text: Ext.define('Pandora.view.SongControls', {
      extend: 'Ext.Container',
      alias: 'widget.songcontrols',
      height: 70,
      //初始化
      //initComponent是在构造函数constructor中被调用的
      //该函数中必须调用 callParent()方法，不然调用者无法初始化这个对象
      //一般使用该函数进行初始化
      initComponent: function() {
          this.layout = {
              type: 'vbox',
              align: 'center',
              pack: 'center'
          };
          
          this.items = [{
              xtype: 'container',
              defaultType: 'button',
              height: 30,
              width: 300,
              layout: {
                  type: 'hbox',
                  align: 'center',
                  pack: 'center'
              },
              items: [{
                  text: 'Vote Down',
                  action: 'vote-down'
              }, {
                  text: 'Vote Up',
                  action: 'vote-up'
              }, {
                  text: 'Pause',
                  action: 'pause'
              }, {
                  text: 'Skip',
                  action: 'skip'
              }]
          }, {
              width: 300,
              xtype: 'container',
              layout: {
                  type: 'hbox',
                  align: 'center'
              },
              items: [{
                  xtype: 'component',
                  html: '2:00'
              }, {
                  xtype: 'progressbar',
                  value: 0.5,
                  flex: 1           
              }, {
                  xtype: 'component',
                  html: '4:00'
              }]
          }];
          
          this.callParent();
      }
  });