фатальное исключение в приемнике

Question

это код для приемника, расширяющего BroadcastReceiver. каждый раз, когда я устанавливаю его, и телефон звонит, он внезапно останавливается и дает эту ошибку. Я нахожу этот код здесь How to detect incoming calls, in an Android device?

public abstract class PhonecallReceiver extends BroadcastReceiver { 

//The receiver will be recreated whenever android feels like it. We need a static variable to remember data between instantiations 
static PhonecallStartEndDetector listener; 
String outgoingSavedNumber; 
protected Context savedContext; 


@Override 
public void onReceive(Context context, Intent intent) { 
    savedContext = context; 
    if(listener == null){ 
     listener = new PhonecallStartEndDetector(); 
    } 

    //We listen to two intents. The new outgoing call only tells us of an outgoing call. We use it to get the number. 
    if (intent.getAction().equals("android.intent.action.NEW_OUTGOING_CALL")) { 
     listener.setOutgoingNumber(intent.getExtras().getString("android.intent.extra.PHONE_NUMBER")); 
     return; 
    } 

    //The other intent tells us the phone state changed. Here we set a listener to deal with it 
    TelephonyManager telephony = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE); 
    telephony.listen(listener, PhoneStateListener.LISTEN_CALL_STATE); 
} 

//Derived classes should override these to respond to specific events of interest 
protected abstract void onIncomingCallStarted(String number, Date start); 
protected abstract void onOutgoingCallStarted(String number, Date start); 
protected abstract void onIncomingCallEnded(String number, Date start, Date end); 
protected abstract void onOutgoingCallEnded(String number, Date start, Date end); 
protected abstract void onMissedCall(String number, Date start); 

    //Deals with actual events 
    public class PhonecallStartEndDetector extends PhoneStateListener { 
    int lastState = TelephonyManager.CALL_STATE_IDLE; 
    Date callStartTime; 
    boolean isIncoming; 
    String savedNumber; //because the passed incoming is only valid in ringing 

    public PhonecallStartEndDetector() {} 

    //The outgoing number is only sent via a separate intent, so we need to store it out of band 
    public void setOutgoingNumber(String number){ 
     savedNumber = number; 
    } 

    //Incoming call- goes from IDLE to RINGING when it rings, to OFFHOOK when it's answered, to IDLE when its hung up 
    //Outgoing call- goes from IDLE to OFFHOOK when it dials out, to IDLE when hung up 
    @Override 
    public void onCallStateChanged(int state, String incomingNumber) { 
     super.onCallStateChanged(state, incomingNumber); 
     if(lastState == state){ 

      return; 
     } 
     switch (state) { 
      case TelephonyManager.CALL_STATE_RINGING: 
       isIncoming = true; 
       callStartTime = new Date(); 
       savedNumber = incomingNumber; 
       onIncomingCallStarted(incomingNumber, callStartTime); 
       Log.i("", "2"); 

       break; 
      case TelephonyManager.CALL_STATE_OFFHOOK: 
       //Transition of ringing->offhook are pickups of incoming calls. Nothing donw on them 
       if(lastState != TelephonyManager.CALL_STATE_RINGING){ 
        isIncoming = false; 
        callStartTime = new Date(); 
        onOutgoingCallStarted(savedNumber, callStartTime); 
        Log.i("", "3"); 

       } 
       break; 
      case TelephonyManager.CALL_STATE_IDLE: 
       //Went to idle- this is the end of a call. What type depends on previous state(s) 
       if(lastState == TelephonyManager.CALL_STATE_RINGING){ 
        //Ring but no pickup- a miss 
        onMissedCall(savedNumber, callStartTime); 
        Log.i("", "4"); 

       } 
       else if(isIncoming){ 
        onIncomingCallEnded(savedNumber, callStartTime, new Date()); 
        Log.i("", "5"); 

       } 
       else{ 
        onOutgoingCallEnded(savedNumber, callStartTime, new Date());  
        Log.i("", "6"); 

       } 
       break; 
     } 
     lastState = state; 
    } 

} 



} 

ошибку здесь:

10-09 09:51:08.656: E/AndroidRuntime(4249): FATAL EXCEPTION: main 
10-09 09:51:08.656: E/AndroidRuntime(4249): java.lang.RuntimeException:  Unable to instantiate receiver android.call.PhonecallReceiver:  java.lang.InstantiationException: can't instantiate class android.call.PhonecallReceiver 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at  android.app.ActivityThread.handleReceiver(ActivityThread.java:2460) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at  android.app.ActivityThread.access$1500(ActivityThread.java:150) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1374) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at android.os.Handler.dispatchMessage(Handler.java:99) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at android.os.Looper.loop(Looper.java:213) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at android.app.ActivityThread.main(ActivityThread.java:5225) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at java.lang.reflect.Method.invokeNative(Native Method) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at java.lang.reflect.Method.invoke(Method.java:525) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:741) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at  dalvik.system.NativeStart.main(Native Method) 
10-09 09:51:08.656: E/AndroidRuntime(4249): Caused by: java.lang.InstantiationException: can't instantiate class android.call.PhonecallReceiver 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at  java.lang.Class.newInstanceImpl(Native Method) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at java.lang.Class.newInstance(Class.java:1130) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  at android.app.ActivityThread.handleReceiver(ActivityThread.java:2455) 
10-09 09:51:08.656: E/AndroidRuntime(4249):  ... 10 more 

Answer 1

Вы не можете создать экземпляр абстрактного класса. Вы должны сделать его обычным публичным классом, а также определить его в файле манифеста. Надеюсь, что сработает