Merge branch 'master' of github.com:stefan-niedermann/nextcloud-deck

29 files changed, 1807 insertions, 163 deletions

diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/ImportAccountActivity.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/ImportAccountActivity.java
index 957743919..3ded31bb7 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/ImportAccountActivity.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/ImportAccountActivity.java
@@ -83,6 +83,7 @@ public class ImportAccountActivity extends AppCompatActivity {
                 DeckLog.warn("=============================================================");
                 DeckLog.warn("Nextcloud app is not installed. Cannot choose account");
                 DeckLog.logError(e);
+                binding.addButton.setEnabled(true);
             } catch (AndroidGetAccountsPermissionNotGranted e) {
                 binding.addButton.setEnabled(true);
                 AccountImporter.requestAndroidAccountPermissionsAndPickAccount(this);
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/EditActivity.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/EditActivity.java
index 1af96bca5..fcc9d24e6 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/EditActivity.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/EditActivity.java
@@ -25,6 +25,7 @@ import it.niedermann.nextcloud.deck.DeckLog;
 import it.niedermann.nextcloud.deck.R;
 import it.niedermann.nextcloud.deck.databinding.ActivityEditBinding;
 import it.niedermann.nextcloud.deck.model.Account;
+import it.niedermann.nextcloud.deck.model.full.FullCard;
 import it.niedermann.nextcloud.deck.persistence.sync.SyncManager;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedActivity;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedAlertDialogBuilder;
@@ -171,12 +172,16 @@ public class EditActivity extends BrandedActivity {
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         if (item.getItemId() == R.id.action_card_save) {
-            saveAndFinish();
+            saveAndRun(super::finish);
         }
         return super.onOptionsItemSelected(item);
     }
 
-    private void saveAndFinish() {
+    /**
+     * Tries to save the current {@link FullCard} from the {@link EditCardViewModel} and then runs the given {@link Runnable}
+     * @param runnable
+     */
+    private void saveAndRun(@NonNull Runnable runnable) {
         if (!viewModel.isPendingCreation()) {
             viewModel.setPendingCreation(true);
             final String title = viewModel.getFullCard().getCard().getTitle();
@@ -194,9 +199,9 @@ public class EditActivity extends BrandedActivity {
                         .show();
             } else {
                 if (viewModel.isCreateMode()) {
-                    observeOnce(syncManager.createFullCard(viewModel.getAccount().getId(), viewModel.getBoardId(), viewModel.getFullCard().getCard().getStackId(), viewModel.getFullCard()), EditActivity.this, (card) -> super.finish());
+                    observeOnce(syncManager.createFullCard(viewModel.getAccount().getId(), viewModel.getBoardId(), viewModel.getFullCard().getCard().getStackId(), viewModel.getFullCard()), EditActivity.this, (card) -> runnable.run());
                 } else {
-                    observeOnce(syncManager.updateCard(viewModel.getFullCard()), EditActivity.this, (card) -> super.finish());
+                    observeOnce(syncManager.updateCard(viewModel.getFullCard()), EditActivity.this, (card) -> runnable.run());
                 }
             }
         }
@@ -265,26 +270,15 @@ public class EditActivity extends BrandedActivity {
     }
 
     @Override
-    public boolean onSupportNavigateUp() {
-        finish(); // close this activity as oppose to navigating up
-        return true;
-    }
-
-    @Override
-    public void onBackPressed() {
-        finish();
-    }
-
-    @Override
     public void finish() {
         if (!viewModel.hasChanges() && viewModel.canEdit()) {
             new BrandedAlertDialogBuilder(this)
                     .setTitle(R.string.simple_save)
                     .setMessage(R.string.do_you_want_to_save_your_changes)
-                    .setPositiveButton(R.string.simple_save, (dialog, whichButton) -> saveAndFinish())
+                    .setPositiveButton(R.string.simple_save, (dialog, whichButton) -> saveAndRun(super::finish))
                     .setNegativeButton(R.string.simple_discard, (dialog, whichButton) -> super.finish()).show();
         } else {
-            directFinish();
+            super.finish();
         }
     }
 
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/assignee/CardAssigneeDialog.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/assignee/CardAssigneeDialog.java
index 74c89d830..34d2eb3f3 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/assignee/CardAssigneeDialog.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/assignee/CardAssigneeDialog.java
@@ -19,7 +19,7 @@ import com.bumptech.glide.Glide;
 import java.io.Serializable;
 
 import it.niedermann.nextcloud.deck.R;
-import it.niedermann.nextcloud.deck.databinding.DialogAssigneeBinding;
+import it.niedermann.nextcloud.deck.databinding.DialogPreviewBinding;
 import it.niedermann.nextcloud.deck.model.User;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedDeleteAlertDialogBuilder;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedDialogFragment;
@@ -27,10 +27,11 @@ import it.niedermann.nextcloud.deck.ui.card.EditCardViewModel;
 
 import static it.niedermann.nextcloud.deck.DeckApplication.isDarkTheme;
 
+@Deprecated
 public class CardAssigneeDialog extends BrandedDialogFragment {
 
     private static final String KEY_USER = "user";
-    private DialogAssigneeBinding binding;
+    private DialogPreviewBinding binding;
     private EditCardViewModel viewModel;
 
     @Nullable
@@ -63,7 +64,7 @@ public class CardAssigneeDialog extends BrandedDialogFragment {
     @NonNull
     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
-        binding = DialogAssigneeBinding.inflate(LayoutInflater.from(requireContext()));
+        binding = DialogPreviewBinding.inflate(LayoutInflater.from(requireContext()));
         viewModel = new ViewModelProvider(requireActivity()).get(EditCardViewModel.class);
 
         AlertDialog.Builder dialogBuilder = new BrandedDeleteAlertDialogBuilder(requireContext());
@@ -95,7 +96,7 @@ public class CardAssigneeDialog extends BrandedDialogFragment {
                 .placeholder(circularProgressDrawable)
                 .error(R.drawable.ic_person_grey600_24dp)
                 .into(binding.avatar));
-        binding.displayName.setText(user.getDisplayname());
+        binding.title.setText(user.getDisplayname());
     }
 
     @Override
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentAdapter.java
index ea347417a..d601f6bbd 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentAdapter.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentAdapter.java
@@ -14,6 +14,8 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.core.app.ActivityOptionsCompat;
 import androidx.fragment.app.FragmentManager;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
 import androidx.recyclerview.widget.RecyclerView;
 
 import java.util.ArrayList;
@@ -28,6 +30,7 @@ import it.niedermann.nextcloud.deck.ui.attachments.AttachmentsActivity;
 import it.niedermann.nextcloud.deck.ui.branding.Branded;
 import it.niedermann.nextcloud.deck.util.MimeTypeUtil;
 
+import static androidx.lifecycle.Transformations.distinctUntilChanged;
 import static androidx.recyclerview.widget.RecyclerView.NO_ID;
 import static it.niedermann.nextcloud.deck.util.AttachmentUtil.openAttachmentInBrowser;
 
@@ -37,6 +40,9 @@ public class CardAttachmentAdapter extends RecyclerView.Adapter<AttachmentViewHo
     public static final int VIEW_TYPE_DEFAULT = 2;
     public static final int VIEW_TYPE_IMAGE = 1;
 
+    @NonNull
+    private final MutableLiveData<Boolean> isEmpty = new MutableLiveData<>(true);
+    @NonNull
     private final MenuInflater menuInflater;
     @ColorInt
     private int mainColor;
@@ -45,9 +51,9 @@ public class CardAttachmentAdapter extends RecyclerView.Adapter<AttachmentViewHo
     private Long cardRemoteId = null;
     private final long cardLocalId;
     @NonNull
-    FragmentManager fragmentManager;
+    private final FragmentManager fragmentManager;
     @NonNull
-    private List<Attachment> attachments = new ArrayList<>();
+    private final List<Attachment> attachments = new ArrayList<>();
     @NonNull
     private final AttachmentClickedListener attachmentClickedListener;
 
@@ -126,22 +132,41 @@ public class CardAttachmentAdapter extends RecyclerView.Adapter<AttachmentViewHo
         return attachments.size();
     }
 
+    private void updateIsEmpty() {
+        this.isEmpty.postValue(getItemCount() <= 0);
+    }
+
+    @NonNull
+    public LiveData<Boolean> isEmpty() {
+        return distinctUntilChanged(this.isEmpty);
+    }
+
     public void setAttachments(@NonNull List<Attachment> attachments, @Nullable Long cardRemoteId) {
         this.cardRemoteId = cardRemoteId;
         this.attachments.clear();
         this.attachments.addAll(attachments);
         notifyDataSetChanged();
+        this.updateIsEmpty();
     }
 
     public void addAttachment(Attachment a) {
-        this.attachments.add(a);
+        this.attachments.add(0, a);
         notifyItemInserted(this.attachments.size());
+        this.updateIsEmpty();
     }
 
     public void removeAttachment(Attachment a) {
         final int index = this.attachments.indexOf(a);
         this.attachments.remove(a);
         notifyItemRemoved(index);
+        this.updateIsEmpty();
+    }
+
+    public void replaceAttachment(Attachment toReplace, Attachment with) {
+        final int index = this.attachments.indexOf(toReplace);
+        this.attachments.remove(toReplace);
+        this.attachments.add(index, with);
+        notifyItemChanged(index);
     }
 
     @Override
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsBottomsheetBehaviorCallback.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsBottomsheetBehaviorCallback.java
new file mode 100644
index 000000000..6b60bbffd
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsBottomsheetBehaviorCallback.java
@@ -0,0 +1,91 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments;
+
+import android.content.Context;
+import android.view.View;
+
+import androidx.activity.OnBackPressedCallback;
+import androidx.annotation.ColorInt;
+import androidx.annotation.ColorRes;
+import androidx.annotation.DimenRes;
+import androidx.annotation.NonNull;
+import androidx.annotation.Px;
+import androidx.core.content.ContextCompat;
+
+import com.google.android.material.animation.ArgbEvaluatorCompat;
+import com.google.android.material.bottomnavigation.BottomNavigationView;
+import com.google.android.material.bottomsheet.BottomSheetBehavior;
+import com.google.android.material.floatingactionbutton.FloatingActionButton;
+
+import it.niedermann.android.util.DimensionUtil;
+
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+import static com.google.android.material.bottomsheet.BottomSheetBehavior.STATE_HIDDEN;
+
+public class CardAttachmentsBottomsheetBehaviorCallback extends BottomSheetBehavior.BottomSheetCallback {
+    @NonNull
+    private final OnBackPressedCallback backPressedCallback;
+    @NonNull
+    private final FloatingActionButton fab;
+    @NonNull
+    private final View pickerBackdrop;
+    @NonNull
+    private final BottomNavigationView bottomNavigation;
+    @ColorInt
+    private final int backdropColorExpanded;
+    @ColorInt
+    private final int backdropColorCollapsed;
+    @Px
+    private final int bottomNavigationHeight;
+
+    private float lastOffset = -1;
+
+    public CardAttachmentsBottomsheetBehaviorCallback(@NonNull Context context,
+                                                      @NonNull OnBackPressedCallback backPressedCallback,
+                                                      @NonNull FloatingActionButton fab,
+                                                      @NonNull View pickerBackdrop,
+                                                      @NonNull BottomNavigationView bottomNavigation,
+                                                      @ColorRes int backdropColorExpanded,
+                                                      @ColorRes int backdropColorCollapsed,
+                                                      @DimenRes int bottomNavigationHeight
+    ) {
+        this.backPressedCallback = backPressedCallback;
+        this.fab = fab;
+        this.pickerBackdrop = pickerBackdrop;
+        this.bottomNavigation = bottomNavigation;
+        this.backdropColorExpanded = ContextCompat.getColor(context, backdropColorExpanded);
+        this.backdropColorCollapsed = ContextCompat.getColor(context, backdropColorCollapsed);
+        this.bottomNavigationHeight = DimensionUtil.INSTANCE.dpToPx(context, bottomNavigationHeight);
+    }
+
+    @Override
+    public void onStateChanged(@NonNull View bottomSheet, int newState) {
+        if (newState == STATE_HIDDEN) {
+            backPressedCallback.setEnabled(false);
+            if (pickerBackdrop.getVisibility() != GONE) {
+                pickerBackdrop.setVisibility(GONE);
+            }
+        } else if (pickerBackdrop.getVisibility() != VISIBLE) {
+            pickerBackdrop.setVisibility(VISIBLE);
+        }
+    }
+
+    @Override
+    public void onSlide(@NonNull View bottomSheet, float slideOffset) {
+        if (slideOffset <= 0) {
+            final float bottomSheetPercentageShown = slideOffset * -1;
+            pickerBackdrop.setBackgroundColor(ArgbEvaluatorCompat.getInstance().evaluate(bottomSheetPercentageShown, backdropColorExpanded, backdropColorCollapsed));
+            bottomNavigation.setTranslationY(bottomSheetPercentageShown * bottomNavigationHeight);
+            if (slideOffset <= lastOffset && slideOffset != 0) {
+                if (fab.getVisibility() == GONE) {
+                    fab.show();
+                }
+            } else {
+                if (fab.getVisibility() == VISIBLE) {
+                    fab.hide();
+                }
+            }
+        }
+        lastOffset = slideOffset;
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsFragment.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsFragment.java
index 1c8a84103..bb42f27ef 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsFragment.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/CardAttachmentsFragment.java
@@ -1,23 +1,32 @@
 package it.niedermann.nextcloud.deck.ui.card.attachments;
 
 import android.content.ContentResolver;
+import android.content.Context;
 import android.content.Intent;
+import android.content.res.ColorStateList;
 import android.net.Uri;
 import android.os.Bundle;
+import android.provider.ContactsContract;
 import android.util.DisplayMetrics;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.LinearLayout;
 import android.widget.Toast;
 
