UI: Port view item features to base class, merge view item button types

No user visible changes expected.

Merges the tree row and grid tile button types, which were mostly doing
the same things. The idea is that there is a button type for
highlighting, as well as supporting general view item features (e.g.
renaming, drag/drop, etc.). So instead there is a view item button type
now. Also ports view item features like renaming, custom context menus,
drag controllers and drop controllers to `ui::AbstractViewItem` (the new
base class for all view items).

This should be quite an improvement because:
- Merges code that was duplicated over view items.
- Mentioned features (renaming, drag & drop, ...) are much easier to
  implement in new view types now. Most of it comes "for free".
- Further features will immediately become availalbe to all views (e.g.
  selection).
- Simplifies APIs, there don't have to be functions for individual view
  item types anymore.
- View item classes are split and thus less overwhelming visually.
- View item buttons now share all code (drawing, handling, etc.)
- We're soon running out of available button types, this commit merges
  two into one.

I was hoping I could do this in multiple smaller commits, but things
were quite intertwined so that would've taken quite some effort.

1 files changed, 31 insertions, 33 deletions

diff --git a/source/blender/editors/interface/interface_ops.c b/source/blender/editors/interface/interface_ops.c
index aafb56119ae..7a51ed23677 100644
--- a/source/blender/editors/interface/interface_ops.c
+++ b/source/blender/editors/interface/interface_ops.c
@@ -2054,40 +2054,39 @@ static void UI_OT_list_start_filter(wmOperatorType *ot)
 /** \name UI Tree-View Drop Operator
  * \{ */
 
-static bool ui_tree_view_drop_poll(bContext *C)
+static bool ui_view_drop_poll(bContext *C)
 {
   const wmWindow *win = CTX_wm_window(C);
   const ARegion *region = CTX_wm_region(C);
-  const uiTreeViewItemHandle *hovered_tree_item = UI_block_tree_view_find_item_at(
-      region, win->eventstate->xy);
+  const uiViewItemHandle *hovered_item = UI_block_view_find_item_at(region, win->eventstate->xy);
 
-  return hovered_tree_item != NULL;
+  return hovered_item != NULL;
 }
 
-static int ui_tree_view_drop_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
+static int ui_view_drop_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *event)
 {
   if (event->custom != EVT_DATA_DRAGDROP) {
     return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
   }
 
   const ARegion *region = CTX_wm_region(C);
-  uiTreeViewItemHandle *hovered_tree_item = UI_block_tree_view_find_item_at(region, event->xy);
+  uiViewItemHandle *hovered_item = UI_block_view_find_item_at(region, event->xy);
 
-  if (!UI_tree_view_item_drop_handle(C, hovered_tree_item, event->customdata)) {
+  if (!UI_view_item_drop_handle(C, hovered_item, event->customdata)) {
     return OPERATOR_CANCELLED | OPERATOR_PASS_THROUGH;
   }
 
   return OPERATOR_FINISHED;
 }
 
-static void UI_OT_tree_view_drop(wmOperatorType *ot)
+static void UI_OT_view_drop(wmOperatorType *ot)
 {
-  ot->name = "Tree View drop";
-  ot->idname = "UI_OT_tree_view_drop";
-  ot->description = "Drag and drop items onto a tree item";
+  ot->name = "View drop";
+  ot->idname = "UI_OT_view_drop";
+  ot->description = "Drag and drop items onto a data-set item";
 
-  ot->invoke = ui_tree_view_drop_invoke;
-  ot->poll = ui_tree_view_drop_poll;
+  ot->invoke = ui_view_drop_invoke;
+  ot->poll = ui_view_drop_poll;
 
   ot->flag = OPTYPE_INTERNAL;
 }
@@ -2095,43 +2094,42 @@ static void UI_OT_tree_view_drop(wmOperatorType *ot)
 /** \} */
 
 /* -------------------------------------------------------------------- */
-/** \name UI Tree-View Item Rename Operator
+/** \name UI View Item Rename Operator
  *
- * General purpose renaming operator for tree-views. Thanks to this, to add a rename button to
- * context menus for example, tree-view API users don't have to implement their own renaming
- * operators with the same logic as they already have for their #ui::AbstractTreeViewItem::rename()
- * override.
+ * General purpose renaming operator for views. Thanks to this, to add a rename button to context
+ * menus for example, view API users don't have to implement their own renaming operators with the
+ * same logic as they already have for their #ui::AbstractViewItem::rename() override.
  *
  * \{ */
 
-static bool ui_tree_view_item_rename_poll(bContext *C)
+static bool ui_view_item_rename_poll(bContext *C)
 {
   const ARegion *region = CTX_wm_region(C);
-  const uiTreeViewItemHandle *active_item = UI_block_tree_view_find_active_item(region);
-  return active_item != NULL && UI_tree_view_item_can_rename(active_item);
+  const uiViewItemHandle *active_item = UI_block_view_find_active_item(region);
+  return active_item != NULL && UI_view_item_can_rename(active_item);
 }
 
-static int ui_tree_view_item_rename_exec(bContext *C, wmOperator *UNUSED(op))
+static int ui_view_item_rename_exec(bContext *C, wmOperator *UNUSED(op))
 {
   ARegion *region = CTX_wm_region(C);
-  uiTreeViewItemHandle *active_item = UI_block_tree_view_find_active_item(region);
+  uiViewItemHandle *active_item = UI_block_view_find_active_item(region);
 
-  UI_tree_view_item_begin_rename(active_item);
+  UI_view_item_begin_rename(active_item);
   ED_region_tag_redraw(region);
 
   return OPERATOR_FINISHED;
 }
 
-static void UI_OT_tree_view_item_rename(wmOperatorType *ot)
+static void UI_OT_view_item_rename(wmOperatorType *ot)
 {
-  ot->name = "Rename Tree-View Item";
-  ot->idname = "UI_OT_tree_view_item_rename";
-  ot->description = "Rename the active item in the tree";
+  ot->name = "Rename View Item";
+  ot->idname = "UI_OT_view_item_rename";
+  ot->description = "Rename the active item in the data-set view";
 
-  ot->exec = ui_tree_view_item_rename_exec;
-  ot->poll = ui_tree_view_item_rename_poll;
+  ot->exec = ui_view_item_rename_exec;
+  ot->poll = ui_view_item_rename_poll;
   /* Could get a custom tooltip via the `get_description()` callback and another overridable
-   * function of the tree-view. */
+   * function of the view. */
 
   ot->flag = OPTYPE_INTERNAL;
 }
@@ -2235,8 +2233,8 @@ void ED_operatortypes_ui(void)
 
   WM_operatortype_append(UI_OT_list_start_filter);
 
-  WM_operatortype_append(UI_OT_tree_view_drop);
-  WM_operatortype_append(UI_OT_tree_view_item_rename);
+  WM_operatortype_append(UI_OT_view_drop);
+  WM_operatortype_append(UI_OT_view_item_rename);
 
   /* external */
   WM_operatortype_append(UI_OT_eyedropper_color);