third_party/WebKit/LayoutTests/webaudio/resources/buffer-loader.js

   1 function BufferLoader(context, urlList, callback) {
   2     this.context = context;
   3     this.urlList = urlList;
   4     this.onload = callback;
   5     this.bufferList = new Array();
   6     this.loadCount = 0;
   7 }
   8
   9 BufferLoader.prototype.loadBuffer = function(url, index) {
  10     // Load buffer asynchronously
  11     var request = new XMLHttpRequest();
  12     request.open("GET", url, true);
  13     request.responseType = "arraybuffer";
  14
  15     var loader = this;
  16
  17     request.onload = function() {
  18         loader.context.decodeAudioData(
  19             request.response,
  20             function (decodedAudio) {
  21                 try {
  22                     loader.bufferList[index] = decodedAudio;
  23                     if (++loader.loadCount == loader.urlList.length)
  24                         loader.onload(loader.bufferList);
  25                 } catch(e) {
  26                     alert('BufferLoader: unable to load buffer' + index);
  27                 }
  28             },
  29             function () {
  30                 alert('error decoding file data: ' + url);
  31             });
  32     }
  33
  34     request.onerror = function() {
  35         alert('BufferLoader: XHR error');
  36     }
  37
  38     request.send();
  39 }
  40
  41 BufferLoader.prototype.load = function() {
  42     for (var i = 0; i < this.urlList.length; ++i)
  43         this.loadBuffer(this.urlList[i], i);
  44 }