android 广播

Handler handler = new Handler() { 
  @Override     
  public void handleMessage(Message msg) {    
   if (msg.what == 1) {        
    int index= msg.getData().getInt("index");  
    if(index!=0){    
     //显示进度         
     }        
    if(index>=100){  
     if(当前是非主Activity){ 
      //隐藏进度，弹出下载完成提示         
      }else{ 
       //给主Activity发送一个广播      
       Intent intent = new Intent("android.intent.action.MAIN");    
       sendBroadcast(intent);  
       }    
     }         
    }      
   }};
     }
    }
    }
   }
  }
 }

  同时，在主Activity中定义一个广播接收器，并处理
  Java代码

  BroadcastReceiver mReceiver=new BroadcastReceiver(){
   public void onReceive(Context context, Intent intent) {
    //刷新主Activity界面 
    init();
    }};
    IntentFilter intentFilter = new IntentFilter("android.intent.action.MAIN");
    registerReceiver(mReceiver, intentFilter);
  }