Performant image picker

Signed-off-by: Stefan Niedermann <info@niedermann.it>

4 files changed, 138 insertions, 63 deletions

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 990328f66..9edcf7a33 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
@@ -4,12 +4,10 @@ import android.content.ContentResolver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.ColorStateList;
-import android.database.Cursor;
 import android.graphics.Color;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.ContactsContract;
-import android.provider.MediaStore;
 import android.util.DisplayMetrics;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -34,8 +32,6 @@ import com.nextcloud.android.sso.exceptions.NextcloudHttpRequestFailedException;
 import java.io.File;
 import java.io.IOException;
 import java.time.Instant;
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 
@@ -156,12 +152,13 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
             public void onStateChanged(@NonNull View bottomSheet, int newState) {
                 switch (newState) {
                     case STATE_HIDDEN: {
-                        binding.bottomNavigation.setVisibility(GONE);
+                        hidePicker();
+                        binding.fab.show();
                         break;
                     }
                     case STATE_EXPANDED:
                     case STATE_HALF_EXPANDED: {
-                        binding.bottomNavigation.setVisibility(VISIBLE);
+                        showPicker();
                         break;
                     }
                 }
@@ -172,20 +169,11 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
 
             }
         });
-        GalleryAdapter galleryAdapter = new GalleryAdapter();
-        List<Long> imageIds = Collections.emptyList();
         if (SDK_INT >= LOLLIPOP) {
-            final ContentResolver contentResolver = requireContext().getContentResolver();
-            try (final Cursor outerCursor = contentResolver.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, null, null, null, null)) {
-                imageIds = new ArrayList<>(outerCursor.getCount());
-                while (outerCursor.moveToNext()) {
-                    imageIds.add(outerCursor.getLong(outerCursor.getColumnIndex(MediaStore.Images.Media._ID)));
-                }
-            }
+            GalleryAdapter galleryAdapter = new GalleryAdapter(requireContext());
+            binding.pickerRecyclerView.setLayoutManager(new GridLayoutManager(requireContext(), 3));
+            binding.pickerRecyclerView.setAdapter(galleryAdapter);
         }
-        binding.pickerRecyclerView.setLayoutManager(new GridLayoutManager(requireContext(), 3));
-        galleryAdapter.setImageIds(imageIds);
-        binding.pickerRecyclerView.setAdapter(galleryAdapter);
 
         final DisplayMetrics displayMetrics = getResources().getDisplayMetrics();
         int spanCount = (int) ((displayMetrics.widthPixels / displayMetrics.density) / getResources().getInteger(R.integer.max_dp_attachment_column));
@@ -224,7 +212,8 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
 //                picker = CardAttachmentPicker.newInstance();
 //                picker.show(getChildFragmentManager(), CardAttachmentPicker.class.getSimpleName());
                 mBottomSheetBehaviour.setState(STATE_HALF_EXPANDED);
-                binding.bottomNavigation.setVisibility(VISIBLE);
+                showPicker();
+                binding.fab.hide();
             });
             binding.fab.show();
             binding.attachmentsList.addOnScrollListener(new RecyclerView.OnScrollListener() {
@@ -419,6 +408,24 @@ public class CardAttachmentsFragment extends BrandedFragment implements Attachme
         }
     }
 
+    private void hidePicker() {
+        binding.bottomNavigation
+                .animate()
+                .translationY(binding.bottomNavigation.getHeight())
+                .setDuration(300)
+                .start();
+        binding.bottomNavigation.setVisibility(GONE);
+    }
+
+    private void showPicker() {
+        binding.bottomNavigation.setVisibility(VISIBLE);
+        binding.bottomNavigation
+                .animate()
+                .translationY(0)
+                .setDuration(300)
+                .start();
+    }
+
     @Override
     public void onAttachmentDeleted(Attachment attachment) {
         adapter.removeAttachment(attachment);
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
index faad73e8a..d123cee74 100644
--- 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
@@ -1,35 +1,75 @@
 package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
 