+import androidx.activity.OnBackPressedCallback;
+import androidx.annotation.ColorInt;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.core.app.SharedElementCallback;
+import androidx.core.content.ContextCompat;
 import androidx.fragment.app.Fragment;
 import androidx.lifecycle.ViewModelProvider;
 import androidx.recyclerview.widget.GridLayoutManager;
+import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
+import com.google.android.material.bottomsheet.BottomSheetBehavior;
 import com.google.android.material.snackbar.Snackbar;
 import com.nextcloud.android.sso.exceptions.NextcloudHttpRequestFailedException;
 
@@ -27,6 +36,7 @@ import java.time.Instant;
 import java.util.List;
 import java.util.Map;
 
+import it.niedermann.android.util.DimensionUtil;
 import it.niedermann.nextcloud.deck.DeckLog;
 import it.niedermann.nextcloud.deck.R;
 import it.niedermann.nextcloud.deck.databinding.FragmentCardEditTabAttachmentsBinding;
@@ -38,16 +48,36 @@ import it.niedermann.nextcloud.deck.persistence.sync.adapters.db.util.WrappedLiv
 import it.niedermann.nextcloud.deck.ui.branding.BrandedFragment;
 import it.niedermann.nextcloud.deck.ui.branding.BrandedSnackbar;
 import it.niedermann.nextcloud.deck.ui.card.EditCardViewModel;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.AbstractPickerAdapter;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.ContactAdapter;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.FileAdapter;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.FileAdapterLegacy;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.GalleryAdapter;
+import it.niedermann.nextcloud.deck.ui.card.attachments.picker.GalleryItemDecoration;
+import it.niedermann.nextcloud.deck.ui.card.attachments.previewdialog.PreviewDialog;
+import it.niedermann.nextcloud.deck.ui.card.attachments.previewdialog.PreviewDialogViewModel;
 import it.niedermann.nextcloud.deck.ui.exception.ExceptionDialogFragment;
+import it.niedermann.nextcloud.deck.ui.takephoto.TakePhotoActivity;
+import it.niedermann.nextcloud.deck.util.DeckColorUtil;
+import it.niedermann.nextcloud.deck.util.VCardUtil;
 
+import static android.Manifest.permission.CAMERA;
+import static android.Manifest.permission.READ_CONTACTS;
 import static android.Manifest.permission.READ_EXTERNAL_STORAGE;
 import static android.app.Activity.RESULT_OK;
 import static android.os.Build.VERSION.SDK_INT;
+import static android.os.Build.VERSION_CODES.LOLLIPOP;
 import static android.os.Build.VERSION_CODES.M;
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
 import static androidx.core.content.PermissionChecker.PERMISSION_GRANTED;
 import static androidx.core.content.PermissionChecker.checkSelfPermission;
+import static com.google.android.material.bottomsheet.BottomSheetBehavior.STATE_COLLAPSED;
+import static com.google.android.material.bottomsheet.BottomSheetBehavior.STATE_HIDDEN;
 import static it.niedermann.nextcloud.deck.persistence.sync.adapters.db.util.LiveDataHelper.observeOnce;
 import static it.niedermann.nextcloud.deck.ui.branding.BrandingUtil.applyBrandToFAB;
+import static it.niedermann.nextcloud.deck.ui.branding.BrandingUtil.isBrandingEnabled;
+import static it.niedermann.nextcloud.deck.ui.branding.BrandingUtil.readBrandMainColor;
 import static it.niedermann.nextcloud.deck.ui.card.attachments.CardAttachmentAdapter.VIEW_TYPE_DEFAULT;
 import static it.niedermann.nextcloud.deck.ui.card.attachments.CardAttachmentAdapter.VIEW_TYPE_IMAGE;
 import static it.niedermann.nextcloud.deck.util.AttachmentUtil.copyContentUriToTempFile;
@@ -56,14 +86,36 @@ import static java.net.HttpURLConnection.HTTP_CONFLICT;
 public class CardAttachmentsFragment extends BrandedFragment implements AttachmentDeletedListener, AttachmentClickedListener {
 
     private FragmentCardEditTabAttachmentsBinding binding;
-    private EditCardViewModel viewModel;
+    private EditCardViewModel editViewModel;
+    private PreviewDialogViewModel previewViewModel;
+    private BottomSheetBehavior<LinearLayout> mBottomSheetBehaviour;
 
-    private static final int REQUEST_CODE_ADD_FILE = 1;
-    private static final int REQUEST_CODE_ADD_FILE_PERMISSION = 2;
+    private RecyclerView.ItemDecoration galleryItemDecoration;
+
+    private static final int REQUEST_CODE_PICK_FILE = 1;
+    private static final int REQUEST_CODE_PICK_FILE_PERMISSION = 2;
+    private static final int REQUEST_CODE_PICK_CAMERA = 3;
+    private static final int REQUEST_CODE_PICK_GALLERY_PERMISSION = 4;
+    private static final int REQUEST_CODE_PICK_CONTACT = 5;
+    private static final int REQUEST_CODE_PICK_CONTACT_PICKER_PERMISSION = 6;
+
+    @ColorInt
+    private int accentColor;
+    @ColorInt
+    private int primaryColor;
 
     private SyncManager syncManager;
     private CardAttachmentAdapter adapter;
 
+    private AbstractPickerAdapter<?> pickerAdapter;
+
+    private final OnBackPressedCallback backPressedCallback = new OnBackPressedCallback(true) {
+        @Override
+        public void handleOnBackPressed() {
+            mBottomSheetBehaviour.setState(STATE_HIDDEN);
+        }
+    };
+
     private int clickedItemPosition;
 
     @Override
@@ -72,11 +124,24 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
                              Bundle savedInstanceState) {
 
         binding = FragmentCardEditTabAttachmentsBinding.inflate(inflater, container, false);
-        viewModel = new ViewModelProvider(requireActivity()).get(EditCardViewModel.class);
+        editViewModel = new ViewModelProvider(requireActivity()).get(EditCardViewModel.class);
+        previewViewModel = new ViewModelProvider(requireActivity()).get(PreviewDialogViewModel.class);
+        binding.bottomNavigation.setOnNavigationItemSelectedListener(item -> {
+            if (item.getItemId() == R.id.gallery) {
+                showGalleryPicker();
+            } else if (item.getItemId() == R.id.contacts) {
+                showContactPicker();
+            } else if (item.getItemId() == R.id.files) {
+                showFilePicker();
+            }
+            return true;
+        });
+        accentColor = ContextCompat.getColor(requireContext(), R.color.accent);
+        primaryColor = ContextCompat.getColor(requireContext(), R.color.primary);
 
         // This might be a zombie fragment with an empty EditCardViewModel after Android killed the activity (but not the fragment instance
         // See https://github.com/stefan-niedermann/nextcloud-deck/issues/478
-        if (viewModel.getFullCard() == null) {
+        if (editViewModel.getFullCard() == null) {
             DeckLog.logError(new IllegalStateException("Cannot populate " + CardAttachmentsFragment.class.getSimpleName() + " because viewModel.getFullCard() is null"));
             return binding.getRoot();
         }
@@ -86,15 +151,32 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
                 getChildFragmentManager(),
                 requireActivity().getMenuInflater(),
                 this,
-                viewModel.getAccount(),
-                viewModel.getFullCard().getLocalId());
+                editViewModel.getAccount(),
+                editViewModel.getFullCard().getLocalId());
         binding.attachmentsList.setAdapter(adapter);
 
-        updateEmptyContentView();
+        adapter.isEmpty().observe(getViewLifecycleOwner(), (isEmpty) -> {
+            if (isEmpty) {
+                this.binding.emptyContentView.setVisibility(VISIBLE);
+                this.binding.attachmentsList.setVisibility(GONE);
+            } else {
+                this.binding.emptyContentView.setVisibility(GONE);
+                this.binding.attachmentsList.setVisibility(VISIBLE);
+            }
+        });
+        galleryItemDecoration = new GalleryItemDecoration(DimensionUtil.INSTANCE.dpToPx(requireContext(), R.dimen.spacer_1qx));
+        mBottomSheetBehaviour = BottomSheetBehavior.from(binding.bottomSheetParent);
+        mBottomSheetBehaviour.setDraggable(true);
+        mBottomSheetBehaviour.setHideable(true);
+        mBottomSheetBehaviour.setState(STATE_HIDDEN);
+        mBottomSheetBehaviour.addBottomSheetCallback(new CardAttachmentsBottomsheetBehaviorCallback(
+                requireContext(), backPressedCallback, binding.fab, binding.pickerBackdrop, binding.bottomNavigation,
+                R.color.mdtp_transparent_black, android.R.color.transparent, R.dimen.attachments_bottom_navigation_height));
+        binding.pickerBackdrop.setOnClickListener(v -> mBottomSheetBehaviour.setState(STATE_HIDDEN));
 
         final DisplayMetrics displayMetrics = getResources().getDisplayMetrics();
-        int spanCount = (int) ((displayMetrics.widthPixels / displayMetrics.density) / getResources().getInteger(R.integer.max_dp_attachment_column));
-        GridLayoutManager glm = new GridLayoutManager(getContext(), spanCount);
+        final int spanCount = (int) ((displayMetrics.widthPixels / displayMetrics.density) / getResources().getInteger(R.integer.max_dp_attachment_column));
+        final GridLayoutManager glm = new GridLayoutManager(getContext(), spanCount);
         glm.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
             @Override
             public int getSpanSize(int position) {
@@ -108,7 +190,7 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
             }
         });
         binding.attachmentsList.setLayoutManager(glm);
-        if (!viewModel.isCreateMode()) {
+        if (!editViewModel.isCreateMode()) {
             // https://android-developers.googleblog.com/2018/02/continuous-shared-element-transitions.html?m=1
             // https://github.com/android/animation-samples/blob/master/GridToPager/app/src/main/java/com/google/samples/gridtopager/fragment/ImagePagerFragment.java
             setExitSharedElementCallback(new SharedElementCallback() {
@@ -121,12 +203,21 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
                     }
                 }
             });
-            adapter.setAttachments(viewModel.getFullCard().getAttachments(), viewModel.getFullCard().getId());
-            updateEmptyContentView();
+            adapter.setAttachments(editViewModel.getFullCard().getAttachments(), editViewModel.getFullCard().getId());
         }
 
-        if (viewModel.canEdit()) {
-            binding.fab.setOnClickListener(v -> pickFile());
+        if (editViewModel.canEdit()) {
+            binding.fab.setOnClickListener(v -> {
+                if (SDK_INT < LOLLIPOP) {
+                    openNativeFilePicker();
+                } else {
+                    binding.bottomNavigation.setSelectedItemId(R.id.gallery);
+                    showGalleryPicker();
+                    mBottomSheetBehaviour.setState(STATE_COLLAPSED);
+                    backPressedCallback.setEnabled(true);
+                    requireActivity().getOnBackPressedDispatcher().addCallback(getViewLifecycleOwner(), backPressedCallback);
+                }
+            });
             binding.fab.show();
             binding.attachmentsList.addOnScrollListener(new RecyclerView.OnScrollListener() {
                 @Override
@@ -141,113 +232,264 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
             binding.fab.hide();
             binding.emptyContentView.hideDescription();
         }
+        @Nullable Context context = requireContext();
+        if (isBrandingEnabled(context)) {
+            applyBrand(readBrandMainColor(context));
+        }
         return binding.getRoot();
     }
 
