安卓--子線程和主線程之間的交互實例（時鐘）

.xml代碼如下：

package org.lxh.demo;

import java.util.Date;
import java.text.SimpleDateFormat;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.TextView;

public class Hello extends Activity {
	private TextView info = null;
	private static final int SET = 1;
	private Handler handler = new Handler() {

		@Override
		public void handleMessage(Message msg) {
			switch (msg.what) {
			case SET:
				Hello.this.info.setText("當前時間為：" + msg.obj.toString());
				break;
			}
		}

	};

	private class ClockThread implements Runnable {//顯示時間的線程類

		public void run() {
			while (true) {
				try {
					Message msg = Hello.this.handler.obtainMessage(Hello.SET,
							new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
									.format(new Date()));
					Hello.this.handler.sendMessage(msg);
					Thread.sleep(1000);
				} catch (Exception e) {
				}
			}

		}

	}

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState); // 生命周期方法
		super.setContentView(R.layout.main); // 設置要使用的布局管理器
		this.info = (TextView) super.findViewById(R.id.info);
		new Thread(new ClockThread()).start();//啟動線程

	}

}