今天和大家讲一下怎么实现秒表这个功能Chronometer。很多地方都要用到秒表这个功能，比如视频录制，游戏（1）

今天和大家讲的是Chronometer这个控件实现秒表功能 ，当然也可以用Handler实现。handler实现这里暂时不说 。接下来的一篇就是用handler实现。
用Chronometer很简单 直接上代码



main.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2007 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
 http://www.apache.org/licenses/LICENSE-2.0 
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:padding="4dip"
android:gravity="center_horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">

<Chronometer android:id="@+id/chronometer"
android:format="@string/chronometer_initial_format"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0"
android:paddingBottom="30dip"
android:paddingTop="30dip"
/>

<Button android:id="@+id/start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/chronometer_start">
<requestFocus />
</Button>

<Button android:id="@+id/stop"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/chronometer_stop">
</Button>

<Button android:id="@+id/reset"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/chronometer_reset">
</Button>

<Button android:id="@+id/set_format"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/chronometer_set_format">
</Button>

<Button android:id="@+id/clear_format"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/chronometer_clear_format">
</Button>

</LinearLayout>

mainactivity.java

package com.test.activity;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.app.WallpaperManager;
import android.content.Context;
import android.content.Intent;

import android.os.Bundle;
import android.os.SystemClock;

import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.Chronometer;
import android.widget.PopupWindow;
import android.widget.ViewFlipper;

public class MainActivity extends Activity {
Chronometer mChronometer;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Button button;

mChronometer = (Chronometer) findViewById(R.id.chronometer);

// Watch for button clicks.
button = (Button) findViewById(R.id.start);
button.setOnClickListener(mStartListener);

button = (Button) findViewById(R.id.stop);
button.setOnClickListener(mStopListener);

button = (Button) findViewById(R.id.reset);
button.setOnClickListener(mResetListener);

}

View.OnClickListener mStartListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.start();
}
};

View.OnClickListener mStopListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.stop();
//            mChronometer.setBase(SystemClock.elapsedRealtime());
//            System.out.println(SystemClock.elapsedRealtime());
}
};

View.OnClickListener mResetListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.setBase(SystemClock.elapsedRealtime());
System.out.println(SystemClock.elapsedRealtime());
}
};

View.OnClickListener mSetFormatListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.setFormat("Formatted time (%s)");
}
};

View.OnClickListener mClearFormatListener = new OnClickListener() {
public void onClick(View v) {
mChronometer.setFormat(null);
}
};
}

就这样Over了 简单吧。