+import android.annotation.SuppressLint;
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.Context;
+import android.database.Cursor;
+import android.graphics.Bitmap;
+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 android.widget.Toast;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.recyclerview.widget.RecyclerView;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.NoSuchElementException;
+import java.util.Objects;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.FutureTask;
 
+import it.niedermann.nextcloud.deck.DeckLog;
 import it.niedermann.nextcloud.deck.databinding.ItemAttachmentImageBinding;
 
+import static android.os.Build.VERSION.SDK_INT;
+import static android.os.Build.VERSION_CODES.Q;
+import static androidx.recyclerview.widget.RecyclerView.NO_ID;
+
 public class GalleryAdapter extends RecyclerView.Adapter<GalleryItemViewHolder> {
 
     @NonNull
-    List<Long> imageIds = new ArrayList<>();
+    private final Context context;
+    private final int columnIndex;
+    private final int count;
+    @Nullable
+    private final Cursor cursor;
+    @NonNull
+    private final ContentResolver contentResolver;
+    @NonNull
+    private final Map<Integer, Pair<Long, FutureTask<Bitmap>>> itemCache = new HashMap<>();
+    private final ExecutorService bitmapFetcherExecutor = Executors.newCachedThreadPool();
+    private final ExecutorService bitmapWaiterExecutor = Executors.newCachedThreadPool();
 
-    public GalleryAdapter() {
-        setHasStableIds(true);
-    }
+    public GalleryAdapter(@NonNull Context context) {
+        this.context = context;
+        this.contentResolver = context.getContentResolver();
+        log("Start Query");
+        @SuppressLint("InlinedApi") final String sortOrder = (SDK_INT >= Q)
+                ? MediaStore.Images.Media.DATE_TAKEN
+                : MediaStore.Images.Media.DATE_ADDED;
+        cursor = Objects.requireNonNull(contentResolver.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, new String[]{MediaStore.Images.Media._ID}, null, null, sortOrder + " DESC"));
+        this.columnIndex = cursor.getColumnIndex(MediaStore.Images.Media._ID);
+        this.count = cursor.getCount();
 
-    public void setImageIds(@NonNull Collection<Long> imageIds) {
-        this.imageIds.clear();
-        this.imageIds.addAll(imageIds);
-        notifyDataSetChanged();
+        log("Cursor count = " + this.count);
+        notifyItemRangeInserted(0, this.count);
+        setHasStableIds(true);
     }
 
     @Override
     public long getItemId(int position) {
-        return super.getItemId(position);
+        Pair<Long, ?> itemAtPosition = getImageId(position);
+        return itemAtPosition == null ? NO_ID : itemAtPosition.first;
     }
 
     @NonNull
@@ -40,11 +80,50 @@ public class GalleryAdapter extends RecyclerView.Adapter<GalleryItemViewHolder>
 
     @Override
     public void onBindViewHolder(@NonNull GalleryItemViewHolder holder, int position) {
-        holder.bind(imageIds.get(position));
+        FutureTask<Bitmap> imageFuture = getImageId(position).second;
+        bitmapFetcherExecutor.execute(imageFuture);
+        bitmapWaiterExecutor.execute(() -> {
+            try {
+                final Bitmap image = imageFuture.get();
+                new Handler(Looper.getMainLooper()).post(() -> holder.bind(image));
+            } catch (ExecutionException | InterruptedException ignored) {
+                new Handler(Looper.getMainLooper()).post(() -> holder.bind(null));
+            }
+        });
     }
 
