UI: Move rename buffer management to new view base class

Renaming is a nice example of a feature that shouldn't need a specific
implementation for a specific view type (e.g. grid or tree view). So it's
something that can be supported in the general view code. Individual views can
use it "for free" then. This ports the view level part of the renaming code,
the view item level part of it can be ported once we have a common base class
for the view items.

2 files changed, 62 insertions, 25 deletions

diff --git a/source/blender/editors/interface/abstract_view.cc b/source/blender/editors/interface/abstract_view.cc
index 542d82a56a3..dea9600fde4 100644
--- a/source/blender/editors/interface/abstract_view.cc
+++ b/source/blender/editors/interface/abstract_view.cc
@@ -27,7 +27,7 @@ void AbstractView::update_from_old(uiBlock &new_block)
     return;
   }
 
-  const uiViewHandle *old_view_handle = ui_block_view_find_matching_in_old_block(
+  uiViewHandle *old_view_handle = ui_block_view_find_matching_in_old_block(
       &new_block, reinterpret_cast<uiViewHandle *>(this));
   if (old_view_handle == nullptr) {
     /* Initial construction, nothing to update. */
@@ -35,7 +35,15 @@ void AbstractView::update_from_old(uiBlock &new_block)
     return;
   }
 
-  update_children_from_old(reinterpret_cast<const AbstractView &>(*old_view_handle));
+  AbstractView &old_view = reinterpret_cast<AbstractView &>(*old_view_handle);
+
+  /* Update own persistent data. */
+  /* Keep the rename buffer persistent while renaming! The rename button uses the buffer's
+   * pointer to identify itself over redraws. */
+  rename_buffer_ = std::move(old_view.rename_buffer_);
+  old_view.rename_buffer_ = nullptr;
+
+  update_children_from_old(old_view);
 
   /* Finished (re-)constructing the tree. */
   is_reconstructed_ = true;
@@ -43,10 +51,52 @@ void AbstractView::update_from_old(uiBlock &new_block)
 
 /** \} */
 
+/* ---------------------------------------------------------------------- */
+/** \name Default implementations of virtual functions
+ * \{ */
+
 bool AbstractView::listen(const wmNotifier & /*notifier*/) const
 {
   /* Nothing by default. */
   return false;
 }
 
+/** \} */
+
+/* ---------------------------------------------------------------------- */
+/** \name Renaming
+ * \{ */
+
+bool AbstractView::is_renaming() const
+{
+  return rename_buffer_ != nullptr;
+}
+
+bool AbstractView::begin_renaming()
+{
+  if (is_renaming()) {
+    return false;
+  }
+
+  rename_buffer_ = std::make_unique<decltype(rename_buffer_)::element_type>();
+  return true;
+}
+
+void AbstractView::end_renaming()
+{
+  BLI_assert(is_renaming());
+  rename_buffer_ = nullptr;
+}
+
+Span<char> AbstractView::get_rename_buffer() const
+{
+  return *rename_buffer_;
+}
+MutableSpan<char> AbstractView::get_rename_buffer()
+{
+  return *rename_buffer_;
+}
+
+/** \} */
+
 }  // namespace blender::ui
diff --git a/source/blender/editors/interface/tree_view.cc b/source/blender/editors/interface/tree_view.cc
index e892e7c272c..d29cf367e59 100644
--- a/source/blender/editors/interface/tree_view.cc
+++ b/source/blender/editors/interface/tree_view.cc
@@ -68,23 +68,9 @@ void AbstractTreeView::foreach_item(ItemIterFn iter_fn, IterOptions options) con
   foreach_item_recursive(iter_fn, options);
 }
 
-bool AbstractTreeView::is_renaming() const
-{
-  return rename_buffer_ != nullptr;
-}
-
 void AbstractTreeView::update_children_from_old(const AbstractView &old_view)
 {
-  /* TODO: Get rid of const cast. */
-  AbstractTreeView &old_tree_view = const_cast<AbstractTreeView &>(
-      dynamic_cast<const AbstractTreeView &>(old_view));
-
-  /* TODO: Move to AbstractView. */
-  /* Update own persistent data. */
-  /* Keep the rename buffer persistent while renaming! The rename button uses the buffer's
-   * pointer to identify itself over redraws. */
-  rename_buffer_ = std::move(old_tree_view.rename_buffer_);
-  old_tree_view.rename_buffer_ = nullptr;
+  const AbstractTreeView &old_tree_view = dynamic_cast<const AbstractTreeView &>(old_view);
 
   update_children_from_old_recursive(*this, old_tree_view);
 }
@@ -233,7 +219,7 @@ AbstractTreeViewItem *AbstractTreeViewItem::find_tree_item_from_rename_button(
     AbstractTreeViewItem *item = reinterpret_cast<AbstractTreeViewItem *>(tree_row_but->tree_item);
     const AbstractTreeView &tree_view = item->get_tree_view();
 
-    if (item->is_renaming() && (tree_view.rename_buffer_->data() == rename_but.poin)) {
+    if (item->is_renaming() && (tree_view.get_rename_buffer().data() == rename_but.poin)) {
       return item;
     }
   }
@@ -248,7 +234,7 @@ void AbstractTreeViewItem::rename_button_fn(bContext *UNUSED(C), void *arg, char
   BLI_assert(item);
 
   const AbstractTreeView &tree_view = item->get_tree_view();
-  item->rename(tree_view.rename_buffer_->data());
+  item->rename(tree_view.get_rename_buffer().data());
   item->end_renaming();
 }
 
@@ -270,9 +256,9 @@ void AbstractTreeViewItem::add_rename_button(uiLayout &row)
                                0,
                                UI_UNIT_X * 10,
                                UI_UNIT_Y,
-                               tree_view.rename_buffer_->data(),
+                               tree_view.get_rename_buffer().data(),
                                1.0f,
-                               tree_view.rename_buffer_->max_size(),
+                               tree_view.get_rename_buffer().size(),
                                0,
                                0,
                                "");
@@ -372,10 +358,11 @@ void AbstractTreeViewItem::begin_renaming()
     return;
   }
 
-  is_renaming_ = true;
+  if (tree_view.begin_renaming()) {
+    is_renaming_ = true;
+  }
 
-  tree_view.rename_buffer_ = std::make_unique<decltype(tree_view.rename_buffer_)::element_type>();
-  std::copy(std::begin(label_), std::end(label_), std::begin(*tree_view.rename_buffer_));
+  std::copy(std::begin(label_), std::end(label_), std::begin(tree_view.get_rename_buffer()));
 }
 
 void AbstractTreeViewItem::end_renaming()
@@ -387,7 +374,7 @@ void AbstractTreeViewItem::end_renaming()
   is_renaming_ = false;
 
   AbstractTreeView &tree_view = get_tree_view();
-  tree_view.rename_buffer_ = nullptr;
+  tree_view.end_renaming();
 }
 
 AbstractTreeView &AbstractTreeViewItem::get_tree_view() const