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android bindService() NullPointerException

2024-08-09 02:34:41   218人阅读

android app开发中 下面的代码报错误 ,bindService() NullPointerException


 

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publicclass MainActivity extendsActivity implementsOnClickListener{
 
Button but;
 
Button but2;
 
LocalBinder binder;
 
@Override
 
protectedvoid onCreate(Bundle savedInstanceState) {
 
super.onCreate(savedInstanceState);
 
setContentView(R.layout.activity_main);
 
but = (Button) findViewById(R.id.button1);
 
but.setOnClickListener(this);
 
but = (Button) findViewById(R.id.button2);
 
}
 
 
ServiceConnection connection = newServiceConnection(){
 
 
 
@Override
 
publicvoid onServiceConnected(ComponentName arg0, IBinder arg1) {
 
Log.d("D1","connecting");
 
binder = (LocalBinder) arg1;
 
 
}
 
 
 
@Override
 
publicvoid onServiceDisconnected(ComponentName arg0) {
 
Log.d("D1","disconnecting");
 
 
}
 
 
};
 
 
publicstatic class ServiceTest extendsService{
 
 
 
@Override
 
publicIBinder onBind(Intent arg0) {
 
// TODO Auto-generated method stub
 
returnnew LocalBinder();
 
}
 
 
publicclass LocalBinder extendsBinder{
 
publicvoid toast(){
 
Toast.makeText(getApplicationContext(),"hope this works", Toast.LENGTH_LONG).show();
 
}
 
}
 
}
 
 
 
@Override
 
publicvoid onClick(View arg0) {
 
Intent i = newIntent(getApplicationContext(), ServiceTest.LocalBinder.class);
 
bindService(i, connection, Context.BIND_AUTO_CREATE);
 
Toast.makeText(getApplicationContext(),"bind completed", Toast.LENGTH_LONG).show();
 
}
 
 
publicvoid binderMethod(View v){
 
binder.toast();
 
}
}
}


我自己分析了下感觉是 onServiceConnected 没有执行，所以才会引起空指针

在but2执行调用 binder.toast() 的时候 会绑定 service 和 activity
当我点击btn2的时候才抛出这个异常.

为什么 onServiceConnected 没有执行？

处理方法

 intent 在调用service的时候并没有绑定service

1
Intent i = newIntent(getApplicationContext(), ServiceTest.class);

 


原文地址：http://www.itmmd.com/201411/95.html 
该文章由 萌萌的IT人 整理发布,转载须标明出处。

android bindService() NullPointerException


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