title: Android: BroadcastReceiver
body: <p>I am trying to listen to the phone state when contact is calling me but i am getting some error.</p>
  
  <p>ServiceReceiver.java</p>
  
  <pre><code>package org.example.servicereceiver;
  
  import android.content.BroadcastReceiver;
  import android.content.Context;
  import android.content.Intent;
  import android.telephony.PhoneStateListener;
  import android.telephony.TelephonyManager;
  import android.util.Log;
  
  
  public class ServiceReceiver extends BroadcastReceiver {
  
      private static final String TAG = "ServiceReceiver"; 
  
      @Override
      public void onReceive(Context context, Intent intent) {
          MyPhoneStateListener phoneListener=new MyPhoneStateListener();
          TelephonyManager telephony = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
          Log.d(TAG, "telephony: " + telephony);
  
          telephony.listen(phoneListener,PhoneStateListener.LISTEN_CALL_STATE);
      }
  }
  </code></pre>
  
  <p>MyPhoneStateListener.java</p>
  
  <pre><code>package org.example.servicereceiver;
  
  import android.telephony.PhoneStateListener;
  import android.telephony.TelephonyManager;
  import android.util.Log;
  
  public class MyPhoneStateListener extends PhoneStateListener {
      public void onCallStateChanged(int state,String incomingNumber){
          switch(state)
          {
             case TelephonyManager.CALL_STATE_IDLE:
                  Log.d("DEBUG", "IDLE");
                  break;
             case TelephonyManager.CALL_STATE_OFFHOOK:
                  Log.d("DEBUG", "OFFHOOK");
                  break;
             case TelephonyManager.CALL_STATE_RINGING:
                 Log.d("DEBUG", "RINGING");
                 break;
          }
      }   
  
  }
  </code></pre>
  
  <p>Errors:</p>
  
  <pre><code>04-13 18:25:21.845: ERROR/AndroidRuntime(14861): FATAL EXCEPTION: main
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{org.example.servicereceiver/org.example.servicereceiver.ServiceReceiver}: java.lang.ClassCastException: org.example.servicereceiver.ServiceReceiver
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2709)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2803)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread.access$2300(ActivityThread.java:135)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2136)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.os.Handler.dispatchMessage(Handler.java:99)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.os.Looper.loop(Looper.java:144)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread.main(ActivityThread.java:4937)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at java.lang.reflect.Method.invokeNative(Native Method)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at java.lang.reflect.Method.invoke(Method.java:521)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at dalvik.system.NativeStart.main(Native Method)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861): Caused by: java.lang.ClassCastException: org.example.servicereceiver.ServiceReceiver
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.Instrumentation.newActivity(Instrumentation.java:1036)
  04-13 18:25:21.845: ERROR/AndroidRuntime(14861):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2701)
  </code></pre>
  
  <p>XML:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="org.example.servicereceiver"
        android:versionCode="1"
        android:versionName="1.0"&gt;
      &lt;application android:icon="@drawable/icon" android:label="@string/app_name"&gt;
          &lt;activity android:name=".ServiceReceiver"
                    android:label="@string/app_name"&gt;
              &lt;intent-filter&gt;
                  &lt;action android:name="android.intent.action.MAIN" /&gt;
                  &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
              &lt;/intent-filter&gt;
          &lt;/activity&gt;
          &lt;receiver android:name=".ServiceReceiver"&gt;
          &lt;intent-filter&gt;
          &lt;action android:name="android.intent.action.PHONE_STATE"/&gt;
          &lt;/intent-filter&gt;
          &lt;/receiver&gt;
  
      &lt;/application&gt;
      &lt;uses-sdk android:minSdkVersion="8" /&gt;
      &lt;uses-permission android:name="android.permission.READ_PHONE_STATE"/&gt;
  
  &lt;/manifest&gt; 
  </code></pre>