java文件
package com.luck.clock;
import android.os.Bundle;
import android.os.SystemClock;
import
android.app.Activity;
import android.view.Menu;
import
android.view.View;
import android.view.View.OnClickListener;
import
android.widget.Button;
import android.widget.Chronometer;
import
android.widget.Chronometer.OnChronometerTickListener;
public class Clock extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_clock);
final
Chronometer ch=(Chronometer)findViewById(R.id.ceshi);
Button
start=(Button)findViewById(R.id.start);
start.setOnClickListener(new
OnClickListener() {
@Override
public void onClick(View arg0)
{
// TODO Auto-generated method stub
//设置开始时间
获得系统实时时间
ch.setBase(SystemClock.elapsedRealtime());
//
开始计时
ch.start();
}
});
ch.setOnChronometerTickListener(new
OnChronometerTickListener() {
@Override
public void
onChronometerTick(Chronometer arg0) {
//
20s后停止计时
if(SystemClock.elapsedRealtime()-ch.getBase()>20*1000){
ch.stop();
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
//
Inflate the menu; this adds items to the action bar if it is
present.
getMenuInflater().inflate(R.menu.clock, menu);
return
true;
}
}
布局:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".Clock" >
<Chronometer
android:id="@+id/ceshi"
android:layout_width="100dp"
android:layout_height="50dp"
android:text="@string/ceshi"
/>
<Button
android:id="@+id/start"
android:layout_width="100dp"
android:layout_height="50dp"
android:text="@string/start"
android:textColor="#000000"
android:layout_below="@id/ceshi"
/>
<AnalogClock
android:id="@+id/ac"
android:layout_below="@id/start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
<DigitalClock
android:layout_below="@id/ac"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="14pt"
/>
</RelativeLayout>
原文:http://www.cnblogs.com/startPage/p/3586383.html