碼表Chronometer

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="${relativePackage}.${activityClass}" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

    <Chronometer
        android:id="@+id/chronometer1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Chronometer"
        android:textSize="50sp" />

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

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="doStop"
        android:text="stop" />

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="doPause"
        android:text="pause" />

</LinearLayout>

package com.example.app23;

import android.app.Activity;
import android.os.Bundle;
import android.os.SystemClock;
import android.view.View;
import android.widget.Chronometer;

public class MainActivity extends Activity {

    Chronometer chronometer1;
    long pauseTime;// 暫停的時間

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        chronometer1 = (Chronometer) this.findViewById(R.id.chronometer1);

    }

    public void doStart(View view) {

        if (pauseTime == 0) {
            chronometer1.setBase(SystemClock.elapsedRealtime());//設定開始碼表的基準點(時間)
            chronometer1.start();
        } else {
            long offset = SystemClock.elapsedRealtime() - pauseTime;
            chronometer1.setBase(chronometer1.getBase() + offset);
            chronometer1.start();
        }
    }

    public void doStop(View view) {
        chronometer1.stop();
        pauseTime=0;
    }

    public void doPause(View view) {
        chronometer1.stop();
        pauseTime= SystemClock.elapsedRealtime();
    }
}