MainActivity
package com.example.clock;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.Date;
public class MainActivityextends AppCompatActivityimplements Button.OnClickListener{
Buttonstart, stop, clear;
TextViewshow;
Datebgtime;
long bg =0;
boolean isFirst=true, isStop=false;
Handlerhandler =new Handler();
private Runnablerunnable =new Runnable() {
@Override
public void run() {
if(!isStop){
show.setText(timeFormat(bg + (new Date().getTime()) -bgtime.getTime()));
handler.post(this);
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
start = (Button) findViewById(R.id.start);
clear = (Button) findViewById(R.id.clear);
stop = (Button) findViewById(R.id.stop);
start.setOnClickListener(this);
stop.setOnClickListener(this);
clear.setOnClickListener(this);
show = (TextView) findViewById(R.id.show);
}
@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.start:
if(isFirst){
isFirst =false;
isStop =false;
bgtime =new Date();
new Thread(runnable).run();
}
break;
case R.id.stop:
bg += (new Date().getTime()) -bgtime.getTime();
isStop =true;
isFirst =true;
break;
case R.id.clear:
show.setText("00:00:00.00");
bg =0;
isStop =true;
isFirst =true;
break;
}
}
public StringtimeFormat(long ms)
{
int sm = (int) (ms%1000)/10;
ms = (int) ms/1000;
int sec = (int) ms%60;
int min = (int) ms/60;
int h = (int) ms/3600;
return String.format("%02d:%02d:%02d.%02d",h, min, sec, sm);
}
}
layout.xml
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:rowCount="4"
android:columnCount="3"
tools:context="com.example.clock.MainActivity"
>
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1"
android:layout_gravity="center_horizontal"
android:layout_row="0"
android:text="计时器"
android:textSize="30dp"/>
android:id="@+id/show"
android:layout_columnSpan="3"
android:text="00:00:00.00"
android:textSize="40dp"
android:layout_gravity="center_horizontal"/>
android:id="@+id/clear"
android:text="清零"
android:layout_row="2"
android:layout_column="0"/>
android:id="@+id/start"
android:text="计时"
android:layout_row="2"
android:layout_column="1"
android:layout_gravity="center_horizontal"/>
android:id="@+id/stop"
android:text="停止"
android:layout_row="2"
android:layout_column="2"/>
