Android学习之Handler消息传递机制

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		final TextView txt=(TextView)findViewById(R.id.showTime);
		final Handler myHandler=new Handler()
		{
			@Override
			public void handleMessage(Message msg)
			{
				if(msg.what==0x12)
				{
					txt.setText("当前时间:"+new java.util.Date());
				}
			}
		};
		Button btn=(Button)findViewById(R.id.btn);
		btn.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				
				new Timer().schedule(new TimerTask() {
					
					@Override
					public void run() {
						// TODO Auto-generated method stub
						myHandler.sendEmptyMessage(0x12);
					}
				}, 0,1000);
			}
		});
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}