Fix theme application in various editor dialogs

99% of the time we shouldn't rely on the signal, we
should use the notification instead. I left some comments
in places where I couldn't quickly improve the code.

(cherry picked from commit 01888ae7ab2d8989b6e25cb2edbe7b3d27cf4e4e)

editor/editor_about.cpp

@@ -39,29 +39,25 @@
 // The metadata key used to store and retrieve the version text to copy to the clipboard.
 const String EditorAbout::META_TEXT_TO_COPY = "text_to_copy";
 
-void EditorAbout::_theme_changed() {
-	const Ref<Font> font = get_theme_font(SNAME("source"), EditorStringName(EditorFonts));
-	const int font_size = get_theme_font_size(SNAME("source_size"), EditorStringName(EditorFonts));
-
-	_tpl_text->begin_bulk_theme_override();
-	_tpl_text->add_theme_font_override("normal_font", font);
-	_tpl_text->add_theme_font_size_override("normal_font_size", font_size);
-	_tpl_text->add_theme_constant_override("line_separation", 4 * EDSCALE);
-	_tpl_text->end_bulk_theme_override();
-
-	_license_text->begin_bulk_theme_override();
-	_license_text->add_theme_font_override("normal_font", font);
-	_license_text->add_theme_font_size_override("normal_font_size", font_size);
-	_license_text->add_theme_constant_override("line_separation", 4 * EDSCALE);
-	_license_text->end_bulk_theme_override();
-
-	_logo->set_texture(get_editor_theme_icon(SNAME("Logo")));
-}
-
 void EditorAbout::_notification(int p_what) {
 	switch (p_what) {
-		case NOTIFICATION_ENTER_TREE: {
-			_theme_changed();
+		case NOTIFICATION_THEME_CHANGED: {
+			const Ref<Font> font = get_theme_font(SNAME("source"), EditorStringName(EditorFonts));
+			const int font_size = get_theme_font_size(SNAME("source_size"), EditorStringName(EditorFonts));
+
+			_tpl_text->begin_bulk_theme_override();
+			_tpl_text->add_theme_font_override("normal_font", font);
+			_tpl_text->add_theme_font_size_override("normal_font_size", font_size);
+			_tpl_text->add_theme_constant_override("line_separation", 4 * EDSCALE);
+			_tpl_text->end_bulk_theme_override();
+
+			_license_text->begin_bulk_theme_override();
+			_license_text->add_theme_font_override("normal_font", font);
+			_license_text->add_theme_font_size_override("normal_font_size", font_size);
+			_license_text->add_theme_constant_override("line_separation", 4 * EDSCALE);
+			_license_text->end_bulk_theme_override();
+
+			_logo->set_texture(get_editor_theme_icon(SNAME("Logo")));
 		} break;
 	}
 }
@@ -128,12 +124,12 @@ EditorAbout::EditorAbout() {
 	set_hide_on_ok(true);
 
 	VBoxContainer *vbc = memnew(VBoxContainer);
-	vbc->connect("theme_changed", callable_mp(this, &EditorAbout::_theme_changed));
+	add_child(vbc);
+
 	HBoxContainer *hbc = memnew(HBoxContainer);
 	hbc->set_h_size_flags(Control::SIZE_EXPAND_FILL);
 	hbc->set_alignment(BoxContainer::ALIGNMENT_CENTER);
 	hbc->add_theme_constant_override("separation", 30 * EDSCALE);
-	add_child(vbc);
 	vbc->add_child(hbc);
 
 	_logo = memnew(TextureRect);

editor/editor_about.h

@@ -64,8 +64,6 @@ private:
 	RichTextLabel *_tpl_text = nullptr;
 	TextureRect *_logo = nullptr;
 
-	void _theme_changed();
-
 protected:
 	void _notification(int p_what);
 	static void _bind_methods();

editor/editor_command_palette.cpp

@@ -129,8 +129,8 @@ void EditorCommandPalette::_update_command_search(const String &search_text) {
 			section->set_text(0, item_name);
 			section->set_selectable(0, false);
 			section->set_selectable(1, false);
-			section->set_custom_bg_color(0, search_options->get_theme_color(SNAME("prop_subsection"), EditorStringName(Editor)));
-			section->set_custom_bg_color(1, search_options->get_theme_color(SNAME("prop_subsection"), EditorStringName(Editor)));
+			section->set_custom_bg_color(0, get_theme_color(SNAME("prop_subsection"), EditorStringName(Editor)));
+			section->set_custom_bg_color(1, get_theme_color(SNAME("prop_subsection"), EditorStringName(Editor)));
 
 			sections[section_name] = section;
 		}
@@ -164,6 +164,10 @@ void EditorCommandPalette::_notification(int p_what) {
 				was_showed = true;
 			}
 		} break;
+
+		case NOTIFICATION_THEME_CHANGED: {
+			command_search_box->set_right_icon(get_editor_theme_icon(SNAME("Search")));
+		} break;
 	}
 }
 
