Android开发八：多线程异步使用

public class DetailActivity extends Activity {

	ProgressBar bar;
		
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.detail);
		
		bar =(ProgressBar)findViewById(R.id.proBar);//风火轮
		
		/**
		 * VISIBLE:0  意思是可见的

		   INVISIBILITY:4 意思是不可见的，但还占着原来的空间

		   GONE:8  意思是不可见的，不占用原来的布局空间
		 * **/
		bar.setVisibility(0);
		// 创建一个线程
		HttpThread thread = new HttpThread(handler);
		// 开始新线程
		thread.start();
	}
	
	// 捕获消息队列
	Handler handler = new Handler() {
		 
		public void handleMessage(Message m) {
			bar.setVisibility(8);//隐藏"风火轮"
			switch(m.what)
			{
				case 1:
					//.....
					break;
				case 2:
					break;	
				case 3:
					break;
			}
		}
	};
	 // 线程类
	class HttpThread extends Thread {
		
		private Handler handle = null;

		// 构造函数
		public HttpThread(Handler hander) {
			handle = hander;
		}

		//启动线程
		public void doStart() {
			//提示信息...
			this.start();
		}

		//运行线程
		@Override
		public void run() {
			// TODO Auto-generated method stub
			super.run(); 
			try {
				dosomething();//做你应该做的....
			}catch (Exception ex) {
				ex.printStackTrace();
				
				//构造消息
				Message message = new Message();
				message.what =3;
				message.obj = ex.getMessage();//传递数据
				handle.sendMessage(message);
				
			} finally {

			}
		}	
	}
}