Android Service控件用法实例分析

<service android:name="MyService">
  <intent-filter>
    <action android:name="hb.com.MYSERVICE"/>
  </intent-filter>
</service>

public class MyService extends Service {
  public class MyBinder extends Binder{
    public MyService getMyService(){
      return MyService.this;
    }
  }
  public void test(){
    System.out.println("test");
  }
  @Override
  public IBinder onBind(Intent intent) {
    // TODO Auto-generated method stub
    System.out.println("onBind");
    return new MyBinder();
  }
  @Override
  public void onCreate() {
    // TODO Auto-generated method stub
    System.out.println("onCreate");
    super.onCreate();
  }
  @Override
  public boolean onUnbind(Intent intent) {
    System.out.println("I am unbind");
    return super.onUnbind(intent);
  }
}

public class MainActivity extends Activity {
  private static final String MYSERVICE = "hb.com.MYSERVICE";
  private boolean flag = false;
  //bindService()方法需要ServiceConnection接口作为参数，所以定义了这个变量，目的是为了实现里面的两个方法
  ServiceConnection conn = new ServiceConnection() {
    @Override
    public void onServiceDisconnected(ComponentName name) {
      System.out.println("onServiceDisconnected");
    }
    @Override
    public void onServiceConnected(ComponentName name, IBinder service) {
      System.out.println("onServiceConnected");
      MyBinder myBinder = (MyBinder)service;
      MyService myService = myBinder.getMyService();
      myService.test();
    }
  };
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    findViewById(R.id.start).setOnClickListener(new Button.OnClickListener(){
      @Override
      public void onClick(View v) {
        Intent intent = new Intent();
        intent.setAction(MYSERVICE);
        //先调用MyService的onCreate()方法，然后调用onBind()方法，最后调用onServiceConnected()方法
        //因此IBinder返回的值就是通过onBind()方法返回的对象，定义getMyService()方法是为了得到MyService对象，用户在这个类中添加自己需要的一些方法，这样可以做一些逻辑处理
        bindService(intent, conn, Service.BIND_AUTO_CREATE);
        flag = true;
      }
    });
    findViewById(R.id.stop).setOnClickListener(new Button.OnClickListener(){
      @Override
      public void onClick(View v) {
        if(flag){
          //取消绑定事件，会调用MyService的onUnbind()方法，但是不会调用onServiceDisconnected()这个方法，原因不明
          unbindService(conn);
          flag = false;
        }
      }
    });
  }
}