YouTubePlayerSupportFragment Null Pointer Exception

Question

Раньше мой код работал нормально, я использовал YoutubeBaseActivity, чтобы расширить свой класс java, теперь я использую AppCompatActivity по некоторым причинам и получаю NPE.

Это линия, где я получаю NPE:

youTubePlayerSupportFragment.initialize(ApiKey.YOUTUBE_API_KEY, this); 

YouTubeViewActivity.java здесь полный код

public class YouTubeViewActivity extends AppCompatActivity implements 
     YouTubePlayer.OnInitializedListener { 

    private static final int RECOVERY_DIALOG_REQUEST = 1; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     setContentView(R.layout.youtube_view_activity); 

     YouTubePlayerSupportFragment youTubePlayerSupportFragment = 
       (YouTubePlayerSupportFragment) getSupportFragmentManager().findFragmentById(R.id.youtube_view); 

     // at below line I am getting NPE 
     youTubePlayerSupportFragment.initialize(ApiKey.YOUTUBE_API_KEY, this); 

    } 

    @Override 
    public void onInitializationFailure(YouTubePlayer.Provider provider, 
      YouTubeInitializationResult errorReason) { 
     if (errorReason.isUserRecoverableError()) { 
      errorReason.getErrorDialog(this, RECOVERY_DIALOG_REQUEST).show(); 
     } else { 
      String errorMessage = String.format(
        getString(R.string.error_player), errorReason.toString()); 
      Toast.makeText(this, errorMessage, Toast.LENGTH_LONG).show(); 
     } 
    } 

    @Override 
    public void onInitializationSuccess(YouTubePlayer.Provider provider, 
      YouTubePlayer player, boolean wasRestored) { 
     if (!wasRestored) { 

      player.loadVideo("pRpeEdMmmQ0"); // cue, load 

     } 
    } 

    @Override 
    protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
     if (requestCode == RECOVERY_DIALOG_REQUEST) { 
      // Retry initialization if user performed a recovery action 
      getYouTubePlayerProvider().initialize(ApiKey.YOUTUBE_API_KEY, this); 
     } 
    } 

    private YouTubePlayer.Provider getYouTubePlayerProvider() { 
     return (YouTubePlayerView) findViewById(R.id.youtube_view); 
    } 

} 

youtube_view_activity.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:orientation="vertical"> 

    <fragment 
     android:name="com.google.android.youtube.player.YouTubePlayerFragment" 
     android:id="@+id/youtube_view" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent"/> 

</LinearLayout> 

См Log:

FATAL EXCEPTION: main 
                    Process: com.akoscz.youtube, PID: 13033 
                    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.akoscz.youtube/com.akoscz.youtube.YouTubeViewActivity}: java.lang.NullPointerException 
                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2338) 
                     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390) 
                     at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321) 
                     at android.os.Handler.dispatchMessage(Handler.java:110) 
                     at android.os.Looper.loop(Looper.java:193) 
                     at android.app.ActivityThread.main(ActivityThread.java:5299) 
                     at java.lang.reflect.Method.invokeNative(Native Method) 
                     at java.lang.reflect.Method.invoke(Method.java:515) 
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829) 
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645) 
                     at dalvik.system.NativeStart.main(Native Method) 
                    Caused by: java.lang.NullPointerException 
                     at com.akoscz.youtube.YouTubeViewActivity.onCreate(YouTubeViewActivity.java:28) 
                     at android.app.Activity.performCreate(Activity.java:5264) 
                     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1088) 
                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2302) 
                     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)  
                     at android.app.ActivityThread.access$800(ActivityThread.java:151)  
                     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)  
                     at android.os.Handler.dispatchMessage(Handler.java:110)  
                     at android.os.Looper.loop(Looper.java:193)  
                     at android.app.ActivityThread.main(ActivityThread.java:5299)  
                     at java.lang.reflect.Method.invokeNative(Native Method)  
                     at java.lang.reflect.Method.invoke(Method.java:515)  
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:829)  
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:645)  
                     at dalvik.system.NativeStart.main(Native Method)  

Answer 1

Вы получили неправильный Fragment класс в макете. Он должен быть com.google.android.youtube.player.YouTubePlayerSupportFragment.

Поддержка FragmentManager только опорные ручки Fragment с, поэтому getSupportFragmentManager().findFragmentById() вызова не найти YouTubePlayerFragment в макете, и просто возвращает нуль.