-    public void pickFile() {
-        if (SDK_INT >= M && checkSelfPermission(requireActivity(), READ_EXTERNAL_STORAGE) != PERMISSION_GRANTED) {
-            requestPermissions(new String[]{READ_EXTERNAL_STORAGE}, REQUEST_CODE_ADD_FILE_PERMISSION);
+    @Override
+    public void onPause() {
+        super.onPause();
+        backPressedCallback.setEnabled(false);
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        backPressedCallback.setEnabled(binding.bottomNavigation.getTranslationY() == 0);
+    }
+
+    private void showGalleryPicker() {
+        if (!(pickerAdapter instanceof GalleryAdapter)) {
+            if (isPermissionRequestNeeded(READ_EXTERNAL_STORAGE) || isPermissionRequestNeeded(CAMERA)) {
+                requestPermissions(new String[]{READ_EXTERNAL_STORAGE, CAMERA}, REQUEST_CODE_PICK_GALLERY_PERMISSION);
+            } else {
+                unbindPickerAdapter();
+                pickerAdapter = new GalleryAdapter(requireContext(), (uri, pair) -> {
+                    previewViewModel.prepareDialog(pair.first, pair.second);
+                    PreviewDialog.newInstance().show(getChildFragmentManager(), PreviewDialog.class.getSimpleName());
+                    observeOnce(previewViewModel.getResult(), getViewLifecycleOwner(), (submitPositive) -> {
+                        if (submitPositive) {
+                            onActivityResult(REQUEST_CODE_PICK_FILE, RESULT_OK, new Intent().setData(uri));
+                        }
+                    });
+                }, this::openNativeCameraPicker, getViewLifecycleOwner());
+                if (binding.pickerRecyclerView.getItemDecorationCount() == 0) {
+                    binding.pickerRecyclerView.addItemDecoration(galleryItemDecoration);
+                }
+                binding.pickerRecyclerView.setLayoutManager(new GridLayoutManager(requireContext(), 3));
+                binding.pickerRecyclerView.setAdapter(pickerAdapter);
+            }
+        }
+    }
+
+    private void showContactPicker() {
+        if (!(pickerAdapter instanceof ContactAdapter)) {
+            if (isPermissionRequestNeeded(READ_CONTACTS)) {
+                requestPermissions(new String[]{READ_CONTACTS}, REQUEST_CODE_PICK_CONTACT_PICKER_PERMISSION);
+            } else {
+                unbindPickerAdapter();
+                pickerAdapter = new ContactAdapter(requireContext(), (uri, pair) -> {
+                    previewViewModel.prepareDialog(pair.first, pair.second);
+                    PreviewDialog.newInstance().show(getChildFragmentManager(), PreviewDialog.class.getSimpleName());
+                    observeOnce(previewViewModel.getResult(), getViewLifecycleOwner(), (submitPositive) -> {
+                        if (submitPositive) {
+                            onActivityResult(REQUEST_CODE_PICK_CONTACT, RESULT_OK, new Intent().setData(uri));
+                        }
+                    });
+                }, this::openNativeContactPicker);
+                removeGalleryItemDecoration();
+                binding.pickerRecyclerView.setLayoutManager(new LinearLayoutManager(requireContext()));
+                binding.pickerRecyclerView.setAdapter(pickerAdapter);
+            }
+        }
+    }
+
+    private void showFilePicker() {
+        if (!(pickerAdapter instanceof FileAdapter) && !(pickerAdapter instanceof FileAdapterLegacy)) {
+            if (isPermissionRequestNeeded(READ_EXTERNAL_STORAGE)) {
+                requestPermissions(new String[]{READ_EXTERNAL_STORAGE}, REQUEST_CODE_PICK_FILE_PERMISSION);
+            } else {
+                unbindPickerAdapter();
+                if (SDK_INT >= LOLLIPOP) {
+//                    if (SDK_INT >= Build.VERSION_CODES.Q) {
+//                        // TODO Only usable with Scoped Storage
+//                        pickerAdapter = new FileAdapter(requireContext(), uri -> onActivityResult(REQUEST_CODE_PICK_FILE, RESULT_OK, new Intent().setData(uri)), this::openNativeFilePicker);
+//                    } else {
+                    pickerAdapter = new FileAdapterLegacy((uri, pair) -> {
+                        previewViewModel.prepareDialog(pair.first, pair.second);
+                        PreviewDialog.newInstance().show(getChildFragmentManager(), PreviewDialog.class.getSimpleName());
+                        observeOnce(previewViewModel.getResult(), getViewLifecycleOwner(), (submitPositive) -> {
+                            if (submitPositive) {
+                                onActivityResult(REQUEST_CODE_PICK_FILE, RESULT_OK, new Intent().setData(uri));
+                            }
+                        });
+                    }, this::openNativeFilePicker);
+//                    }
+                    removeGalleryItemDecoration();
+                    binding.pickerRecyclerView.setLayoutManager(new LinearLayoutManager(requireContext()));
+                    binding.pickerRecyclerView.setAdapter(pickerAdapter);
+                }
+            }
+        }
+    }
+
+    private void openNativeCameraPicker() {
+        if (SDK_INT >= LOLLIPOP) {
+            startActivityForResult(TakePhotoActivity.createIntent(requireContext()), REQUEST_CODE_PICK_CAMERA);
         } else {
-            startActivityForResult(new Intent(Intent.ACTION_GET_CONTENT)
-                    .addCategory(Intent.CATEGORY_OPENABLE)
-                    .setType("*/*"), REQUEST_CODE_ADD_FILE);
+            ExceptionDialogFragment.newInstance(new UnsupportedOperationException("This feature requires Android 5"), editViewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
+        }
+    }
+
+    private void openNativeContactPicker() {
+        final Intent intent = new Intent(Intent.ACTION_PICK).setType(ContactsContract.Contacts.CONTENT_TYPE);
+        if (intent.resolveActivity(requireContext().getPackageManager()) != null) {
+            startActivityForResult(intent, REQUEST_CODE_PICK_CONTACT);
+        }
+    }
+
+    private void openNativeFilePicker() {
+        startActivityForResult(new Intent(Intent.ACTION_GET_CONTENT)
+                .addCategory(Intent.CATEGORY_OPENABLE)
+                .setType("*/*"), REQUEST_CODE_PICK_FILE);
+    }
+
+    /**
+     * Checks the current Android version and whether the permission has already been granted.
+     *
+     * @param permission see {@link android.Manifest.permission}
+     * @return whether or not requesting permission is needed
+     */
+    private boolean isPermissionRequestNeeded(@NonNull String permission) {
+        return SDK_INT >= M && checkSelfPermission(requireActivity(), permission) != PERMISSION_GRANTED;
+    }
+
+    private void unbindPickerAdapter() {
+        if (pickerAdapter != null) {
+            pickerAdapter.onDestroy();
+        }
+    }
+
+    private void removeGalleryItemDecoration() {
+        if (binding.pickerRecyclerView.getItemDecorationCount() > 0) {
+            binding.pickerRecyclerView.removeItemDecoration(galleryItemDecoration);
         }
     }
 
     @Override
     public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
-        //noinspection SwitchStatementWithTooFewBranches
+        super.onActivityResult(requestCode, resultCode, data);
         switch (requestCode) {
-            case REQUEST_CODE_ADD_FILE: {
+            case REQUEST_CODE_PICK_CONTACT:
+            case REQUEST_CODE_PICK_CAMERA:
+            case REQUEST_CODE_PICK_FILE: {
                 if (resultCode == RESULT_OK) {
-                    if (data == null) {
-                        ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("Intent data is null"), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
-                        return;
-                    }
-                    final Uri sourceUri = data.getData();
-                    if (sourceUri == null) {
-                        ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("sourceUri is null"), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
-                        return;
-                    }
-                    if (!ContentResolver.SCHEME_CONTENT.equals(sourceUri.getScheme())) {
-                        ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("Unknown URI scheme: " + sourceUri.getScheme()), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
-                        return;
+                    final Uri sourceUri = requestCode == REQUEST_CODE_PICK_CONTACT
+                            ? VCardUtil.getVCardContentUri(requireContext(), Uri.parse(data.getDataString()))
+                            : data.getData();
+                    try {
+                        uploadNewAttachmentFromUri(sourceUri, requestCode == REQUEST_CODE_PICK_CAMERA
+                                ? data.getType()
+                                : requireContext().getContentResolver().getType(sourceUri));
+                        mBottomSheetBehaviour.setState(STATE_HIDDEN);
+                    } catch (Exception e) {
+                        ExceptionDialogFragment.newInstance(e, editViewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
                     }
+                }
+                break;
+            }
+            default: {
+                super.onActivityResult(requestCode, resultCode, data);
+            }
+        }
+    }
 
-                    DeckLog.verbose("--- found content URL " + sourceUri.getPath());
-                    File fileToUpload;
+    @Override
+    public void onDestroy() {
+        if (this.pickerAdapter != null) {
+            this.pickerAdapter.onDestroy();
+            this.binding.pickerRecyclerView.setAdapter(null);
+        }
+        super.onDestroy();
+    }
 
-                    try {
-                        DeckLog.verbose("---- so, now copy & upload: " + sourceUri.getPath());
-                        fileToUpload = copyContentUriToTempFile(requireContext(), sourceUri, viewModel.getAccount().getId(), viewModel.getFullCard().getCard().getLocalId());
-                    } catch (IllegalArgumentException | IOException e) {
-                        ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("Could not copy content URI to temporary file", e), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
+    private void uploadNewAttachmentFromUri(@NonNull Uri sourceUri, String mimeType) throws UploadAttachmentFailedException, IOException {
+        if (sourceUri == null) {
+            throw new UploadAttachmentFailedException("sourceUri is null");
+        }
+        switch (sourceUri.getScheme()) {
+            case ContentResolver.SCHEME_CONTENT:
+            case ContentResolver.SCHEME_FILE: {
+                DeckLog.verbose("--- found content URL " + sourceUri.getPath());
+                final File fileToUpload = copyContentUriToTempFile(requireContext(), sourceUri, editViewModel.getAccount().getId(), editViewModel.getFullCard().getLocalId());
+                for (Attachment existingAttachment : editViewModel.getFullCard().getAttachments()) {
+                    final String existingPath = existingAttachment.getLocalPath();
+                    if (existingPath != null && existingPath.equals(fileToUpload.getAbsolutePath())) {
+                        BrandedSnackbar.make(binding.coordinatorLayout, R.string.attachment_already_exists, Snackbar.LENGTH_LONG).show();
                         return;
                     }
-
-                    for (Attachment existingAttachment : viewModel.getFullCard().getAttachments()) {
-                        final String existingPath = existingAttachment.getLocalPath();
-                        if (existingPath != null && existingPath.equals(fileToUpload.getAbsolutePath())) {
-                            BrandedSnackbar.make(binding.coordinatorLayout, R.string.attachment_already_exists, Snackbar.LENGTH_LONG).show();
-                            return;
-                        }
-                    }
-
-                    final Instant now = Instant.now();
-                    final Attachment a = new Attachment();
-                    a.setMimetype(requireContext().getContentResolver().getType(sourceUri));
-                    a.setData(fileToUpload.getName());
-                    a.setFilename(fileToUpload.getName());
-                    a.setBasename(fileToUpload.getName());
-                    a.setFilesize(fileToUpload.length());
-                    a.setLocalPath(fileToUpload.getAbsolutePath());
-                    a.setLastModifiedLocal(now);
-                    a.setStatusEnum(DBStatus.LOCAL_EDITED);
-                    a.setCreatedAt(now);
-                    viewModel.getFullCard().getAttachments().add(a);
-                    adapter.addAttachment(a);
-                    if (!viewModel.isCreateMode()) {
-                        WrappedLiveData<Attachment> liveData = syncManager.addAttachmentToCard(viewModel.getAccount().getId(), viewModel.getFullCard().getLocalId(), a.getMimetype(), fileToUpload);
-                        observeOnce(liveData, getViewLifecycleOwner(), (next) -> {
-                            if (liveData.hasError()) {
-                                Throwable t = liveData.getError();
-                                if (t instanceof NextcloudHttpRequestFailedException && ((NextcloudHttpRequestFailedException) t).getStatusCode() == HTTP_CONFLICT) {
-                                    // https://github.com/stefan-niedermann/nextcloud-deck/issues/534
-                                    viewModel.getFullCard().getAttachments().remove(a);
-                                    adapter.removeAttachment(a);
-                                    BrandedSnackbar.make(binding.coordinatorLayout, R.string.attachment_already_exists, Snackbar.LENGTH_LONG).show();
-                                } else {
-                                    ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("Unknown URI scheme", t), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
-                                }
-                            } else {
-                                viewModel.getFullCard().getAttachments().remove(a);
+                }
+                final Instant now = Instant.now();
+                final Attachment a = new Attachment();
+                a.setMimetype(mimeType);
+                a.setData(fileToUpload.getName());
+                a.setFilename(fileToUpload.getName());
+                a.setBasename(fileToUpload.getName());
+                a.setFilesize(fileToUpload.length());
+                a.setLocalPath(fileToUpload.getAbsolutePath());
+                a.setLastModifiedLocal(now);
+                a.setCreatedAt(now);
+                a.setStatusEnum(DBStatus.LOCAL_EDITED);
+                editViewModel.getFullCard().getAttachments().add(0, a);
+                adapter.addAttachment(a);
+                if (!editViewModel.isCreateMode()) {
+                    WrappedLiveData<Attachment> liveData = syncManager.addAttachmentToCard(editViewModel.getAccount().getId(), editViewModel.getFullCard().getLocalId(), a.getMimetype(), fileToUpload);
+                    observeOnce(liveData, getViewLifecycleOwner(), (next) -> {
+                        if (liveData.hasError()) {
+                            Throwable t = liveData.getError();
+                            if (t instanceof NextcloudHttpRequestFailedException && ((NextcloudHttpRequestFailedException) t).getStatusCode() == HTTP_CONFLICT) {
+                                // https://github.com/stefan-niedermann/nextcloud-deck/issues/534
+                                editViewModel.getFullCard().getAttachments().remove(a);
                                 adapter.removeAttachment(a);
-                                viewModel.getFullCard().getAttachments().add(next);
-                                adapter.addAttachment(next);
+                                BrandedSnackbar.make(binding.coordinatorLayout, R.string.attachment_already_exists, Snackbar.LENGTH_LONG).show();
+                            } else {
+                                ExceptionDialogFragment.newInstance(new UploadAttachmentFailedException("Unknown URI scheme", t), editViewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
                             }
-                        });
-                    }
-                    updateEmptyContentView();
+                        } else {
+                            editViewModel.getFullCard().getAttachments().remove(a);
+                            editViewModel.getFullCard().getAttachments().add(0, next);
+                            adapter.replaceAttachment(a, next);
+                        }
+                    });
                 }
                 break;
             }
             default: {
-                super.onActivityResult(requestCode, resultCode, data);
+                throw new UploadAttachmentFailedException("Unknown URI scheme: " + sourceUri.getScheme());
             }
         }
     }
 