     @Override
     public int getItemCount() {
-        return this.imageIds.size();
+        return count;
+    }
+
+    private Pair<Long, FutureTask<Bitmap>> getImageId(int position) {
+        if (itemCache.containsKey(position)) {
+            return itemCache.get(position);
+        } else {
+            if (cursor == null) {
+                return new Pair<>(NO_ID, null);
+            }
+            if (cursor.moveToPosition(position)) {
+                long id = cursor.getLong(columnIndex);
+                return itemCache.put(position, new Pair<>(id, new FutureTask<>(() -> {
+                    if (SDK_INT >= Q) {
+                        return contentResolver.loadThumbnail(ContentUris.withAppendedId(
+                                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, id), new Size(512, 384), null);
+                    } else {
+                        return MediaStore.Images.Thumbnails.getThumbnail(
+                                contentResolver, id,
+                                MediaStore.Images.Thumbnails.MINI_KIND, null);
+                    }
+                })));
+            } else {
+                throw new NoSuchElementException("Could not find ID for position " + position);
+            }
+        }
+    }
+
+    private void log(String msg) {
+        DeckLog.log(msg);
+        Toast.makeText(context, msg, Toast.LENGTH_SHORT).show();
     }
 }
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
index 7a409c748..7c4cf4a5a 100644
--- 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
@@ -1,30 +1,31 @@
 package it.niedermann.nextcloud.deck.ui.card.attachments.picker;
 
-import android.content.Context;
-import android.provider.MediaStore;
+import android.graphics.Bitmap;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.recyclerview.widget.RecyclerView;
 
 import com.bumptech.glide.Glide;
 
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
 import it.niedermann.nextcloud.deck.databinding.ItemAttachmentImageBinding;
 
 public class GalleryItemViewHolder extends RecyclerView.ViewHolder {
 
-    ItemAttachmentImageBinding binding;
+    private final ExecutorService executor = Executors.newCachedThreadPool();
+    private final ItemAttachmentImageBinding binding;
 
     public GalleryItemViewHolder(@NonNull ItemAttachmentImageBinding binding) {
         super(binding.getRoot());
         this.binding = binding;
     }
 
-    public void bind(@NonNull Long imageId) {
-        Context context = itemView.getContext();
-        Glide.with(context)
-                .load(MediaStore.Images.Thumbnails.getThumbnail(
-                        context.getContentResolver(), imageId,
-                        MediaStore.Images.Thumbnails.MINI_KIND, null))
+    public void bind(@Nullable Bitmap image) {
+        Glide.with(itemView.getContext())
+                .load(image)
                 .into(binding.preview);
     }
 }
diff --git a/app/src/main/res/layout/fragment_card_edit_tab_attachments.xml b/app/src/main/res/layout/fragment_card_edit_tab_attachments.xml
index c08656c60..cc02d4b3b 100644
--- a/app/src/main/res/layout/fragment_card_edit_tab_attachments.xml
+++ b/app/src/main/res/layout/fragment_card_edit_tab_attachments.xml
@@ -37,48 +37,36 @@
         tools:visibility="visible" />
 
     <LinearLayout
-        android:orientation="vertical"
         android:id="@+id/bottom_sheet_parent"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:background="@android:color/white"
         android:gravity="center"
+        android:orientation="vertical"
         app:elevation="@dimen/spacer_1x"
         app:layout_behavior="com.google.android.material.bottomsheet.BottomSheetBehavior">
 
         <View
             android:layout_width="20dp"
             android:layout_height="4dp"
-            android:background="@color/bg_info_box"
             android:layout_marginTop="10dp"
-            android:layout_marginBottom="10dp"/>
+            android:layout_marginBottom="10dp"
+            android:background="@color/bg_info_box" />
 
-        <androidx.core.widget.NestedScrollView
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/pickerRecyclerView"
             android:layout_width="match_parent"
-            android:layout_height="wrap_content">
-
-            <LinearLayout
-                android:id="@+id/bottom_view"
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:orientation="vertical">
-
-                <androidx.recyclerview.widget.RecyclerView
-                    android:id="@+id/pickerRecyclerView"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    tools:listitem="@layout/support_simple_spinner_dropdown_item"/>
-
-            </LinearLayout>
-        </androidx.core.widget.NestedScrollView>
+            android:layout_height="wrap_content"
+            tools:listitem="@layout/support_simple_spinner_dropdown_item" />
     </LinearLayout>
 
     <LinearLayout
         android:id="@+id/bottomNavigation"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
+        android:gravity="bottom"
         android:visibility="gone"
-        android:gravity="bottom">
+        tools:visibility="visible">
 
         <com.google.android.flexbox.FlexboxLayout
             android:layout_width="match_parent"