Source: ui/rewind_button.js

  1. /*! @license
  2.  * Shaka Player
  3.  * Copyright 2016 Google LLC
  4.  * SPDX-License-Identifier: Apache-2.0
  5.  */
  8. goog.provide('shaka.ui.RewindButton');
  10. goog.require('shaka.ui.Controls');
  11. goog.require('shaka.ui.Element');
  12. goog.require('shaka.ui.Enums');
  13. goog.require('shaka.ui.Locales');
  14. goog.require('shaka.ui.Localization');
  15. goog.require('shaka.util.Dom');
  18. /**
  19.  * @extends {shaka.ui.Element}
  20.  * @final
  21.  * @export
  22.  */
  23. shaka.ui.RewindButton = class extends shaka.ui.Element {
  24.   /**
  25.    * @param {!HTMLElement} parent
  26.    * @param {!shaka.ui.Controls} controls
  27.    */
  28.   constructor(parent, controls) {
  29.     super(parent, controls);
  31.     /** @private {!HTMLButtonElement} */
  32.     this.button_ = shaka.util.Dom.createButton();
  33.     this.button_.classList.add('material-icons-round');
  34.     this.button_.classList.add('shaka-rewind-button');
  35.     this.button_.textContent =
  36.       shaka.ui.Enums.MaterialDesignIcons.REWIND;
  37.     this.parent.appendChild(this.button_);
  38.     this.updateAriaLabel_();
  40.     this.eventManager.listen(
  41.         this.localization, shaka.ui.Localization.LOCALE_UPDATED, () => {
  42.           this.updateAriaLabel_();
  43.         });
  45.     this.eventManager.listen(
  46.         this.localization, shaka.ui.Localization.LOCALE_CHANGED, () => {
  47.           this.updateAriaLabel_();
  48.         });
  50.     this.eventManager.listen(this.button_, 'click', () => {
  51.       this.rewind_();
  52.     });
  53.   }
  55.   /**
  56.    * @private
  57.    */
  58.   updateAriaLabel_() {
  59.     this.button_.ariaLabel =
  60.         this.localization.resolve(shaka.ui.Locales.Ids.REWIND);
  61.   }
  63.   /**
  64.    * Cycles trick play rate between -1, -2, -4, and -8.
  65.    * @private
  66.    */
  67.   rewind_() {
  68.     if (!this.video.duration) {
  69.       return;
  70.     }
  72.     const trickPlayRate = this.player.getPlaybackRate();
  73.     // Every time the button is clicked, the rate is multiplied by 2,
  74.     // unless the rate is at it's slowest (-8), in which case it is
  75.     // dropped back to 1.
  76.     const newRate = (trickPlayRate > 0 || trickPlayRate < -4) ?
  77.         -1 : trickPlayRate * 2;
  78.     this.player.trickPlay(newRate);
  79.   }
  80. };
  83. /**
  84.  * @implements {shaka.extern.IUIElement.Factory}
  85.  * @final
  86.  */
  87. shaka.ui.RewindButton.Factory = class {
  88.   /** @override */
  89.   create(rootElement, controls) {
  90.     return new shaka.ui.RewindButton(rootElement, controls);
  91.   }
  92. };
  94. shaka.ui.Controls.registerElement(
  95.     'rewind', new shaka.ui.RewindButton.Factory());