     @Override
     public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
-        //noinspection SwitchStatementWithTooFewBranches
         switch (requestCode) {
-            case REQUEST_CODE_ADD_FILE_PERMISSION:
+            case REQUEST_CODE_PICK_FILE_PERMISSION: {
                 if (checkSelfPermission(requireActivity(), READ_EXTERNAL_STORAGE) == PERMISSION_GRANTED) {
-                    pickFile();
+                    showFilePicker();
+                } else {
+                    Toast.makeText(requireContext(), R.string.cannot_upload_files_without_permission, Toast.LENGTH_LONG).show();
+                }
+                break;
+            }
+            case REQUEST_CODE_PICK_GALLERY_PERMISSION: {
+                if (checkSelfPermission(requireActivity(), READ_EXTERNAL_STORAGE) == PERMISSION_GRANTED && checkSelfPermission(requireActivity(), CAMERA) == PERMISSION_GRANTED) {
+                    showGalleryPicker();
+                } else {
+                    Toast.makeText(requireContext(), R.string.cannot_upload_files_without_permission, Toast.LENGTH_LONG).show();
+                }
+                break;
+            }
+            case REQUEST_CODE_PICK_CONTACT_PICKER_PERMISSION: {
+                if (checkSelfPermission(requireActivity(), READ_CONTACTS) == PERMISSION_GRANTED) {
+                    showContactPicker();
                 } else {
                     Toast.makeText(requireContext(), R.string.cannot_upload_files_without_permission, Toast.LENGTH_LONG).show();
                 }
                 break;
+            }
             default:
                 super.onRequestPermissionsResult(requestCode, permissions, grantResults);
         }
@@ -256,16 +498,15 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
     @Override
     public void onAttachmentDeleted(Attachment attachment) {
         adapter.removeAttachment(attachment);
-        viewModel.getFullCard().getAttachments().remove(attachment);
-        if (!viewModel.isCreateMode() && attachment.getLocalId() != null) {
-            final WrappedLiveData<Void> deleteLiveData = syncManager.deleteAttachmentOfCard(viewModel.getAccount().getId(), viewModel.getFullCard().getLocalId(), attachment.getLocalId());
+        editViewModel.getFullCard().getAttachments().remove(attachment);
+        if (!editViewModel.isCreateMode() && attachment.getLocalId() != null) {
+            final WrappedLiveData<Void> deleteLiveData = syncManager.deleteAttachmentOfCard(editViewModel.getAccount().getId(), editViewModel.getFullCard().getLocalId(), attachment.getLocalId());
             observeOnce(deleteLiveData, this, (next) -> {
                 if (deleteLiveData.hasError() && !SyncManager.ignoreExceptionOnVoidError(deleteLiveData.getError())) {
-                    ExceptionDialogFragment.newInstance(deleteLiveData.getError(), viewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
+                    ExceptionDialogFragment.newInstance(deleteLiveData.getError(), editViewModel.getAccount()).show(getChildFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
                 }
             });
         }
-        updateEmptyContentView();
     }
 
     @Override
@@ -273,20 +514,25 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
         this.clickedItemPosition = position;
     }
 
-    private void updateEmptyContentView() {
-        if (this.adapter == null || this.adapter.getItemCount() == 0) {
-            this.binding.emptyContentView.setVisibility(View.VISIBLE);
-            this.binding.attachmentsList.setVisibility(View.GONE);
-        } else {
-            this.binding.emptyContentView.setVisibility(View.GONE);
-            this.binding.attachmentsList.setVisibility(View.VISIBLE);
-        }
-    }
-
     @Override
     public void applyBrand(int mainColor) {
         applyBrandToFAB(mainColor, binding.fab);
         adapter.applyBrand(mainColor);
+        @ColorInt final int finalMainColor = DeckColorUtil.contrastRatioIsSufficient(mainColor, primaryColor)
+                ? mainColor
+                : accentColor;
+        final ColorStateList list = new ColorStateList(
+                new int[][]{
+                        new int[]{android.R.attr.state_checked},
+                        new int[]{}
+                },
+                new int[]{
+                        finalMainColor,
+                        accentColor
+                }
+        );
+        binding.bottomNavigation.setItemIconTintList(list);
+        binding.bottomNavigation.setItemTextColor(list);
     }
 
     public static Fragment newInstance() {
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/DefaultAttachmentViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/DefaultAttachmentViewHolder.java
index 3f7287c24..2b5358eb9 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/DefaultAttachmentViewHolder.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/DefaultAttachmentViewHolder.java
@@ -10,16 +10,16 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.fragment.app.FragmentManager;
 
-import it.niedermann.nextcloud.deck.R;
 import it.niedermann.nextcloud.deck.databinding.ItemAttachmentDefaultBinding;
 import it.niedermann.nextcloud.deck.model.Account;
 import it.niedermann.nextcloud.deck.model.Attachment;
-import it.niedermann.nextcloud.deck.util.AttachmentUtil;
 import it.niedermann.nextcloud.deck.util.DateUtil;
-import it.niedermann.nextcloud.deck.util.MimeTypeUtil;
+
+import static it.niedermann.nextcloud.deck.util.AttachmentUtil.getIconForMimeType;
+import static it.niedermann.nextcloud.deck.util.AttachmentUtil.openAttachmentInBrowser;
 
 public class DefaultAttachmentViewHolder extends AttachmentViewHolder {
-    private ItemAttachmentDefaultBinding binding;
+    private final ItemAttachmentDefaultBinding binding;
 
     @SuppressWarnings("WeakerAccess")
     public DefaultAttachmentViewHolder(ItemAttachmentDefaultBinding binding) {
@@ -39,20 +39,8 @@ public class DefaultAttachmentViewHolder extends AttachmentViewHolder {
 
