使用Messenger类绑定服务显示时间

1、布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<Button
android:id="@+id/current_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="当前时间"
android:textColor="@android:color/black"
android:textSize="25dp" />

</LinearLayout>

2、创建CurrentTimeService类，继承Service类，内部类IncomingHandler类继承Handler类

public class CurrentTimeService extends Service {

public static final int CURRENT_TIME = 0;
private class IncomingHandler extends Handler{
@Override
public void handleMessage(Message msg) {
if(msg.what==CURRENT_TIME){
Time time = new Time();//创建Time对象
time.setToNow();//设置时间为当前时间
String currentTime = time.format("%Y-%m-%d %H:%M:%S");//设置时间格式
Toast.makeText(CurrentTimeService.this, currentTime, Toast.LENGTH_SHORT).show();
}else{
super.handleMessage(msg);
}
}
}
@Override
public IBinder onBind(Intent intent) {
Messenger messenger = new Messenger(new IncomingHandler());
return messenger.getBinder();
}
}

3、MainActivity

public class MainActivity extends Activity {

Messenger messenger;
boolean bound;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
protected void onStart() {
super.onStart();
Button button = (Button)findViewById(R.id.current_time);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this,CurrentTimeService.class);
bindService(intent,connection,BIND_AUTO_CREATE);//绑定服务
if(bound){
Message message = Message.obtain(null, CurrentTimeService.CURRENT_TIME, 0, 0);
try {
messenger.send(message);
} catch (RemoteException e) {
e.printStackTrace();
}
}
}
});
}
@Override
protected void onStop() {
super.onStop();
if(bound){
bound = false;
unbindService(connection);//解绑定
}
}
private ServiceConnection connection = new ServiceConnection(){
public void onServiceConnected(android.content.ComponentName name, android.os.IBinder service) {
messenger = new Messenger(service);

<span style="white-space:pre">		</span>bound = true;
};
public void onServiceDisconnected(android.content.ComponentName name) {
messenger = null;
bound = false;
}
};
}

4AndroidManifest.xml
<service android:name=".CurrentTimeService"/>