@@ -303,10 +307,6 @@ Ref<Shortcut> EditorCommandPalette::add_shortcut_command(const String &p_command
 	return p_shortcut;
 }
 
-void EditorCommandPalette::_theme_changed() {
-	command_search_box->set_right_icon(search_options->get_editor_theme_icon(SNAME("Search")));
-}
-
 void EditorCommandPalette::_save_history() const {
 	Dictionary command_history;
 
@@ -330,7 +330,6 @@ EditorCommandPalette::EditorCommandPalette() {
 	connect("confirmed", callable_mp(this, &EditorCommandPalette::_confirmed));
 
 	VBoxContainer *vbc = memnew(VBoxContainer);
-	vbc->connect("theme_changed", callable_mp(this, &EditorCommandPalette::_theme_changed));
 	add_child(vbc);
 
 	command_search_box = memnew(LineEdit);

editor/editor_command_palette.h

@@ -83,10 +83,9 @@ class EditorCommandPalette : public ConfirmationDialog {
 	float _score_path(const String &p_search, const String &p_path);
 	void _sbox_input(const Ref<InputEvent> &p_ie);
 	void _confirmed();
-	void _update_command_keys();
 	void _add_command(String p_command_name, String p_key_name, Callable p_binded_action, String p_shortcut_text = "None");
-	void _theme_changed();
 	void _save_history() const;
+
 	EditorCommandPalette();
 
 protected:

editor/editor_quick_open.cpp

@@ -250,23 +250,22 @@ void EditorQuickOpen::_notification(int p_what) {
 			}
 		} break;
 
+		case NOTIFICATION_THEME_CHANGED: {
+			search_box->set_right_icon(get_editor_theme_icon(SNAME("Search")));
+		} break;
+
 		case NOTIFICATION_EXIT_TREE: {
 			disconnect("confirmed", callable_mp(this, &EditorQuickOpen::_confirmed));
 		} break;
 	}
 }
 
-void EditorQuickOpen::_theme_changed() {
-	search_box->set_right_icon(search_options->get_editor_theme_icon(SNAME("Search")));
-}
-
 void EditorQuickOpen::_bind_methods() {
 	ADD_SIGNAL(MethodInfo("quick_open"));
 }
 
 EditorQuickOpen::EditorQuickOpen() {
 	VBoxContainer *vbc = memnew(VBoxContainer);
-	vbc->connect("theme_changed", callable_mp(this, &EditorQuickOpen::_theme_changed));
 	add_child(vbc);
 
 	search_box = memnew(LineEdit);

editor/editor_quick_open.h

@@ -72,8 +72,6 @@ class EditorQuickOpen : public ConfirmationDialog {
 	void _sbox_input(const Ref<InputEvent> &p_ie);
 	void _text_changed(const String &p_newtext);
 
-	void _theme_changed();
-
 protected:
 	void _notification(int p_what);
 	static void _bind_methods();

editor/export/project_export.cpp

@@ -90,11 +90,6 @@ ProjectExportTextureFormatError::ProjectExportTextureFormatError() {
 	fix_texture_format_button->connect("pressed", callable_mp(this, &ProjectExportTextureFormatError::_on_fix_texture_format_pressed));
 }
 
-void ProjectExportDialog::_theme_changed() {
-	duplicate_preset->set_icon(presets->get_editor_theme_icon(SNAME("Duplicate")));
-	delete_preset->set_icon(presets->get_editor_theme_icon(SNAME("Remove")));
-}
-
 void ProjectExportDialog::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_VISIBILITY_CHANGED: {
@@ -103,6 +98,11 @@ void ProjectExportDialog::_notification(int p_what) {
 			}
 		} break;
 
+		case NOTIFICATION_THEME_CHANGED: {
+			duplicate_preset->set_icon(presets->get_editor_theme_icon(SNAME("Duplicate")));
+			delete_preset->set_icon(presets->get_editor_theme_icon(SNAME("Remove")));
+		} break;
+
 		case NOTIFICATION_READY: {
 			duplicate_preset->set_icon(presets->get_editor_theme_icon(SNAME("Duplicate")));
 			delete_preset->set_icon(presets->get_editor_theme_icon(SNAME("Remove")));
@@ -1161,8 +1161,8 @@ ProjectExportDialog::ProjectExportDialog() {
 	set_clamp_to_embedder(true);
 