     public void bind(@NonNull Account account, @NonNull MenuInflater menuInflater, @NonNull FragmentManager fragmentManager, Long cardRemoteId, Attachment attachment, @Nullable View.OnClickListener onClickListener, @ColorInt int mainColor) {
         super.bind(account, menuInflater, fragmentManager, cardRemoteId, attachment, onClickListener, mainColor);
-
-        if (MimeTypeUtil.isAudio(attachment.getMimetype())) {
-            getPreview().setImageResource(R.drawable.ic_music_note_grey600_24dp);
-        } else if (MimeTypeUtil.isVideo(attachment.getMimetype())) {
-            getPreview().setImageResource(R.drawable.ic_local_movies_grey600_24dp);
-        } else if (MimeTypeUtil.isPdf(attachment.getMimetype())) {
-            getPreview().setImageResource(R.drawable.ic_baseline_picture_as_pdf_24);
-        } else if (MimeTypeUtil.isContact(attachment.getMimetype())) {
-            getPreview().setImageResource(R.drawable.ic_baseline_contact_mail_24);
-        } else {
-            getPreview().setImageResource(R.drawable.ic_attach_file_grey600_24dp);
-        }
-
-        itemView.setOnClickListener((event) -> AttachmentUtil.openAttachmentInBrowser(itemView.getContext(), account.getUrl(), cardRemoteId, attachment.getId()));
+        getPreview().setImageResource(getIconForMimeType(attachment.getMimetype()));
+        itemView.setOnClickListener((event) -> openAttachmentInBrowser(itemView.getContext(), account.getUrl(), cardRemoteId, attachment.getId()));
         binding.filename.setText(attachment.getBasename());
         binding.filesize.setText(Formatter.formatFileSize(binding.filesize.getContext(), attachment.getFilesize()));
         if (attachment.getLastModifiedLocal() != null) {
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractCursorPickerAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractCursorPickerAdapter.java
new file mode 100644
index 000000000..a2ea6dd37
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractCursorPickerAdapter.java
@@ -0,0 +1,100 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.Cursor;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.util.Pair;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.function.BiConsumer;
+
+import static android.database.Cursor.FIELD_TYPE_INTEGER;
+import static android.database.Cursor.FIELD_TYPE_NULL;
+import static androidx.recyclerview.widget.RecyclerView.NO_ID;
+import static java.util.Objects.requireNonNull;
+
+/**
+ * An {@link RecyclerView.Adapter} which provides previews of one type of files and also an option to open a native dialog.
+ * <p>
+ * Example: Previews for images of the gallery as well a one option to take a photo
+ */
+public abstract class AbstractCursorPickerAdapter<T extends RecyclerView.ViewHolder> extends AbstractPickerAdapter<T> {
+
+    private final int count;
+    protected final int columnIndex;
+    private final int columnIndexType;
+    @NonNull
+    protected final BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect;
+    @NonNull
+    protected final Runnable openNativePicker;
+    @NonNull
+    protected final Cursor cursor;
+    @NonNull
+    protected final ContentResolver contentResolver;
+
+    /**
+     * Should be used to bind heavy operations like when dealing with {@link Bitmap}.
+     * This must only be one {@link Thread} because otherwise the cursor might change while fetching data from it.
+     */
+    @NonNull
+    protected final ExecutorService bindExecutor = Executors.newFixedThreadPool(1);
+
+    public AbstractCursorPickerAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable openNativePicker, Uri subject, String idColumn, String sortOrder) {
+        this(context, onSelect, openNativePicker, subject, idColumn, new String[]{idColumn}, sortOrder);
+    }
+
+    public AbstractCursorPickerAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable openNativePicker, Uri subject, String idColumn, String[] requestedColumns, String sortOrder) {
+        this(context, onSelect, openNativePicker, idColumn, requireNonNull(context.getContentResolver().query(subject, requestedColumns, null, null, sortOrder)));
+    }
+
+    public AbstractCursorPickerAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable openNativePicker, String idColumn, @NonNull Cursor cursor) {
+        this.contentResolver = context.getContentResolver();
+        this.onSelect = onSelect;
+        this.openNativePicker = openNativePicker;
+        this.cursor = cursor;
+        this.cursor.moveToFirst();
+        this.columnIndex = this.cursor.getColumnIndex(idColumn);
+        this.count = cursor.getCount() + 1;
+        this.columnIndexType = (this.count > 1) ? this.cursor.getType(columnIndex) : FIELD_TYPE_NULL;
+        setHasStableIds(true);
+    }
+
+    /**
+     * Moves the {@link #cursor} to the given position
+     */
+    @Override
+    public long getItemId(int position) {
+        if (!cursor.isClosed() && cursor.moveToPosition(position - 1)) {
+            //noinspection SwitchStatementWithTooFewBranches
+            switch (columnIndexType) {
+                case FIELD_TYPE_INTEGER:
+                    return cursor.getLong(columnIndex);
+                default:
+                    throw new IllegalStateException("Unknown type for columnIndex \"" + columnIndex + "\": " + columnIndexType);
+            }
+        } else {
+            return NO_ID;
+        }
+    }
+
+    @Override
+    public int getItemCount() {
+        return count;
+    }
+
+    /**
+     * Call this method when the {@link AbstractCursorPickerAdapter} is no longer need to free resources.
+     */
+    public void onDestroy() {
+        cursor.close();
+        bindExecutor.shutdownNow();
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractPickerAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractPickerAdapter.java
new file mode 100644
index 000000000..901d204cd
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/AbstractPickerAdapter.java
@@ -0,0 +1,26 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import androidx.recyclerview.widget.RecyclerView;
+
+public abstract class AbstractPickerAdapter<T extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<T> {
+
+    protected static final int VIEW_TYPE_NONE = -1;
+    protected static final int VIEW_TYPE_ITEM = 0;
+    protected static final int VIEW_TYPE_ITEM_NATIVE = 1;
+
+    @Override
+    public int getItemViewType(int position) {
+        if (position > 0) {
+            return VIEW_TYPE_ITEM;
+        } else if (position == 0) {
+            return VIEW_TYPE_ITEM_NATIVE;
+        } else {
+            return VIEW_TYPE_NONE;
+        }
+    }
+
+    /**
+     * Call this method when the {@link AbstractPickerAdapter} is no longer need to free resources.
+     */
+    public abstract void onDestroy();
+}
\ No newline at end of file
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactAdapter.java
new file mode 100644
index 000000000..22ac0c694
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactAdapter.java
@@ -0,0 +1,104 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.ContactsContract;
+import android.text.TextUtils;
+import android.util.Pair;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.databinding.ItemPickerNativeBinding;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerUserBinding;
+
+import static android.provider.ContactsContract.CommonDataKinds.Email.DATA;
+import static android.provider.ContactsContract.CommonDataKinds.Phone.LOOKUP_KEY;
+import static android.provider.ContactsContract.CommonDataKinds.Phone.NUMBER;
+import static android.provider.ContactsContract.Contacts.CONTENT_LOOKUP_URI;
+import static android.provider.ContactsContract.Contacts.CONTENT_URI;
+import static android.provider.ContactsContract.Contacts.DISPLAY_NAME;
+import static android.provider.ContactsContract.Contacts.SORT_KEY_PRIMARY;
+import static android.provider.ContactsContract.Contacts._ID;
+
+public class ContactAdapter extends AbstractCursorPickerAdapter<RecyclerView.ViewHolder> {
+
+    private final int lookupKeyColumnIndex;
+    private final int displayNameColumnIndex;
+
+    public ContactAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable onSelectPicker) {
+        super(context, onSelect, onSelectPicker, CONTENT_URI, _ID, new String[]{_ID, LOOKUP_KEY, DISPLAY_NAME}, SORT_KEY_PRIMARY);
+        lookupKeyColumnIndex = cursor.getColumnIndex(LOOKUP_KEY);
+        displayNameColumnIndex = cursor.getColumnIndex(DISPLAY_NAME);
+        notifyItemRangeInserted(0, getItemCount() + 1);
+    }
+
+    @NonNull
+    @Override
+    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        switch (viewType) {
+            case VIEW_TYPE_ITEM_NATIVE:
+                return new ContactNativeItemViewHolder(ItemPickerNativeBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            case VIEW_TYPE_ITEM:
+                return new ContactItemViewHolder(ItemPickerUserBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            default:
+                throw new IllegalStateException("Unknown viewType " + viewType);
+        }
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
+        switch (getItemViewType(position)) {
+            case VIEW_TYPE_ITEM_NATIVE: {
+                ((ContactNativeItemViewHolder) holder).bind(openNativePicker);
+                break;
+            }
+            case VIEW_TYPE_ITEM: {
+                final ContactItemViewHolder viewHolder = (ContactItemViewHolder) holder;
+                if (!cursor.isClosed()) {
+                    cursor.moveToPosition(position - 1);
+                    final String displayName = cursor.getString(displayNameColumnIndex);
+                    final String lookupKey = cursor.getString(lookupKeyColumnIndex);
+                    bindExecutor.execute(() -> {
+                        try (InputStream inputStream = ContactsContract.Contacts.openContactPhotoInputStream(contentResolver, Uri.withAppendedPath(CONTENT_LOOKUP_URI, lookupKey))) {
+                            final Bitmap thumbnail = BitmapFactory.decodeStream(inputStream);
+                            String contactInformation = "";
+                            try (final Cursor phoneCursor = contentResolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, new String[]{NUMBER}, LOOKUP_KEY + " = ?", new String[]{lookupKey}, null)) {
+                                if (phoneCursor != null && phoneCursor.moveToFirst()) {
+                                    contactInformation = phoneCursor.getString(phoneCursor.getColumnIndex(NUMBER));
+                                }
+                            }
+                            if (TextUtils.isEmpty(contactInformation)) {
+                                try (final Cursor emailCursor = contentResolver.query(ContactsContract.CommonDataKinds.Email.CONTENT_URI, new String[]{DATA}, LOOKUP_KEY + " = ?", new String[]{lookupKey}, null)) {
+                                    if (emailCursor != null && emailCursor.moveToFirst()) {
+                                        contactInformation = emailCursor.getString(emailCursor.getColumnIndex(DATA));
+                                    }
+                                }
+                            }
+                            final String finalContactInformation = contactInformation;
+                            new Handler(Looper.getMainLooper()).post(() -> viewHolder.bind(Uri.withAppendedPath(CONTENT_LOOKUP_URI, lookupKey), thumbnail, displayName, finalContactInformation, onSelect));
+                        } catch (IOException ignored) {
+                            new Handler(Looper.getMainLooper()).post(viewHolder::bindError);
+                        }
+                    });
+                } else {
+                    new Handler(Looper.getMainLooper()).post(viewHolder::bindError);
+                }
+                break;
+            }
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactItemViewHolder.java
new file mode 100644
index 000000000..f403fed21
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactItemViewHolder.java
@@ -0,0 +1,66 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.graphics.Bitmap;
+import android.graphics.drawable.ColorDrawable;
+import android.net.Uri;
+import android.text.TextUtils;
+import android.util.Pair;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.Glide;
+import com.bumptech.glide.RequestBuilder;
+import com.bumptech.glide.request.RequestOptions;
+
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerUserBinding;
+
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+import static it.niedermann.nextcloud.deck.util.VCardUtil.getColorBasedOnDisplayName;
+
+public class ContactItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemPickerUserBinding binding;
+
+    public ContactItemViewHolder(@NonNull ItemPickerUserBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(@NonNull Uri uri, @Nullable Bitmap image, @NonNull String displayName, @Nullable String contactInformation, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect) {
+        itemView.setOnClickListener((v) -> onSelect.accept(uri, new Pair<>(displayName, image == null ? null : Glide.with(itemView.getContext()).load(image))));
+        binding.title.setText(displayName);
+        binding.contactInformation.setText(contactInformation);
+        if (image == null) {
+            binding.initials.setVisibility(VISIBLE);
+            binding.initials.setText(TextUtils.isEmpty(displayName)
+                    ? null
+                    : String.valueOf(displayName.charAt(0))
+            );
+            Glide.with(itemView.getContext())
+                    .load(new ColorDrawable(getColorBasedOnDisplayName(itemView.getContext(), displayName)))
+                    .apply(RequestOptions.circleCropTransform())
+                    .into(binding.avatar);
+        } else {
+            binding.initials.setVisibility(GONE);
+            binding.initials.setText(null);
+            Glide.with(itemView.getContext())
+                    .load(image)
+                    .placeholder(R.drawable.ic_person_grey600_24dp)
+                    .apply(RequestOptions.circleCropTransform())
+                    .into(binding.avatar);
+        }
+    }
+
+    public void bindError() {
+        itemView.setOnClickListener(null);
+        Glide.with(itemView.getContext())
+                .load(R.drawable.ic_person_grey600_24dp)
+                .into(binding.avatar);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactNativeItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactNativeItemViewHolder.java
new file mode 100644
index 000000000..a1d7d5921
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/ContactNativeItemViewHolder.java
@@ -0,0 +1,23 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerNativeBinding;
+
+public class ContactNativeItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemPickerNativeBinding binding;
+
+    public ContactNativeItemViewHolder(@NonNull ItemPickerNativeBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(@NonNull Runnable onOpenMajorPicker) {
+        binding.title.setText(R.string.show_all_contacts);
+        binding.subtitle.setText(R.string.contacts);
+        itemView.setOnClickListener((v) -> onOpenMajorPicker.run());
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapter.java
new file mode 100644
index 000000000..aa96a0e69
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapter.java
@@ -0,0 +1,85 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.content.ContentUris;
+import android.content.Context;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.MediaStore;
+import android.util.Pair;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.RequiresApi;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.databinding.ItemAttachmentDefaultBinding;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerNativeBinding;
+
+import static android.provider.MediaStore.Downloads.DATE_ADDED;
+import static android.provider.MediaStore.Downloads.DATE_MODIFIED;
+import static android.provider.MediaStore.Downloads.EXTERNAL_CONTENT_URI;
+import static android.provider.MediaStore.Downloads.MIME_TYPE;
+import static android.provider.MediaStore.Downloads.SIZE;
+import static android.provider.MediaStore.Downloads.TITLE;
+import static android.provider.MediaStore.Downloads._ID;
+import static java.util.Objects.requireNonNull;
+
+@RequiresApi(api = 29)
+public class FileAdapter extends AbstractCursorPickerAdapter<RecyclerView.ViewHolder> {
+
+    private final int displayNameColumnIndex;
+    private final int sizeColumnIndex;
+    private final int modifiedColumnIndex;
+    private final int mimeTypeColumnIndex;
+
+    private FileAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable onSelectPicker) {
+        super(context, onSelect, onSelectPicker, _ID, requireNonNull(context.getContentResolver().query(EXTERNAL_CONTENT_URI, new String[]{_ID, TITLE, SIZE, DATE_MODIFIED, MIME_TYPE}, null, null, DATE_ADDED + " DESC")));
+        displayNameColumnIndex = cursor.getColumnIndex(TITLE);
+        sizeColumnIndex = cursor.getColumnIndex(SIZE);
+        modifiedColumnIndex = cursor.getColumnIndex(DATE_MODIFIED);
+        mimeTypeColumnIndex = cursor.getColumnIndex(MIME_TYPE);
+        notifyItemRangeInserted(0, getItemCount() + 1);
+    }
+
+    @NonNull
+    @Override
+    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        switch (viewType) {
+            case VIEW_TYPE_ITEM_NATIVE:
+                return new FileNativeItemViewHolder(ItemPickerNativeBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            case VIEW_TYPE_ITEM:
+                return new FileItemViewHolder(ItemAttachmentDefaultBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            default:
+                throw new IllegalStateException("Unknown viewType " + viewType);
+        }
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
+        switch (getItemViewType(position)) {
+            case VIEW_TYPE_ITEM_NATIVE: {
+                ((FileNativeItemViewHolder) holder).bind(openNativePicker);
+                break;
+            }
+            case VIEW_TYPE_ITEM: {
+                if (!cursor.isClosed()) {
+                    bindExecutor.execute(() -> {
+                        final long id = getItemId(position);
+                        final String name = cursor.getString(displayNameColumnIndex);
+                        final String mimeType = cursor.getString(mimeTypeColumnIndex);
+                        final long size = cursor.getLong(sizeColumnIndex);
+                        final long modified = cursor.getLong(modifiedColumnIndex);
+                        new Handler(Looper.getMainLooper()).post(() -> ((FileItemViewHolder) holder).bind(ContentUris.withAppendedId(MediaStore.Files.getContentUri("external"), id), name, mimeType, size, modified, onSelect));
+                    });
+                }
+                break;
+            }
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapterLegacy.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapterLegacy.java
new file mode 100644
index 000000000..1ac14361a
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileAdapterLegacy.java
@@ -0,0 +1,88 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.net.Uri;
+import android.os.Environment;
+import android.util.Pair;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.databinding.ItemAttachmentDefaultBinding;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerNativeBinding;
+import it.niedermann.nextcloud.deck.util.AttachmentUtil;
+
+import static java.util.Collections.reverseOrder;
+import static java.util.Comparator.comparingLong;
+import static java.util.Objects.requireNonNull;
+import static java.util.stream.Collectors.toList;
+
+@Deprecated
+public class FileAdapterLegacy extends AbstractPickerAdapter<RecyclerView.ViewHolder> {
+
+    @NonNull
+    private final List<File> files;
