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, 17 insertions, 55 deletions

diff --git a/source/blender/editors/interface/interface.cc b/source/blender/editors/interface/interface.cc
index c0df193de87..2f9e69137ed 100644
--- a/source/blender/editors/interface/interface.cc
+++ b/source/blender/editors/interface/interface.cc
@@ -769,20 +769,11 @@ static bool ui_but_equals_old(const uiBut *but, const uiBut *oldbut)
     return false;
   }
 
-  if ((but->type == UI_BTYPE_TREEROW) && (oldbut->type == UI_BTYPE_TREEROW)) {
-    uiButTreeRow *but_treerow = (uiButTreeRow *)but;
-    uiButTreeRow *oldbut_treerow = (uiButTreeRow *)oldbut;
-    if (!but_treerow->tree_item || !oldbut_treerow->tree_item ||
-        !UI_tree_view_item_matches(but_treerow->tree_item, oldbut_treerow->tree_item)) {
-      return false;
-    }
-  }
-
-  if ((but->type == UI_BTYPE_GRID_TILE) && (oldbut->type == UI_BTYPE_GRID_TILE)) {
-    uiButGridTile *but_gridtile = (uiButGridTile *)but;
-    uiButGridTile *oldbut_gridtile = (uiButGridTile *)oldbut;
-    if (!but_gridtile->view_item || !oldbut_gridtile->view_item ||
-        !UI_grid_view_item_matches(but_gridtile->view_item, oldbut_gridtile->view_item)) {
+  if ((but->type == UI_BTYPE_VIEW_ITEM) && (oldbut->type == UI_BTYPE_VIEW_ITEM)) {
+    uiButViewItem *but_item = (uiButViewItem *)but;
+    uiButViewItem *oldbut_item = (uiButViewItem *)oldbut;
+    if (!but_item->view_item || !oldbut_item->view_item ||
+        !UI_view_item_matches(but_item->view_item, oldbut_item->view_item)) {
       return false;
     }
   }
@@ -907,16 +898,10 @@ static void ui_but_update_old_active_from_new(uiBut *oldbut, uiBut *but)
       progress_oldbut->progress = progress_but->progress;
       break;
     }
-    case UI_BTYPE_TREEROW: {
-      uiButTreeRow *treerow_oldbut = (uiButTreeRow *)oldbut;
-      uiButTreeRow *treerow_newbut = (uiButTreeRow *)but;
-      SWAP(uiTreeViewItemHandle *, treerow_newbut->tree_item, treerow_oldbut->tree_item);
-      break;
-    }
-    case UI_BTYPE_GRID_TILE: {
-      uiButGridTile *gridtile_oldbut = (uiButGridTile *)oldbut;
-      uiButGridTile *gridtile_newbut = (uiButGridTile *)but;
-      SWAP(uiGridViewItemHandle *, gridtile_newbut->view_item, gridtile_oldbut->view_item);
+    case UI_BTYPE_VIEW_ITEM: {
+      uiButViewItem *view_item_oldbut = (uiButViewItem *)oldbut;
+      uiButViewItem *view_item_newbut = (uiButViewItem *)but;
+      SWAP(uiViewItemHandle *, view_item_newbut->view_item, view_item_oldbut->view_item);
       break;
     }
     default:
@@ -1013,7 +998,7 @@ static bool ui_but_update_from_old_block(const bContext *C,
 
     /* Stupid special case: The active button may be inside (as in, overlapped on top) a view-item
      * button which we also want to keep highlighted then. */
-    if (ui_but_is_view_item(but)) {
+    if (but->type == UI_BTYPE_VIEW_ITEM) {
       flag_copy |= UI_ACTIVE;
     }
 
@@ -2245,21 +2230,12 @@ int ui_but_is_pushed_ex(uiBut *but, double *value)
           }
         }
         break;
-      case UI_BTYPE_TREEROW: {
-        uiButTreeRow *tree_row_but = (uiButTreeRow *)but;
-
-        is_push = -1;
-        if (tree_row_but->tree_item) {
-          is_push = UI_tree_view_item_is_active(tree_row_but->tree_item);
-        }
-        break;
-      }
-      case UI_BTYPE_GRID_TILE: {
-        uiButGridTile *grid_tile_but = (uiButGridTile *)but;
+      case UI_BTYPE_VIEW_ITEM: {
+        const uiButViewItem *view_item_but = (const uiButViewItem *)but;
 
         is_push = -1;
-        if (grid_tile_but->view_item) {
-          is_push = UI_grid_view_item_is_active(grid_tile_but->view_item);
+        if (view_item_but->view_item) {
+          is_push = UI_view_item_is_active(view_item_but->view_item);
         }
         break;
       }
@@ -4011,17 +3987,13 @@ static void ui_but_alloc_info(const eButType type,
       alloc_size = sizeof(uiButCurveProfile);
       alloc_str = "uiButCurveProfile";
       break;
-    case UI_BTYPE_TREEROW:
-      alloc_size = sizeof(uiButTreeRow);
-      alloc_str = "uiButTreeRow";
-      break;
     case UI_BTYPE_HOTKEY_EVENT:
       alloc_size = sizeof(uiButHotkeyEvent);
       alloc_str = "uiButHotkeyEvent";
       break;
-    case UI_BTYPE_GRID_TILE:
-      alloc_size = sizeof(uiButGridTile);
-      alloc_str = "uiButGridTile";
+    case UI_BTYPE_VIEW_ITEM:
+      alloc_size = sizeof(uiButViewItem);
+      alloc_str = "uiButViewItem";
       break;
     default:
       alloc_size = sizeof(uiBut);
@@ -4214,7 +4186,6 @@ static uiBut *ui_def_but(uiBlock *block,
                 UI_BTYPE_BLOCK,
                 UI_BTYPE_BUT_MENU,
                 UI_BTYPE_SEARCH_MENU,
-                UI_BTYPE_TREEROW,
                 UI_BTYPE_POPOVER)) {
     but->drawflag |= (UI_BUT_TEXT_LEFT | UI_BUT_ICON_LEFT);
   }
@@ -6469,15 +6440,6 @@ uiBut *uiDefSearchButO_ptr(uiBlock *block,
   return but;
 }
 
-void UI_but_treerow_indentation_set(uiBut *but, int indentation)
-{
-  uiButTreeRow *but_row = (uiButTreeRow *)but;
-  BLI_assert(but->type == UI_BTYPE_TREEROW);
-
-  but_row->indentation = indentation;
-  BLI_assert(indentation >= 0);
-}
-
 void UI_but_hint_drawstr_set(uiBut *but, const char *string)
 {
   ui_but_add_shortcut(but, string, false);