- 1 :
/** - 2 :
* @file track-list.js - 3 :
*/ - 4 :
import EventTarget from '../event-target'; - 5 :
import {isEvented} from '../mixins/evented'; - 6 :
- 7 :
/** - 8 :
* @typedef { import('./track').default } Track - 9 :
*/ - 10 :
- 11 :
/** - 12 :
* Common functionaliy between {@link TextTrackList}, {@link AudioTrackList}, and - 13 :
* {@link VideoTrackList} - 14 :
* - 15 :
* @extends EventTarget - 16 :
*/ - 17 :
class TrackList extends EventTarget { - 18 :
/** - 19 :
* Create an instance of this class - 20 :
* - 21 :
* @param {Track[]} tracks - 22 :
* A list of tracks to initialize the list with. - 23 :
* - 24 :
* @abstract - 25 :
*/ - 26 :
constructor(tracks = []) { - 27 :
super(); - 28 :
- 29 :
this.tracks_ = []; - 30 :
- 31 :
/** - 32 :
* @memberof TrackList - 33 :
* @member {number} length - 34 :
* The current number of `Track`s in the this Trackist. - 35 :
* @instance - 36 :
*/ - 37 :
Object.defineProperty(this, 'length', { - 38 :
get() { - 39 :
return this.tracks_.length; - 40 :
} - 41 :
}); - 42 :
- 43 :
for (let i = 0; i < tracks.length; i++) { - 44 :
this.addTrack(tracks[i]); - 45 :
} - 46 :
} - 47 :
- 48 :
/** - 49 :
* Add a {@link Track} to the `TrackList` - 50 :
* - 51 :
* @param {Track} track - 52 :
* The audio, video, or text track to add to the list. - 53 :
* - 54 :
* @fires TrackList#addtrack - 55 :
*/ - 56 :
addTrack(track) { - 57 :
const index = this.tracks_.length; - 58 :
- 59 :
if (!('' + index in this)) { - 60 :
Object.defineProperty(this, index, { - 61 :
get() { - 62 :
return this.tracks_[index]; - 63 :
} - 64 :
}); - 65 :
} - 66 :
- 67 :
// Do not add duplicate tracks - 68 :
if (this.tracks_.indexOf(track) === -1) { - 69 :
this.tracks_.push(track); - 70 :
/** - 71 :
* Triggered when a track is added to a track list. - 72 :
* - 73 :
* @event TrackList#addtrack - 74 :
* @type {Event} - 75 :
* @property {Track} track - 76 :
* A reference to track that was added. - 77 :
*/ - 78 :
this.trigger({ - 79 :
track, - 80 :
type: 'addtrack', - 81 :
target: this - 82 :
}); - 83 :
} - 84 :
- 85 :
/** - 86 :
* Triggered when a track label is changed. - 87 :
* - 88 :
* @event TrackList#addtrack - 89 :
* @type {Event} - 90 :
* @property {Track} track - 91 :
* A reference to track that was added. - 92 :
*/ - 93 :
track.labelchange_ = () => { - 94 :
this.trigger({ - 95 :
track, - 96 :
type: 'labelchange', - 97 :
target: this - 98 :
}); - 99 :
}; - 100 :
- 101 :
if (isEvented(track)) { - 102 :
track.addEventListener('labelchange', track.labelchange_); - 103 :
} - 104 :
} - 105 :
- 106 :
/** - 107 :
* Remove a {@link Track} from the `TrackList` - 108 :
* - 109 :
* @param {Track} rtrack - 110 :
* The audio, video, or text track to remove from the list. - 111 :
* - 112 :
* @fires TrackList#removetrack - 113 :
*/ - 114 :
removeTrack(rtrack) { - 115 :
let track; - 116 :
- 117 :
for (let i = 0, l = this.length; i < l; i++) { - 118 :
if (this[i] === rtrack) { - 119 :
track = this[i]; - 120 :
if (track.off) { - 121 :
track.off(); - 122 :
} - 123 :
- 124 :
this.tracks_.splice(i, 1); - 125 :
- 126 :
break; - 127 :
} - 128 :
} - 129 :
- 130 :
if (!track) { - 131 :
return; - 132 :
} - 133 :
- 134 :
/** - 135 :
* Triggered when a track is removed from track list. - 136 :
* - 137 :
* @event TrackList#removetrack - 138 :
* @type {Event} - 139 :
* @property {Track} track - 140 :
* A reference to track that was removed. - 141 :
*/ - 142 :
this.trigger({ - 143 :
track, - 144 :
type: 'removetrack', - 145 :
target: this - 146 :
}); - 147 :
} - 148 :
- 149 :
/** - 150 :
* Get a Track from the TrackList by a tracks id - 151 :
* - 152 :
* @param {string} id - the id of the track to get - 153 :
* @method getTrackById - 154 :
* @return {Track} - 155 :
* @private - 156 :
*/ - 157 :
getTrackById(id) { - 158 :
let result = null; - 159 :
- 160 :
for (let i = 0, l = this.length; i < l; i++) { - 161 :
const track = this[i]; - 162 :
- 163 :
if (track.id === id) { - 164 :
result = track; - 165 :
break; - 166 :
} - 167 :
} - 168 :
- 169 :
return result; - 170 :
} - 171 :
} - 172 :
- 173 :
/** - 174 :
* Triggered when a different track is selected/enabled. - 175 :
* - 176 :
* @event TrackList#change - 177 :
* @type {Event} - 178 :
*/ - 179 :
- 180 :
/** - 181 :
* Events that can be called with on + eventName. See {@link EventHandler}. - 182 :
* - 183 :
* @property {Object} TrackList#allowedEvents_ - 184 :
* @private - 185 :
*/ - 186 :
TrackList.prototype.allowedEvents_ = { - 187 :
change: 'change', - 188 :
addtrack: 'addtrack', - 189 :
removetrack: 'removetrack', - 190 :
labelchange: 'labelchange' - 191 :
}; - 192 :
- 193 :
// emulate attribute EventHandler support to allow for feature detection - 194 :
for (const event in TrackList.prototype.allowedEvents_) { - 195 :
TrackList.prototype['on' + event] = null; - 196 :
} - 197 :
- 198 :
export default TrackList;