Use callable for `TreeItem` custom draw

Deprecating old functionality

doc/classes/TreeItem.xml

@@ -160,6 +160,13 @@
 				Returns the custom color of column [param column].
 			</description>
 		</method>
+		<method name="get_custom_draw_callback" qualifiers="const">
+			<return type="Callable" />
+			<param index="0" name="column" type="int" />
+			<description>
+				Returns the custom callback of column [param column].
+			</description>
+		</method>
 		<method name="get_custom_font" qualifiers="const">
 			<return type="Font" />
 			<param index="0" name="column" type="int" />
@@ -553,7 +560,7 @@
 				Sets the given column's custom color.
 			</description>
 		</method>
-		<method name="set_custom_draw">
+		<method name="set_custom_draw" is_deprecated="true">
 			<return type="void" />
 			<param index="0" name="column" type="int" />
 			<param index="1" name="object" type="Object" />
@@ -561,6 +568,16 @@
 			<description>
 				Sets the given column's custom draw callback to [param callback] method on [param object].
 				The [param callback] should accept two arguments: the [TreeItem] that is drawn and its position and size as a [Rect2].
+				[i]Deprecated.[/i] Use [method TreeItem.set_custom_draw_callback] instead.
+			</description>
+		</method>
+		<method name="set_custom_draw_callback">
+			<return type="void" />
+			<param index="0" name="column" type="int" />
+			<param index="1" name="callback" type="Callable" />
+			<description>
+				Sets the given column's custom draw callback. Use an empty [Callable] ([code skip-lint]Callable()[/code]) to clear the custom callback.
+				The [param callback] should accept two arguments: the [TreeItem] that is drawn and its position and size as a [Rect2].
 			</description>
 		</method>
 		<method name="set_custom_font">

editor/find_in_files.cpp

@@ -747,7 +747,7 @@ void FindInFilesPanel::_on_result_found(String fpath, int line_number, int begin
 	String start = vformat("%3s: ", line_number);
 
 	item->set_text(text_index, start + text);
-	item->set_custom_draw(text_index, this, "_draw_result_text");
+	item->set_custom_draw_callback(text_index, callable_mp(this, &FindInFilesPanel::draw_result_text));
 
 	Result r;
 	r.line_number = line_number;
@@ -988,7 +988,6 @@ void FindInFilesPanel::set_progress_visible(bool p_visible) {
 void FindInFilesPanel::_bind_methods() {
 	ClassDB::bind_method("_on_result_found", &FindInFilesPanel::_on_result_found);
 	ClassDB::bind_method("_on_finished", &FindInFilesPanel::_on_finished);
-	ClassDB::bind_method("_draw_result_text", &FindInFilesPanel::draw_result_text);
 
 	ADD_SIGNAL(MethodInfo(SIGNAL_RESULT_SELECTED,
 			PropertyInfo(Variant::STRING, "path"),

scene/gui/tree.cpp

@@ -584,16 +584,32 @@ Variant TreeItem::get_metadata(int p_column) const {
 	return cells[p_column].meta;
 }
 
+#ifndef DISABLE_DEPRECATED
 void TreeItem::set_custom_draw(int p_column, Object *p_object, const StringName &p_callback) {
+	WARN_DEPRECATED_MSG(R"*(The "set_custom_draw()" method is deprecated, use "set_custom_draw_callback()" instead.)*");
 	ERR_FAIL_INDEX(p_column, cells.size());
 	ERR_FAIL_NULL(p_object);
 
-	cells.write[p_column].custom_draw_obj = p_object->get_instance_id();
+	cells.write[p_column].custom_draw_callback = Callable(p_object, p_callback);
+
+	_changed_notify(p_column);
+}
+#endif // DISABLE_DEPRECATED
+
+void TreeItem::set_custom_draw_callback(int p_column, const Callable &p_callback) {
+	ERR_FAIL_INDEX(p_column, cells.size());
+
 	cells.write[p_column].custom_draw_callback = p_callback;
 
 	_changed_notify(p_column);
 }
 
+Callable TreeItem::get_custom_draw_callback(int p_column) const {
+	ERR_FAIL_INDEX_V(p_column, cells.size(), Callable());
+
+	return cells[p_column].custom_draw_callback;
+}
+
 void TreeItem::set_collapsed(bool p_collapsed) {
 	if (collapsed == p_collapsed || !tree) {
 		return;
@@ -1594,7 +1610,11 @@ void TreeItem::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_metadata", "column", "meta"), &TreeItem::set_metadata);
 	ClassDB::bind_method(D_METHOD("get_metadata", "column"), &TreeItem::get_metadata);
 
+#ifndef DISABLE_DEPRECATED
 	ClassDB::bind_method(D_METHOD("set_custom_draw", "column", "object", "callback"), &TreeItem::set_custom_draw);
+#endif // DISABLE_DEPRECATED
+	ClassDB::bind_method(D_METHOD("set_custom_draw_callback", "column", "callback"), &TreeItem::set_custom_draw_callback);
+	ClassDB::bind_method(D_METHOD("get_custom_draw_callback", "column"), &TreeItem::get_custom_draw_callback);
 
 	ClassDB::bind_method(D_METHOD("set_collapsed", "enable"), &TreeItem::set_collapsed);
 	ClassDB::bind_method(D_METHOD("is_collapsed"), &TreeItem::is_collapsed);
@@ -2317,10 +2337,15 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 
 				} break;
 				case TreeItem::CELL_MODE_CUSTOM: {
-					if (p_item->cells[i].custom_draw_obj.is_valid()) {
-						Object *cdo = ObjectDB::get_instance(p_item->cells[i].custom_draw_obj);
-						if (cdo) {
-							cdo->call(p_item->cells[i].custom_draw_callback, p_item, Rect2(item_rect));
+					if (p_item->cells[i].custom_draw_callback.is_valid()) {
+						Variant args[] = { p_item, Rect2(item_rect) };
+						const Variant *argptrs[] = { &args[0], &args[1] };
+
+						Callable::CallError ce;
+						Variant ret;
+						p_item->cells[i].custom_draw_callback.callp(argptrs, 2, ret, ce);
+						if (ce.error != Callable::CallError::CALL_OK) {
+							ERR_PRINT("Error calling custom draw method: " + Variant::get_callable_error_text(p_item->cells[i].custom_draw_callback, argptrs, 2, ce) + ".");
 						}
 					}
 

scene/gui/tree.h

@@ -99,8 +99,7 @@ private:
 		Variant meta;
 		String tooltip;
 
-		ObjectID custom_draw_obj;
-		StringName custom_draw_callback;
+		Callable custom_draw_callback;
 
 		struct Button {
 			int id = 0;
@@ -285,7 +284,11 @@ public:
 	void set_metadata(int p_column, const Variant &p_meta);
 	Variant get_metadata(int p_column) const;
 
+#ifndef DISABLE_DEPRECATED
 	void set_custom_draw(int p_column, Object *p_object, const StringName &p_callback);
+#endif // DISABLE_DEPRECATED
+	void set_custom_draw_callback(int p_column, const Callable &p_callback);
+	Callable get_custom_draw_callback(int p_column) const;
 
 	void set_collapsed(bool p_collapsed);
 	bool is_collapsed();