随笔分类(157)

最近帮公司做flash，要求flash里播放视频，采用的是flash播放外部flv视频的方式。为了能够在播放的时候有顺利流畅的效果，所以事先把所要播放的flv文件全部先预加载，加载完毕后再开始播放。其部分主要action script类似如下，在flash里新建视频元件，然后用netstream控制flv的播放，其方法bytesLoaded、bytesTotal可用作计算预加载的进度统计，progressBar显示loading条。如果服务器不支持flv文件，将flv改为swf类型便可。

stop();
my_nc = new NetConnection();
my_nc.connect(null);
my_ns = new NetStream(my_nc);
Finance.attachVideo(my_ns);
my_ns.play("Finance.swf");

my_nc3 = new NetConnection();
my_nc3.connect(null);
my_ns3= new NetStream(my_nc3);
ns3.attachVideo(my_ns3);
my_ns3.play("3.swf");

  
   this.createTextField("loaded_txt", this.getNextHighestDepth(), 10, 10,
    160, 22);
    this.createEmptyMovieClip("progressBar_mc", this.getNextHighestDepth());
    progressBar_mc.createEmptyMovieClip("bar_mc",
    progressBar_mc.getNextHighestDepth());
    with (progressBar_mc.bar_mc) {
    beginFill(0xFF0000);
    moveTo(0, 0);
    lineTo(100, 0);
    lineTo(100, 10);
    lineTo(0, 10);
    lineTo(0, 0);
    endFill();
    _xscale = 0;
    }
    progressBar_mc.createEmptyMovieClip("stroke_mc",
    progressBar_mc.getNextHighestDepth());
    with (progressBar_mc.stroke_mc) {
    lineStyle(0, 0x000000);
    moveTo(0, 0);
    lineTo(100, 0);
    lineTo(100, 10);
    lineTo(0, 10);
    lineTo(0, 0);
    }
    var loaded_interval:Number = setInterval(checkBytesLoaded, 500,
    my_ns,my_ns3);
 
    function checkBytesLoaded(my_ns:NetStream) {
    var pctLoaded:Number = Math.round(my_ns.bytesLoaded / my_ns.bytesTotal
    * 100);
    loaded_txt.text = Math.round(my_ns.bytesLoaded / 1000 + my_ns3.bytesLoaded / 1000) + " of " +
    Math.round(my_ns.bytesTotal / 1000 + my_ns3.bytesTotal / 1000) + " KB loaded (" + pctLoaded +
    "%)";
    progressBar_mc.bar_mc._xscale = pctLoaded;
    if (pctLoaded>=100) {
  loaded_txt._visible=false;
  progressBar_mc._visible=false;
  clearInterval(loaded_interval);
  play();
    }else{
  stop();
  }
    }