MD Settings: animation interface

chrome/browser/resources/settings/animation/transition.js

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+/**
+ * @fileoverview
+ * Transitions are cancellable asynchronous state changes. A transition may
+ * compose web animations and other Transitions to manage a set of animations.
+ * Similar to Promises, they can initiate tasks after completion or
+ * cancellation.
+ */
+cr.define('settings.animation', function() {
+  'use strict';
+
+  /**
+   * Base class for modular implementations of asynchronous transitions using
+   * web animations.
+   * @constructor
+   */
+  function Transition() {}
+
+  Transition.prototype = {
+    /**
+     * Starts the transition, including scheduling any animations.
+     * @return {!Promise} Convenient reference to |finished| for chaining.
+     */
+    play: function() {},

[Dan Beam, 2016/07/01 00:33:24]

shouldn't this also be assertNotReached() or something?

[michaelpg, 2016/07/01 20:21:46]

Done.

+
+    /**
+     * If the transition is still playing, immediately finishes it and resolves
+     * |finished|.
+     */
+    finish: assertNotReached,
+
+    /**
+     * If the transition is still playing, immediately cancels it and rejects
+     * |finished|.
+     */
+    cancel: assertNotReached,
+
+    /**
+     * Resolved or rejected when the transition is finished or canceled.
+     * @type {?Promise}
+     */
+    finished: null,
+  };
+
+  return {
+    Transition: Transition,
+  };
+});