+    @NonNull
+    protected final BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect;
+    @NonNull
+    protected final Runnable openNativePicker;
+
+    public FileAdapterLegacy(@NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable openNativePicker) {
+        // TODO run in separate thread?
+        this.onSelect = onSelect;
+        this.openNativePicker = openNativePicker;
+        this.files = Arrays.stream(requireNonNull(requireNonNull(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)).listFiles()))
+                .sorted(reverseOrder(comparingLong(File::lastModified)))
+                .collect(toList());
+
+    }
+
+    @NonNull
+    @Override
+    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        switch (viewType) {
+            case VIEW_TYPE_ITEM_NATIVE:
+                return new FileNativeItemViewHolder(ItemPickerNativeBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            case VIEW_TYPE_ITEM:
+                return new FileItemViewHolder(ItemAttachmentDefaultBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            default:
+                throw new IllegalStateException("Unknown viewType " + viewType);
+        }
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
+        switch (getItemViewType(position)) {
+            case VIEW_TYPE_ITEM_NATIVE: {
+                ((FileNativeItemViewHolder) holder).bind(openNativePicker);
+                break;
+            }
+            case VIEW_TYPE_ITEM: {
+                final File file = files.get(position - 1);
+                if (file.isFile()) {
+                    ((FileItemViewHolder) holder).bind(Uri.fromFile(file), file.getName(), AttachmentUtil.getMimeType(file.getAbsolutePath()), file.length(), file.lastModified(), onSelect);
+                } else {
+                    ((FileItemViewHolder) holder).bindError();
+                }
+                break;
+            }
+        }
+    }
+
+    @Override
+    public int getItemCount() {
+        return files.size();
+    }
+
+    public void onDestroy() {
+        // Let GarbageCollection do this stuff...
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileItemViewHolder.java
new file mode 100644
index 000000000..f7d64aca8
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileItemViewHolder.java
@@ -0,0 +1,45 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.net.Uri;
+import android.util.Pair;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.ItemAttachmentDefaultBinding;
+
+import static android.text.format.Formatter.formatFileSize;
+import static it.niedermann.nextcloud.deck.util.AttachmentUtil.getIconForMimeType;
+import static it.niedermann.nextcloud.deck.util.DateUtil.getRelativeDateTimeString;
+
+public class FileItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemAttachmentDefaultBinding binding;
+
+    public FileItemViewHolder(@NonNull ItemAttachmentDefaultBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(@NonNull Uri uri, @NonNull String name, String mimeType, long size, long modified, @Nullable BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect) {
+        itemView.setOnClickListener(onSelect == null ? null : (v) -> onSelect.accept(uri, new Pair<>(name, null)));
+        binding.filename.setText(name);
+        binding.filesize.setText(formatFileSize(binding.filesize.getContext(), size));
+        binding.modified.setText(getRelativeDateTimeString(binding.modified.getContext(), modified));
+        binding.preview.setImageResource(getIconForMimeType(mimeType));
+    }
+
+    public void bindError() {
+        binding.filename.setText(R.string.simple_exception);
+        binding.filesize.setText(null);
+        binding.modified.setText(null);
+        itemView.setOnClickListener(null);
+        binding.preview.setImageResource(R.drawable.ic_attach_file_grey600_24dp);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileNativeItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileNativeItemViewHolder.java
new file mode 100644
index 000000000..79129f26a
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/FileNativeItemViewHolder.java
@@ -0,0 +1,23 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.ItemPickerNativeBinding;
+
+public class FileNativeItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemPickerNativeBinding binding;
+
+    public FileNativeItemViewHolder(@NonNull ItemPickerNativeBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(Runnable onOpenMajorPicker) {
+        binding.title.setText(R.string.show_all_files);
+        binding.subtitle.setText(R.string.downloads);
+        itemView.setOnClickListener((v) -> onOpenMajorPicker.run());
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryAdapter.java
new file mode 100644
index 000000000..658eb1ee3
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryAdapter.java
@@ -0,0 +1,100 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.annotation.SuppressLint;
+import android.content.ContentUris;
+import android.content.Context;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.MediaStore;
+import android.util.Pair;
+import android.util.Size;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
+import androidx.lifecycle.LifecycleOwner;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.RequestBuilder;
+
+import java.io.IOException;
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.databinding.ItemAttachmentImageBinding;
+import it.niedermann.nextcloud.deck.databinding.ItemPhotoPreviewBinding;
+
+import static android.os.Build.VERSION.SDK_INT;
+import static android.os.Build.VERSION_CODES.Q;
+import static android.provider.BaseColumns._ID;
+import static android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
+
+public class GalleryAdapter extends AbstractCursorPickerAdapter<RecyclerView.ViewHolder> {
+
+    @NonNull
+    private final LifecycleOwner lifecycleOwner;
+
+    @SuppressLint("InlinedApi")
+    private static final String sortOrder = (SDK_INT >= Q)
+            ? MediaStore.Images.Media.DATE_TAKEN
+            : MediaStore.Images.Media.DATE_ADDED;
+
+    public GalleryAdapter(@NonNull Context context, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect, @NonNull Runnable openNativePicker, @NonNull LifecycleOwner lifecycleOwner) {
+        super(context, onSelect, openNativePicker, EXTERNAL_CONTENT_URI, _ID, sortOrder + " DESC");
+        this.lifecycleOwner = lifecycleOwner;
+        notifyItemRangeInserted(0, getItemCount() + 1);
+    }
+
+    @NonNull
+    @Override
+    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        switch (viewType) {
+            case VIEW_TYPE_ITEM_NATIVE:
+                return new GalleryPhotoPreviewItemViewHolder(ItemPhotoPreviewBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            case VIEW_TYPE_ITEM:
+                return new GalleryItemViewHolder(ItemAttachmentImageBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false));
+            default:
+                throw new IllegalStateException("Unknown viewType " + viewType);
+        }
+
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
+        switch (getItemViewType(position)) {
+            case VIEW_TYPE_ITEM_NATIVE: {
+                ((GalleryPhotoPreviewItemViewHolder) holder).bind(openNativePicker, lifecycleOwner);
+                break;
+            }
+            case VIEW_TYPE_ITEM: {
+                final long id = getItemId(position);
+                bindExecutor.execute(() -> {
+                    try {
+                        final Bitmap thumbnail;
+                        if (SDK_INT >= Q) {
+                            thumbnail = contentResolver.loadThumbnail(ContentUris.withAppendedId(
+                                    EXTERNAL_CONTENT_URI, id), new Size(512, 384), null);
+                        } else {
+                            thumbnail = MediaStore.Images.Thumbnails.getThumbnail(
+                                    contentResolver, id,
+                                    MediaStore.Images.Thumbnails.MINI_KIND, null);
+                        }
+                        new Handler(Looper.getMainLooper()).post(() -> ((GalleryItemViewHolder) holder).bind(ContentUris.withAppendedId(
+                                EXTERNAL_CONTENT_URI, id), thumbnail, onSelect));
+                    } catch (IOException ignored) {
+                        new Handler(Looper.getMainLooper()).post(((GalleryItemViewHolder) holder)::bindError);
+                    }
+                });
+            }
+        }
+    }
+
+    @Override
+    public void onViewDetachedFromWindow(@NonNull RecyclerView.ViewHolder holder) {
+        super.onViewDetachedFromWindow(holder);
+        if (holder instanceof GalleryPhotoPreviewItemViewHolder) {
+            ((GalleryPhotoPreviewItemViewHolder) holder).unbind();
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemDecoration.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemDecoration.java
new file mode 100644
index 000000000..c70dc8277
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemDecoration.java
@@ -0,0 +1,29 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.graphics.Rect;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Px;
+import androidx.recyclerview.widget.RecyclerView;
+
+public class GalleryItemDecoration extends RecyclerView.ItemDecoration {
+
+    @Px
+    private final int gutter;
+
+    public GalleryItemDecoration(@Px int gutter) {
+        this.gutter = gutter;
+    }
+
+    @Override
+    public void getItemOffsets(@NonNull Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
+        final int position = parent.getChildAdapterPosition(view);
+        if (position >= 0) {
+            outRect.left = gutter;
+            outRect.top = gutter;
+            outRect.right = gutter;
+            outRect.bottom = gutter;
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemViewHolder.java
new file mode 100644
index 000000000..346fca9c3
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryItemViewHolder.java
@@ -0,0 +1,42 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.util.Pair;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.bumptech.glide.Glide;
+import com.bumptech.glide.RequestBuilder;
+
+import java.util.function.BiConsumer;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.ItemAttachmentImageBinding;
+
+public class GalleryItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemAttachmentImageBinding binding;
+
+    public GalleryItemViewHolder(@NonNull ItemAttachmentImageBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(@NonNull Uri uri, @Nullable Bitmap image, @NonNull BiConsumer<Uri, Pair<String, RequestBuilder<?>>> onSelect) {
+        itemView.setOnClickListener((v) -> onSelect.accept(uri, new Pair<>(null, Glide.with(itemView.getContext()).load(image))));
+        Glide.with(itemView.getContext())
+                .load(image)
+                .placeholder(R.drawable.ic_image_grey600_24dp)
+                .into(binding.preview);
+    }
+
+    public void bindError() {
+        itemView.setOnClickListener(null);
+        Glide.with(itemView.getContext())
+                .load(R.drawable.ic_image_grey600_24dp)
+                .into(binding.preview);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryPhotoPreviewItemViewHolder.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryPhotoPreviewItemViewHolder.java
new file mode 100644
index 000000000..00a833e57
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/picker/GalleryPhotoPreviewItemViewHolder.java
@@ -0,0 +1,51 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
+
+import androidx.annotation.NonNull;
+import androidx.camera.core.Preview;
+import androidx.camera.lifecycle.ProcessCameraProvider;
+import androidx.core.content.ContextCompat;
+import androidx.lifecycle.LifecycleOwner;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.google.common.util.concurrent.ListenableFuture;
+
+import java.util.concurrent.ExecutionException;
+
+import it.niedermann.nextcloud.deck.DeckLog;
+import it.niedermann.nextcloud.deck.databinding.ItemPhotoPreviewBinding;
+
+import static androidx.camera.core.CameraSelector.DEFAULT_BACK_CAMERA;
+
+public class GalleryPhotoPreviewItemViewHolder extends RecyclerView.ViewHolder {
+
+    private final ItemPhotoPreviewBinding binding;
+    private ProcessCameraProvider cameraProvider;
+
+    public GalleryPhotoPreviewItemViewHolder(@NonNull ItemPhotoPreviewBinding binding) {
+        super(binding.getRoot());
+        this.binding = binding;
+    }
+
+    public void bind(@NonNull Runnable openNativePicker, @NonNull LifecycleOwner lifecycleOwner) {
+        itemView.setOnClickListener((v) -> openNativePicker.run());
+        ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(itemView.getContext());
+        cameraProviderFuture.addListener(() -> {
+            try {
+                unbind();
+                cameraProvider = cameraProviderFuture.get();
+                Preview previewUseCase = new Preview.Builder().build();
+                previewUseCase.setSurfaceProvider(binding.preview.getSurfaceProvider());
+                cameraProvider.bindToLifecycle(lifecycleOwner, DEFAULT_BACK_CAMERA, previewUseCase);
+            } catch (ExecutionException | InterruptedException | IllegalArgumentException e) {
+                DeckLog.logError(e);
+            }
+        }, ContextCompat.getMainExecutor(itemView.getContext()));
+    }
+
+
+    public void unbind() {
+        if (cameraProvider != null) {
+            cameraProvider.unbindAll();
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialog.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialog.java
new file mode 100644
index 000000000..8ebdf1b50
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialog.java
@@ -0,0 +1,102 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.previewdialog;
+
+import android.app.Dialog;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.graphics.Color;
+import android.os.Bundle;
+import android.text.TextUtils;
+import android.view.LayoutInflater;
+
+import androidx.annotation.NonNull;
+import androidx.fragment.app.DialogFragment;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.ViewModelProvider;
+import androidx.swiperefreshlayout.widget.CircularProgressDrawable;
+
+import com.bumptech.glide.RequestBuilder;
+
+import it.niedermann.nextcloud.deck.R;
+import it.niedermann.nextcloud.deck.databinding.DialogPreviewBinding;
+import it.niedermann.nextcloud.deck.ui.branding.BrandedAlertDialogBuilder;
+import it.niedermann.nextcloud.deck.ui.branding.BrandedDialogFragment;
+
+import static android.view.View.GONE;
+import static android.view.View.VISIBLE;
+import static it.niedermann.nextcloud.deck.DeckApplication.isDarkTheme;
+
+public class PreviewDialog extends BrandedDialogFragment {
+
+    private DialogPreviewBinding binding;
+    private PreviewDialogViewModel viewModel;
+    private LiveData<RequestBuilder<?>> imageBuilder$;
+    private LiveData<String> title$;
+
+    @NonNull
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        viewModel = new ViewModelProvider(requireActivity()).get(PreviewDialogViewModel.class);
+        binding = DialogPreviewBinding.inflate(LayoutInflater.from(requireContext()));
+
+        final Context context = requireContext();
+
+        this.imageBuilder$ = this.viewModel.getImageBuilder();
+        this.imageBuilder$.observe(requireActivity(), builder -> {
+            if (builder == null) {
+                binding.avatar.setVisibility(GONE);
+            } else {
+                final CircularProgressDrawable circularProgressDrawable = new CircularProgressDrawable(context);
+                circularProgressDrawable.setStrokeWidth(5f);
+                circularProgressDrawable.setCenterRadius(30f);
+                circularProgressDrawable.setColorSchemeColors(isDarkTheme(context) ? Color.LTGRAY : Color.DKGRAY);
+                circularProgressDrawable.start();
+                binding.avatar.setVisibility(VISIBLE);
+                binding.avatar.post(() -> builder
+                        .placeholder(circularProgressDrawable)
+                        .into(binding.avatar));
+            }
+        });
+        this.title$ = this.viewModel.getTitle();
+        this.title$.observe(requireActivity(), title -> {
+            if (TextUtils.isEmpty(title)) {
+                binding.title.setVisibility(GONE);
+            } else {
+                binding.title.setVisibility(VISIBLE);
+                binding.title.setText(title);
+            }
+        });
+
+        return new BrandedAlertDialogBuilder(requireContext())
+                .setPositiveButton(R.string.simple_attach, (d, w) -> {
+                    viewModel.setResult(true);
+                    dismiss();
+                })
+                .setNeutralButton(R.string.simple_close, (d, w) -> {
+                    viewModel.setResult(false);
+                    dismiss();
+                })
+                .setView(binding.getRoot())
+                .create();
+    }
+
+    @Override
+    public void onCancel(@NonNull DialogInterface dialog) {
+        viewModel.setResult(false);
+        super.onCancel(dialog);
+    }
+
+    @Override
+    public void applyBrand(int mainColor) {
+    }
+
+    @Override
+    public void onDestroy() {
+        this.imageBuilder$.removeObservers(requireActivity());
+        this.title$.removeObservers(requireActivity());
+        super.onDestroy();
+    }
+
+    public static DialogFragment newInstance() {
+        return new PreviewDialog();
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialogViewModel.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialogViewModel.java
new file mode 100644
index 000000000..8ee8a0e08
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/card/attachments/previewdialog/PreviewDialogViewModel.java
@@ -0,0 +1,50 @@
+package it.niedermann.nextcloud.deck.ui.card.attachments.previewdialog;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.ViewModel;
+
+import com.bumptech.glide.RequestBuilder;
+
+import static androidx.lifecycle.Transformations.distinctUntilChanged;
+
+public class PreviewDialogViewModel extends ViewModel {
+
+    @NonNull
+    private final MutableLiveData<String> title$ = new MutableLiveData<>();
+    @NonNull
+    private final MutableLiveData<RequestBuilder<?>> imageBuilder$ = new MutableLiveData<>();
+    private MutableLiveData<Boolean> result$ = new MutableLiveData<>();
+
+    /**
+     * Call this before observing {@link #getResult()} to prepare the {@link PreviewDialog}.
+     */
+    public void prepareDialog(@Nullable String title, @Nullable RequestBuilder<?> imageBuilder) {
+        this.result$ = new MutableLiveData<>();
+        this.title$.setValue(title);
+        this.imageBuilder$.setValue(imageBuilder);
+    }
+
+    /**
+     * This will be a new instance after each call of {@link #prepareDialog(String, RequestBuilder)}.
+     *
+     * @return {@link Boolean#TRUE} if a positive action has been submitted, {@link Boolean#FALSE} if the dialog has been canceled.
+     */
+    public LiveData<Boolean> getResult() {
+        return this.result$;
+    }
+
+    protected LiveData<String> getTitle() {
+        return distinctUntilChanged(this.title$);
+    }
+
+    protected LiveData<RequestBuilder<?>> getImageBuilder() {
+        return distinctUntilChanged(this.imageBuilder$);
+    }
+
+    protected void setResult(boolean submittedPositive) {
+        result$.setValue(submittedPositive);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterUserAdapter.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterUserAdapter.java
index 82230060c..4b75b985f 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterUserAdapter.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/filter/FilterUserAdapter.java
@@ -84,14 +84,14 @@ public class FilterUserAdapter extends RecyclerView.Adapter<FilterUserAdapter.Us
         }
 
