对不起我的英语不好
我有一个通过 Messenger 与服务通信的活动。当我启动 Activity 并按下使 unbindservice 没有首先进行 bindservice 的按钮时，我的应用程序向我发送 NullPointerException 并且我的 Activity 崩溃。
日志猫。
6-30 20:38:26.802: E/AndroidRuntime(29453): FATAL EXCEPTION: main
06-30 20:38:26.802: E/AndroidRuntime(29453): java.lang.NullPointerException
06-30 20:38:26.802: E/AndroidRuntime(29453): at com.example.servicetest.MainActivity.doUnbindService(MainActivity.java:180)
06-30 20:38:26.802: E/AndroidRuntime(29453): at com.example.servicetest.MainActivity$3.onClick(MainActivity.java:109)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.view.View.performClick(View.java:4261)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.view.View$PerformClick.run(View.java:17356)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.os.Handler.handleCallback(Handler.java:615)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.os.Handler.dispatchMessage(Handler.java:92)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.os.Looper.loop(Looper.java:137)
06-30 20:38:26.802: E/AndroidRuntime(29453): at android.app.ActivityThread.main(ActivityThread.java:4921)
06-30 20:38:26.802: E/AndroidRuntime(29453): at java.lang.reflect.Method.invokeNative(Native Method)
06-30 20:38:26.802: E/AndroidRuntime(29453): at java.lang.reflect.Method.invoke(Method.java:511)
06-30 20:38:26.802: E/AndroidRuntime(29453): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
06-30 20:38:26.802: E/AndroidRuntime(29453): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
06-30 20:38:26.802: E/AndroidRuntime(29453): at dalvik.system.NativeStart.main(Native Method)
06-30 20:38:26.852: E/android.os.Debug(2019): !@Dumpstate > dumpstate -k -t -z -d -o /data/log/dumpstate_app_error
我的活动代码。
public class MainActivity extends Activity {
/** Messenger for communicating with the service. */
Messenger mService = null;
Boolean mBound;
Button button1,button2,button3,button4,button5,button6;
Intent intent_serv;
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
mService = new Messenger(service);
mBound=true;
Toast.makeText(getBaseContext(), "Conectado-Binding",Toast.LENGTH_SHORT).show();
}
public void onServiceDisconnected(ComponentName className) {
// This is called when the connection with the service has been unexpectedly disconnected - process crashed.
mService = null;
mBound=false;
Toast.makeText(getBaseContext(), "Desconectado-Unbinding",Toast.LENGTH_SHORT).show();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1=(Button)findViewById(R.id.button1);
button2=(Button)findViewById(R.id.button2);
button3=(Button)findViewById(R.id.button3);
button4=(Button)findViewById(R.id.button4);
button5=(Button)findViewById(R.id.button5);
button6=(Button)findViewById(R.id.button6);
button1.setOnClickListener(new OnClickListener() {
//start Service
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Log.i("PruebaService", "Boton Start Service");
// Bind to the service
intent_serv=new Intent(MainActivity.this, PruebaService.class);
startService(intent_serv);
}
});
button2.setOnClickListener(new OnClickListener() {
//Stop Service
@Override
public void onClick(View v) {
Log.i("PruebaService", "Boton Parar Service");
// TODO Auto-generated method stub
intent_serv=new Intent(MainActivity.this,PruebaService.class);
stopService(intent_serv);
}
});
button3.setOnClickListener(new OnClickListener() {
// Bind service.
@Override
public void onClick(View v) {
Log.i("PruebaService", "Boton Bind Service");
// TODO Auto-generated method stub
MainActivity.this.bindService(intent_serv, mConnection,Context.BIND_AUTO_CREATE);
}
});
button4.setOnClickListener(new OnClickListener() {
// Unbind service.
@Override
public void onClick(View v) {
Log.i("PruebaService", "Boton Unbound-Status mBound:"+mBound);
// TODO Auto-generated method stub
if (mBound) {
MainActivity.this.unbindService(mConnection);
mBound = false;
}else{
Log.i("PruebaService", "PAso al Else.");
}
}
});
button5.setOnClickListener(new OnClickListener() {
// Bind service.
@Override
public void onClick(View v) {
Log.i("PruebaService", "Boton message to service 1");
// TODO Auto-generated method stub
}
});
button6.setOnClickListener(new OnClickListener() {
// Bind service.
@Override
public void onClick(View v) {
Log.i("PruebaService", "Boton message to service 10");
}
});
}
@Override
protected void onDestroy() {
super.onStop();
Log.i("PruebaService", "Estado mBound :"+mBound+"Estado mConnection :"+mConnection);
// Unbind from the service
if (mBound && mConnection!=null) {
MainActivity.this.unbindService(mConnection);
mBound = false;
}
}
我的服务代码。
public class PruebaService extends Service{
private NotificationManager nm;
static final int MSG_REGISTER_CLIENT = 1;
static final int MSG_UNREGISTER_CLIENT = 2;
static final int MSG_SET_INT_VALUE = 3;
static final int MSG_SET_STRING_VALUE = 4;
static final int MSG_SET_RESP_A = 5;
static final int MSG_SET_RESP_B = 6;
final Messenger mMessenger = new Messenger(new IncomingHandler()); // Target we publish for clients to send messages to IncomingHandler.
@Override
public IBinder onBind(Intent intent) {
return mMessenger.getBinder();
}
class IncomingHandler extends Handler { // Handler of incoming messages from clients.
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_SET_RESP_A:
//incrementby = msg.arg1;
break;
case MSG_SET_RESP_B:
// incrementby = msg.arg1;
break;
default:
super.handleMessage(msg);
}
}
}
@Override
public void onCreate() {
super.onCreate();
Log.i("PruebaService", "Service Started.");
showNotification();
//timer.scheduleAtFixedRate(new TimerTask(){ public void run() {onTimerTick();}}, 0, 100L);
}
private void showNotification() {
nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
// In this sample, we'll use the same text for the ticker and the expanded notification
CharSequence text = getText(R.string.service_started);
// Set the icon, scrolling text and timestamp
Notification notification = new Notification(R.drawable.advertencia, text, System.currentTimeMillis());
// The PendingIntent to launch our activity if the user selects this notification
PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, MainActivity.class), 0);
// Set the info for the views that show in the notification panel.
notification.setLatestEventInfo(this, getText(R.string.service_label), text, contentIntent);
// Send the notification.
// We use a layout id because it is a unique number. We use it later to cancel.
nm.notify(R.string.service_started, notification);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.i("PruebaService", "Received start id " + startId + ": " + intent);
return START_STICKY; // run until explicitly stopped.
}
@Override
public void onDestroy() {
super.onDestroy();
//if (timer != null) {timer.cancel();}
nm.cancel(R.string.service_started); // Cancel the persistent notification.
Log.i("PruebaService", "Service Stopped.");
}
我希望你能帮助我解决我的问题。