安卓学习-界面-ui-AnalogClock、DigitalClock和Chronometer

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <AnalogClock
        android:id="@+id/analogClock1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" 
        android:dial="@drawable/b"

        />

     <DigitalClock
         android:layout_width="wrap_content"
         android:layout_height="match_parent" />

</LinearLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Chronometer
        android:id="@+id/chronometer1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Chronometer" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开始" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />
    
</LinearLayout>

public class MainActivity extends Activity {

    Chronometer chronometer1;
    Button button1;
    
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    
        chronometer1=(Chronometer)findViewById(R.id.chronometer1);
        //设置格式
        chronometer1.setFormat("计时器：%S");
        
        chronometer1.setOnChronometerTickListener(new OnChronometerTickListener() {

            public void onChronometerTick(Chronometer ch) {
                Message msg=new Message();
                Bundle b=new Bundle();
                //当前时间-开始计时的时间=实际计时了多少时间
                b.putString("time",(SystemClock.elapsedRealtime()- ch.getBase())/1000+"");
                msg.what=1111;
                msg.setData(b);
                handler.sendMessage(msg);
                if((SystemClock.elapsedRealtime()- ch.getBase())/1000>=5){
                    Toast.makeText(getApplicationContext(), "时间到了",Toast.LENGTH_SHORT).show();
                    ch.stop();
                }
                
            }
        });
        
        Button button1=(Button)findViewById(R.id.button1);
        button1.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v) {
                //计时开始
                chronometer1.start();
                
            }
        });
        
    }
    
    Handler handler=new Handler(){
        @Override
        public void handleMessage(Message msg) {
            if(msg.what==1111){
                TextView textView1=(TextView)findViewById(R.id.textView1);
                String time="通过message获取的时间："+msg.getData().getString("time");
                textView1.setText(time);
            }
        }
    };
    
    
}