 	VBoxContainer *main_vb = memnew(VBoxContainer);
-	main_vb->connect("theme_changed", callable_mp(this, &ProjectExportDialog::_theme_changed));
 	add_child(main_vb);
+
 	HSplitContainer *hbox = memnew(HSplitContainer);
 	main_vb->add_child(hbox);
 	hbox->set_v_size_flags(Control::SIZE_EXPAND_FILL);

editor/export/project_export.h

@@ -188,7 +188,6 @@ class ProjectExportDialog : public ConfirmationDialog {
 	void _tab_changed(int);
 
 protected:
-	void _theme_changed();
 	void _notification(int p_what);
 	static void _bind_methods();
 

editor/plugins/path_3d_editor_plugin.cpp

@@ -713,6 +713,9 @@ void Path3DEditorPlugin::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_READY: {
+			// FIXME: This can trigger theme updates when the nodes that we want to update are not yet available.
+			// The toolbar should be extracted to a dedicated control and theme updates should be handled through
+			// the notification.
 			Node3DEditor::get_singleton()->connect("theme_changed", callable_mp(this, &Path3DEditorPlugin::_update_theme));
 		} break;
 	}

editor/plugins/tiles/tile_map_editor.cpp

@@ -2373,7 +2373,9 @@ TileMapEditorTilesPlugin::TileMapEditorTilesPlugin() {
 
 	// --- Bottom panel tiles ---
 	tiles_bottom_panel = memnew(VBoxContainer);
-	tiles_bottom_panel->connect("tree_entered", callable_mp(this, &TileMapEditorTilesPlugin::_update_theme));
+	// FIXME: This can trigger theme updates when the nodes that we want to update are not yet available.
+	// The toolbar should be extracted to a dedicated control and theme updates should be handled through
+	// the notification.
 	tiles_bottom_panel->connect("theme_changed", callable_mp(this, &TileMapEditorTilesPlugin::_update_theme));
 	tiles_bottom_panel->connect("visibility_changed", callable_mp(this, &TileMapEditorTilesPlugin::_stop_dragging));
 	tiles_bottom_panel->connect("visibility_changed", callable_mp(this, &TileMapEditorTilesPlugin::_tab_changed));
@@ -3536,7 +3538,9 @@ void TileMapEditorTerrainsPlugin::edit(ObjectID p_tile_map_id, int p_tile_map_la
 
 TileMapEditorTerrainsPlugin::TileMapEditorTerrainsPlugin() {
 	main_vbox_container = memnew(VBoxContainer);
-	main_vbox_container->connect("tree_entered", callable_mp(this, &TileMapEditorTerrainsPlugin::_update_theme));
+	// FIXME: This can trigger theme updates when the nodes that we want to update are not yet available.
+	// The toolbar should be extracted to a dedicated control and theme updates should be handled through
+	// the notification.
 	main_vbox_container->connect("theme_changed", callable_mp(this, &TileMapEditorTerrainsPlugin::_update_theme));
 	main_vbox_container->set_name(TTR("Terrains"));
 

editor/shader_create_dialog.cpp

@@ -48,8 +48,6 @@ enum ShaderType {
 void ShaderCreateDialog::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_ENTER_TREE: {
-			_update_theme();
-
 			String last_lang = EditorSettings::get_singleton()->get_project_metadata("shader_setup", "last_selected_language", "");
 			if (!last_lang.is_empty()) {
 				for (int i = 0; i < type_menu->get_item_count(); i++) {
@@ -68,28 +66,17 @@ void ShaderCreateDialog::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_THEME_CHANGED: {
-			_update_theme();
-		} break;
-	}
-}
-
-void ShaderCreateDialog::_update_theme() {
-	Ref<Texture2D> shader_icon = gc->get_editor_theme_icon(SNAME("Shader"));
-	if (shader_icon.is_valid()) {
-		type_menu->set_item_icon(0, shader_icon);
-	}
-
-	Ref<Texture2D> visual_shader_icon = gc->get_editor_theme_icon(SNAME("VisualShader"));
-	if (visual_shader_icon.is_valid()) {
-		type_menu->set_item_icon(1, visual_shader_icon);
-	}
+			static const char *shader_types[3] = { "Shader", "VisualShader", "TextFile" };
+			for (int i = 0; i < 3; i++) {
+				Ref<Texture2D> icon = get_editor_theme_icon(shader_types[i]);
+				if (icon.is_valid()) {
+					type_menu->set_item_icon(i, icon);
+				}
+			}
 
-	Ref<Texture2D> include_icon = gc->get_editor_theme_icon(SNAME("TextFile"));
-	if (include_icon.is_valid()) {
-		type_menu->set_item_icon(2, include_icon);
+			path_button->set_icon(get_editor_theme_icon(SNAME("Folder")));
+		} break;
 	}
-
-	path_button->set_icon(get_editor_theme_icon(SNAME("Folder")));
 }
 
 void ShaderCreateDialog::_update_language_info() {

editor/shader_create_dialog.h

@@ -101,7 +101,6 @@ class ShaderCreateDialog : public ConfirmationDialog {
 	void _update_dialog();
 
 protected:
-	void _update_theme();
 	void _notification(int p_what);
 	static void _bind_methods();