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