         void bind(@NonNull final User user) {
-            binding.displayName.setText(user.getDisplayname());
+            binding.title.setText(user.getDisplayname());
             ViewUtil.addAvatar(binding.avatar, account.getUrl(), user.getUid(), avatarSize, R.drawable.ic_person_grey600_24dp);
             itemView.setSelected(selectedUsers.contains(user));
             bindClickListener(user);
         }
 
         public void bindNotAssigned() {
-            binding.displayName.setText(itemView.getContext().getString(R.string.simple_unassigned));
+            binding.title.setText(itemView.getContext().getString(R.string.simple_unassigned));
             Glide.with(itemView.getContext())
                     .load(R.drawable.ic_baseline_block_24)
                     .into(binding.avatar);
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoActivity.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoActivity.java
new file mode 100644
index 000000000..af17464dc
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoActivity.java
@@ -0,0 +1,182 @@
+package it.niedermann.nextcloud.deck.ui.takephoto;
+
+import android.content.Context;
+import android.content.Intent;
+import android.content.res.ColorStateList;
+import android.net.Uri;
+import android.os.Bundle;
+import android.util.Size;
+import android.view.OrientationEventListener;
+import android.view.Surface;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.RequiresApi;
+import androidx.camera.core.Camera;
+import androidx.camera.core.ImageCapture;
+import androidx.camera.core.ImageCaptureException;
+import androidx.camera.core.Preview;
+import androidx.camera.lifecycle.ProcessCameraProvider;
+import androidx.core.content.ContextCompat;
+import androidx.lifecycle.ViewModelProvider;
+
+import com.google.common.util.concurrent.ListenableFuture;
+
+import java.io.File;
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.format.DateTimeFormatter;
+import java.util.concurrent.ExecutionException;
+
+import it.niedermann.nextcloud.deck.DeckLog;
+import it.niedermann.nextcloud.deck.databinding.ActivityTakePhotoBinding;
+import it.niedermann.nextcloud.deck.ui.branding.BrandedActivity;
+import it.niedermann.nextcloud.deck.ui.exception.ExceptionDialogFragment;
+import it.niedermann.nextcloud.deck.ui.exception.ExceptionHandler;
+import it.niedermann.nextcloud.deck.util.AttachmentUtil;
+
+import static android.os.Build.VERSION_CODES.LOLLIPOP;
+import static it.niedermann.nextcloud.deck.util.MimeTypeUtil.IMAGE_JPEG;
+
+@RequiresApi(LOLLIPOP)
+public class TakePhotoActivity extends BrandedActivity {
+
+    private ActivityTakePhotoBinding binding;
+    private TakePhotoViewModel viewModel;
+
+    private View[] brandedViews;
+
+    private ListenableFuture<ProcessCameraProvider> cameraProviderFuture;
+    private OrientationEventListener orientationEventListener;
+
+    private final DateTimeFormatter fileNameFromCameraFormatter = DateTimeFormatter.ofPattern("'JPG_'yyyyMMdd'_'HHmmss'.jpg'");
+
+    @Override
+    protected void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        Thread.currentThread().setUncaughtExceptionHandler(new ExceptionHandler(this));
+
+        binding = ActivityTakePhotoBinding.inflate(getLayoutInflater());
+        viewModel = new ViewModelProvider(this).get(TakePhotoViewModel.class);
+
+        setContentView(binding.getRoot());
+
+        cameraProviderFuture = ProcessCameraProvider.getInstance(this);
+        cameraProviderFuture.addListener(() -> {
+            try {
+                final ProcessCameraProvider cameraProvider = cameraProviderFuture.get();
+                final Preview previewUseCase = getPreviewUseCase();
+                final ImageCapture captureUseCase = getCaptureUseCase();
+                final Camera camera = cameraProvider.bindToLifecycle(this, viewModel.getCameraSelector(), captureUseCase, previewUseCase);
+
+                viewModel.getCameraSelectorToggleButtonImageResource().observe(this, res -> binding.switchCamera.setImageDrawable(ContextCompat.getDrawable(this, res)));
+                viewModel.getTorchToggleButtonImageResource().observe(this, res -> binding.toggleTorch.setImageDrawable(ContextCompat.getDrawable(this, res)));
+                viewModel.isTorchEnabled().observe(this, enabled -> camera.getCameraControl().enableTorch(enabled));
+
+                binding.toggleTorch.setOnClickListener((v) -> viewModel.toggleTorchEnabled());
+                binding.switchCamera.setOnClickListener((v) -> {
+                    viewModel.toggleCameraSelector();
+                    cameraProvider.unbindAll();
+                    cameraProvider.bindToLifecycle(this, viewModel.getCameraSelector(), captureUseCase, previewUseCase);
+                });
+            } catch (ExecutionException | InterruptedException e) {
+                DeckLog.logError(e);
+                finish();
+            }
+        }, ContextCompat.getMainExecutor(this));
+
+        brandedViews = new View[]{binding.takePhoto, binding.switchCamera, binding.toggleTorch};
+    }
+
+    private ImageCapture getCaptureUseCase() {
+        final ImageCapture captureUseCase = new ImageCapture.Builder().setTargetResolution(new Size(720, 1280)).build();
+
+        orientationEventListener = new OrientationEventListener(this) {
+            @Override
+            public void onOrientationChanged(int orientation) {
+                int rotation;
+
+                // Monitors orientation values to determine the target rotation value
+                if (orientation >= 45 && orientation < 135) {
+                    rotation = Surface.ROTATION_270;
+                } else if (orientation >= 135 && orientation < 225) {
+                    rotation = Surface.ROTATION_180;
+                } else if (orientation >= 225 && orientation < 315) {
+                    rotation = Surface.ROTATION_90;
+                } else {
+                    rotation = Surface.ROTATION_0;
+                }
+
+                captureUseCase.setTargetRotation(rotation);
+            }
+        };
+        orientationEventListener.enable();
+
+        binding.takePhoto.setOnClickListener((v) -> {
+            binding.takePhoto.setEnabled(false);
+            final String photoFileName = Instant.now().atZone(ZoneId.systemDefault()).format(fileNameFromCameraFormatter);
+            try {
+                final File photoFile = AttachmentUtil.getTempCacheFile(this, "photos/" + photoFileName);
+                final ImageCapture.OutputFileOptions options = new ImageCapture.OutputFileOptions.Builder(photoFile).build();
+                captureUseCase.takePicture(options, ContextCompat.getMainExecutor(this), new ImageCapture.OnImageSavedCallback() {
+                    @Override
+                    public void onImageSaved(@NonNull ImageCapture.OutputFileResults outputFileResults) {
+                        final Uri savedUri = Uri.fromFile(photoFile);
+                        DeckLog.info("onImageSaved - savedUri: " + savedUri.toString());
+                        setResult(RESULT_OK, new Intent().setDataAndType(savedUri, IMAGE_JPEG));
+                        finish();
+                    }
+
+                    @Override
+                    public void onError(@NonNull ImageCaptureException e) {
+                        e.printStackTrace();
+                        //noinspection ResultOfMethodCallIgnored
+                        photoFile.delete();
+                        binding.takePhoto.setEnabled(true);
+                    }
+                });
+            } catch (Exception e) {
+                ExceptionDialogFragment.newInstance(e, null).show(getSupportFragmentManager(), ExceptionDialogFragment.class.getSimpleName());
+            }
+        });
+
+        return captureUseCase;
+    }
+
+    private Preview getPreviewUseCase() {
+        Preview previewUseCase = new Preview.Builder().build();
+        previewUseCase.setSurfaceProvider(binding.preview.getSurfaceProvider());
+        return previewUseCase;
+    }
+
+    @Override
+    protected void onPause() {
+        if (this.orientationEventListener != null) {
+            this.orientationEventListener.disable();
+        }
+        super.onPause();
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        if (this.orientationEventListener != null) {
+            this.orientationEventListener.enable();
+        }
+    }
+
+    @RequiresApi(LOLLIPOP)
+    public static Intent createIntent(@NonNull Context context) {
+        return new Intent(context, TakePhotoActivity.class).setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
+    }
+
+    @Override
+    public void applyBrand(int mainColor) {
+        final ColorStateList colorStateList = ColorStateList.valueOf(mainColor);
+        for (View v : brandedViews) {
+            v.setBackgroundTintList(colorStateList);
+        }
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoViewModel.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoViewModel.java
new file mode 100644
index 000000000..a71291ff2
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/takephoto/TakePhotoViewModel.java
@@ -0,0 +1,57 @@
+package it.niedermann.nextcloud.deck.ui.takephoto;
+
+import androidx.annotation.NonNull;
+import androidx.camera.core.CameraSelector;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.Transformations;
+import androidx.lifecycle.ViewModel;
+
+import it.niedermann.nextcloud.deck.R;
+
+import static androidx.camera.core.CameraSelector.DEFAULT_BACK_CAMERA;
+import static androidx.camera.core.CameraSelector.DEFAULT_FRONT_CAMERA;
+
+public class TakePhotoViewModel extends ViewModel {
+
+    @NonNull
+    private CameraSelector cameraSelector = DEFAULT_BACK_CAMERA;
+    @NonNull
+    private final MutableLiveData<Integer> cameraSelectorToggleButtonImageResource = new MutableLiveData<>(R.drawable.ic_baseline_camera_front_24);
+    @NonNull
+    private final MutableLiveData<Boolean> torchEnabled = new MutableLiveData<>(false);
+
+    @NonNull
+    public CameraSelector getCameraSelector() {
+        return this.cameraSelector;
+    }
+
+    public LiveData<Integer> getCameraSelectorToggleButtonImageResource() {
+        return this.cameraSelectorToggleButtonImageResource;
+    }
+
+    public void toggleCameraSelector() {
+        if (this.cameraSelector == DEFAULT_BACK_CAMERA) {
+            this.cameraSelector = DEFAULT_FRONT_CAMERA;
+            this.cameraSelectorToggleButtonImageResource.postValue(R.drawable.ic_baseline_camera_rear_24);
+        } else {
+            this.cameraSelector = DEFAULT_BACK_CAMERA;
+            this.cameraSelectorToggleButtonImageResource.postValue(R.drawable.ic_baseline_camera_front_24);
+        }
+    }
+
+    public void toggleTorchEnabled() {
+        //noinspection ConstantConditions
+        this.torchEnabled.postValue(!this.torchEnabled.getValue());
+    }
+
+    public LiveData<Boolean> isTorchEnabled() {
+        return this.torchEnabled;
+    }
+
+    public LiveData<Integer> getTorchToggleButtonImageResource() {
+        return Transformations.map(isTorchEnabled(), enabled -> enabled
+                ? R.drawable.ic_baseline_flash_off_24
+                : R.drawable.ic_baseline_flash_on_24);
+    }
+}
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/ui/view/SquareConstraintLayout.java b/app/src/main/java/it/niedermann/nextcloud/deck/ui/view/SquareConstraintLayout.java
new file mode 100644
index 000000000..0912a07dd
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/ui/view/SquareConstraintLayout.java
@@ -0,0 +1,35 @@
+package it.niedermann.nextcloud.deck.ui.view;
+
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.os.Build;
+import android.util.AttributeSet;
+
+import androidx.constraintlayout.widget.ConstraintLayout;
+
+public class SquareConstraintLayout extends ConstraintLayout {
+
+    public SquareConstraintLayout(Context context) {
+        super(context);
+    }
+
+    public SquareConstraintLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public SquareConstraintLayout(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    public SquareConstraintLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
+        super(context, attrs, defStyleAttr, defStyleRes);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        // Set a square layout.
+        super.onMeasure(widthMeasureSpec, widthMeasureSpec);
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/util/AttachmentUtil.java b/app/src/main/java/it/niedermann/nextcloud/deck/util/AttachmentUtil.java
index 844a301e8..2baec8e92 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/util/AttachmentUtil.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/util/AttachmentUtil.java
@@ -3,8 +3,11 @@ package it.niedermann.nextcloud.deck.util;
 import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
+import android.text.TextUtils;
+import android.webkit.MimeTypeMap;
 import android.widget.Toast;
 
