Service的onServiceConnected没有被调用

Service的onServiceConnected没有被调用

分类： android学习2011-07-28
15:07 2886人阅读 评论(0) 收藏 举报

servicebuttonclassimportandroidnull

Service是一种运行在后台的服务，一般很少与用户交互，所以没有可视化界面。

我们可以通过startService() 或者使用bindService()方法来绑定一个存在的service。

bindService是异步调用和Service进行绑定, 如果绑定成功, 则会调用ServiceConnection的onServiceConnected

当调用bindService方法后就会回调Activity的onServiceConnected，在这个方法中会向Activity中传递一个IBinder的实例，Acitity需要保存这个实例

在Service中需要创建一个实现IBinder的内部类(这个内部类不一定在Service中实现，但必须在Service中创建它)。

在OnBind（）方法中需返回一个IBinder实例，不然onServiceConnected方法不会调用。

[java] view
plaincopy



[java] view
plaincopy

import android.app.Activity;

import android.content.ComponentName;

import android.content.Intent;

import android.content.ServiceConnection;

import android.os.Bundle;

import android.os.IBinder;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.Toast;



public class ServiceActivity extends Activity {

/** Called when the activity is first created. */

private Button start;

private Button stop;

private Button bind;

private Button unbind;



@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

start =(Button) findViewById(R.id.start);

stop = (Button) findViewById(R.id.stop);

bind = (Button) findViewById(R.id.bind);

unbind = (Button) findViewById(R.id.unbind);

//启动一个service

start.setOnClickListener(new OnClickListener() {



@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

Intent intent = new Intent();

System.out.println("start....");

intent.setAction("com.shao.service.action.MyService");

startService(intent);

}

});

//结束一个service

stop.setOnClickListener(new OnClickListener() {



@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

Intent intent = new Intent();

System.out.println("stop....");

intent.setAction("com.shao.service.action.MyService");

stopService(intent);

}

});



//绑定一个service

bind.setOnClickListener(new OnClickListener() {



@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

Intent intent = new Intent();

System.out.println("bind..");

intent.setAction("com.shao.service.action.MyService");

bindService(intent, conn, BIND_AUTO_CREATE);

}

});

//解除绑定的service

unbind.setOnClickListener(new OnClickListener() {



@Override

public void onClick(View arg0) {

// TODO Auto-generated method stub

Intent intent = new Intent();

System.out.println("unbind..");

intent.setAction("com.shao.service.action.MyService");

unbindService(conn);

}

});

}



private ServiceConnection conn = new ServiceConnection() {



@Override

public void onServiceDisconnected(ComponentName arg0) {

// TODO Auto-generated method stub

Toast.makeText(ServiceActivity.this,"disconn successful" ,Toast.LENGTH_LONG);

}



@Override

public void onServiceConnected(ComponentName name, IBinder service) {

// TODO Auto-generated method stub

Toast.makeText(ServiceActivity.this,"conn successful" ,Toast.LENGTH_LONG);

}

};

}

[java] view
plaincopy



MyService文件：

[java] view
plaincopy



[java] view
plaincopy

import android.app.Service;

import android.content.Intent;

import android.os.Binder;

import android.os.IBinder;

import android.os.Parcel;

import android.widget.Toast;



public class MyService extends Service {

@Override

public IBinder onBind(Intent intent) {

// TODO Auto-generated method stub

System.out.println("onBind.....");

IBinder result = null;

if ( null == result ) result = new MyBinder() ;

Toast.makeText(this, "onBind",Toast.LENGTH_LONG);

return result;

}



@Override

public void onCreate() {

// TODO Auto-generated method stub

super.onCreate();

System.out.println("onCreate.....");

Toast.makeText(this, "onCreate",Toast.LENGTH_LONG);

}



@Override

public void onDestroy() {

// TODO Auto-generated method stub

super.onDestroy();

System.out.println("onDestory.....");

Toast.makeText(this, "onDestroy",Toast.LENGTH_LONG);

}



@Override

public void onStart(Intent intent, int startId) {

// TODO Auto-generated method stub

super.onStart(intent, startId);

System.out.println("onStart...");

Toast.makeText(this, "onStart",Toast.LENGTH_LONG);

}

public class MyBinder extends Binder {

//此方法是为了可以在Acitity中获得服务的实例

public MyService getService() {

return MyService.this;

}



}

}

Service需在mainifest文件中声明:

<service android:name="MyService">

<intent-filter>

<action android:name="com.shao.service.action.MyService"/>

</intent-filter>

</service>

分享到：

上一篇：可拖拽的ImageButton
下一篇：PopupWindow泡泡效果