add dark mode setting

src/actions/index.ts

@@ -17,6 +17,7 @@ import {
 import { MpyAction } from './mpy';
 import { NotificationAction } from './notification';
 import { ServiceWorkerAction } from './service-worker';
+import { SettingsAction } from './settings';
 import { TerminalDataAction } from './terminal';
 
 /**
@@ -38,6 +39,7 @@ export type Action =
     | MpyAction
     | NotificationAction
     | ServiceWorkerAction
+    | SettingsAction
     | TerminalDataAction;
 
 /**

src/actions/settings.ts

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2021 The Pybricks Authors
+
+import { Action } from 'redux';
+
+/** Actions related to settings. */
+export enum SettingsActionType {
+    ToggleDarkMode = 'settings.action.toggleDarkMode',
+}
+
+/** Action to toggle dark mode setting. */
+export type SettingsToggleDarkModeAction = Action<SettingsActionType.ToggleDarkMode>;
+
+/** Toggles dark mode setting on or off. */
+export function toggleDarkMode(): SettingsToggleDarkModeAction {
+    return { type: SettingsActionType.ToggleDarkMode };
+}
+
+/** common type for all settings actions. */
+export type SettingsAction = SettingsToggleDarkModeAction;