+import androidx.annotation.DrawableRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -58,34 +61,78 @@ public class AttachmentUtil {
         return accountUrl + "/index.php/apps/deck/cards/" + cardRemoteId + "/attachment/" + attachmentRemoteId;
     }
 
-    public static File copyContentUriToTempFile(@NonNull Context context, @NonNull Uri currentUri, long accountId, Long localId) throws IOException, IllegalArgumentException {
-        String fullTempPath = context.getApplicationContext().getFilesDir().getAbsolutePath() + "/attachments/account-" + accountId + "/card-" + (localId == null ? "pending-creation" : localId) + '/' + UriUtils.getDisplayNameForUri(currentUri, context);
-        DeckLog.verbose("----- fullTempPath: " + fullTempPath);
-        InputStream inputStream = context.getContentResolver().openInputStream(currentUri);
+    public static File copyContentUriToTempFile(@NonNull Context context, @NonNull Uri currentUri, long accountId, Long localCardId) throws IOException, IllegalArgumentException {
+        final InputStream inputStream = context.getContentResolver().openInputStream(currentUri);
         if (inputStream == null) {
             throw new IOException("Could not open input stream for " + currentUri.getPath());
         }
-        File cacheFile = new File(fullTempPath);
-        File tempDir = cacheFile.getParentFile();
+        final File cacheFile = getTempCacheFile(context, "attachments/account-" + accountId + "/card-" + (localCardId == null ? "pending-creation" : localCardId) + '/' + UriUtils.getDisplayNameForUri(currentUri, context));
+        final FileOutputStream outputStream = new FileOutputStream(cacheFile);
+        byte[] buffer = new byte[4096];
+
+        int count;
+        while ((count = inputStream.read(buffer)) > 0) {
+            outputStream.write(buffer, 0, count);
+        }
+        DeckLog.verbose("----- wrote");
+        return cacheFile;
+    }
+
+    /**
+     * Creates a new {@link File}
+     */
+    public static File getTempCacheFile(@NonNull Context context, String fileName) throws IOException {
+        File cacheFile = new File(context.getApplicationContext().getFilesDir().getAbsolutePath() + "/" + fileName);
+
+        DeckLog.verbose("- Full path for new cache file: " + cacheFile.getAbsolutePath());
+
+        final File tempDir = cacheFile.getParentFile();
         if (tempDir == null) {
-            throw new FileNotFoundException("could not cacheFile.getPranetFile()");
+            throw new FileNotFoundException("could not cacheFile.getParentFile()");
         }
         if (!tempDir.exists()) {
-            if (!tempDir.mkdirs()) {
+            DeckLog.verbose("-- The folder in which the new file should be created does not exist yet. Trying to create it...");
+            if (tempDir.mkdirs()) {
+                DeckLog.verbose("--- Creation successful");
+            } else {
                 throw new IOException("Directory for temporary file does not exist and could not be created.");
             }
         }
-        if (!cacheFile.createNewFile()) {
+
+        DeckLog.verbose("- Try to create actual cache file");
+        if (cacheFile.createNewFile()) {
+            DeckLog.verbose("-- Successfully created cache file");
+        } else {
             throw new IOException("Failed to create cacheFile");
         }
-        FileOutputStream outputStream = new FileOutputStream(fullTempPath);
-        byte[] buffer = new byte[4096];
 
-        int count;
-        while ((count = inputStream.read(buffer)) > 0) {
-            outputStream.write(buffer, 0, count);
-        }
-        DeckLog.verbose("----- wrote");
         return cacheFile;
     }
+
+    @DrawableRes
+    public static int getIconForMimeType(@NonNull String mimeType) {
+        if (TextUtils.isEmpty(mimeType)) {
+            return R.drawable.ic_attach_file_grey600_24dp;
+        } else if (MimeTypeUtil.isAudio(mimeType)) {
+            return R.drawable.ic_music_note_grey600_24dp;
+        } else if (MimeTypeUtil.isVideo(mimeType)) {
+            return R.drawable.ic_local_movies_grey600_24dp;
+        } else if (MimeTypeUtil.isPdf(mimeType)) {
+            return R.drawable.ic_baseline_picture_as_pdf_24;
+        } else if (MimeTypeUtil.isContact(mimeType)) {
+            return R.drawable.ic_baseline_contact_mail_24;
+        } else {
+            return R.drawable.ic_attach_file_grey600_24dp;
+        }
+    }
+
+    public static String getMimeType(@Nullable String url) {
+        String type = null;
+        String extension = MimeTypeMap.getFileExtensionFromUrl(url);
+        if (extension != null) {
+            type = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
+        }
+        return type;
+    }
+
 }
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/util/MimeTypeUtil.java b/app/src/main/java/it/niedermann/nextcloud/deck/util/MimeTypeUtil.java
index 0390bf96d..04694a058 100644
--- a/app/src/main/java/it/niedermann/nextcloud/deck/util/MimeTypeUtil.java
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/util/MimeTypeUtil.java
@@ -6,6 +6,7 @@ import java.util.Locale;
 
 public class MimeTypeUtil {
 
+    public static final String IMAGE_JPEG = "image/jpeg";
     public static final String TEXT_PLAIN = "text/plain";
     public static final String TEXT_VCARD = "text/vcard";
     public static final String APPLICATION_PDF = "application/pdf";
diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/util/VCardUtil.java b/app/src/main/java/it/niedermann/nextcloud/deck/util/VCardUtil.java
new file mode 100644
index 000000000..274af332d
--- /dev/null
+++ b/app/src/main/java/it/niedermann/nextcloud/deck/util/VCardUtil.java
@@ -0,0 +1,42 @@
+package it.niedermann.nextcloud.deck.util;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.Cursor;
+import android.graphics.Color;
+import android.net.Uri;
+import android.provider.ContactsContract;
+
+import androidx.annotation.ColorInt;
+import androidx.annotation.NonNull;
+
+import java.util.NoSuchElementException;
+import java.util.Objects;
+
+import it.niedermann.nextcloud.deck.R;
+
+public class VCardUtil {
+
+    private VCardUtil() {
+        // You shall not pass
+    }
+
+    public static Uri getVCardContentUri(@NonNull Context context, @NonNull Uri contactUri) throws NoSuchElementException {
+        final ContentResolver cr = context.getContentResolver();
+        try (final Cursor cursor = cr.query(contactUri, null, null, null, null)) {
+            if (cursor != null && cursor.moveToFirst()) {
+                final String lookupKey = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.LOOKUP_KEY));
+                return Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_VCARD_URI, lookupKey);
+            } else {
+                throw new NoSuchElementException("Cursor has zero entries");
+            }
+        }
+    }
+
+    @ColorInt
+    public static int getColorBasedOnDisplayName(@NonNull Context context, @NonNull String displayName) {
+        final String[] colors = context.getResources().getStringArray(R.array.board_default_colors);
+        final int hashCode = Objects.hashCode(displayName);
+        return Color.parseColor(colors[(hashCode < 0 ? hashCode * -1 : hashCode) % colors.length]);
+    }
+}