Question

我正在尝试使用YouTubePlayerSupportFragment将youtube视频整合到Fragment中。我使用了youtubeandroidplayerapi。我在logcat中遇到以下错误 -

FATAL EXCEPTION: main
    java.lang.NullPointerException
            at com.pepup.league.ui.fragments.VideosFragment.onCreateView(VideosFragment.java:109)
            at android.support.v4.app.Fragment.performCreateView(Fragment.java:1500)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:938)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1115)
            at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
            at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1478)
            at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:478)
            at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:1068)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:914)
            at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1436)
            at android.view.View.measure(View.java:15264)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:833)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:574)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4916)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4916)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4916)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:15264)
            at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:704)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4916)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at android.view.View.measure(View.java:15264)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:833)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:574)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4916)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
            at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2161)
            at android.view.View.measure(View.java:15264)
            at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2129)
            at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1240)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1433)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1125)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4607)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:747)
            at android.view.Choreographer.doCallbacks(Choreographer.java:567)
            at android.view.Choreographer.doFrame(Choreographer.java:536)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:733)
            at android.os.Handler.handleCallback(Handler.java:615)
            at android.os.Handler.dispatchMessage(Handler.java:92)
            at android.os.Looper.loop(Looper.java:153)
            at android.app.ActivityThread.main(ActivityThread.java:5086)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
            at dalvik.system.NativeStart.main(Native Method)

错误显示在行 -

 youTubePlayerSupportFragment.initialize(YoutubeDeveloperKey,new OnInitializedListener()

这是我的代码 -

VideosFragment.java

public class VideosFragment extends YouTubePlayerSupportFragment{
    private FragmentActivity myContext;
    private YouTubePlayer YPlayer;
    private static final String YoutubeDeveloperKey = "xyz";
    private static final int RECOVERY_DIALOG_REQUEST = 1;
    @Override
    public void onAttach(Activity activity) {
        if (activity instanceof FragmentActivity) {
            myContext = (FragmentActivity) activity;
        }
        super.onAttach(activity);
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.videos, container, false);


        rootView.setVerticalScrollBarEnabled(false);

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

        youTubePlayerSupportFragment.initialize(YoutubeDeveloperKey,new OnInitializedListener() {

            @Override
            public void onInitializationSuccess(Provider provider,
                                                YouTubePlayer player, boolean wasRestored) {
                // TODO Auto-generated method stub
                if (!wasRestored) {
                    YPlayer = player;
                    YPlayer.cueVideo("2zNSgSzhBfM");
                }
            }

            @Override
            public void onInitializationFailure(Provider provider,
                                                YouTubeInitializationResult errorReason) {
                // TODO Auto-generated method stub
                if (errorReason.isUserRecoverableError()) {
                    errorReason.getErrorDialog(myContext, RECOVERY_DIALOG_REQUEST).show();
                } else {
                    String errorMessage = String.format(
                            "There was an error initializing the YouTubePlayer",
                            errorReason.toString());
                    Toast.makeText(myContext, errorMessage, Toast.LENGTH_LONG).show();
                }
            }
        });
        return rootView;
    }


    @Override
    public void initialize(String s, OnInitializedListener onInitializedListener) {

    }
}

videos.xml

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="fill_parent"
    android:background="#FFFFFF">

    <RelativeLayout
        android:id="@+id/layout4"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"

        >

        <RelativeLayout
            android:id="@+id/layout1"
            android:layout_width="match_parent"
            android:layout_height="fill_parent"

            >

            <fragment
                android:name="com.google.android.youtube.player.YouTubePlayerSupportFragment"
                android:id="@+id/youtube_view"
                android:layout_width="match_parent"
                android:layout_height="240dp"
                android:layout_marginLeft="62dp"
                android:layout_marginRight="32dp"

                android:cropToPadding="true"
                android:padding="1dp"
                android:scaleType="centerCrop" />

        </RelativeLayout>

    </RelativeLayout>
</ScrollView>

Answer 1

想出了这个问题。如果我使用getChildFragmentManager()方法，那么它可以工作。

YouTubePlayerSupportFragment youTubePlayerFragment = (YouTubePlayerSupportFragment)getChildFragmentManager().
    findFragmentById(R.id.add_edit_youtube_youtube_fragment);

Answer 2

我也有这个问题。在 Vikas Gupta 的提示旁边，使用getChildFragmentManager()，我还必须将与该片段相关的代码移到onViewCreated()：

@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);

youTubePlayerFragment = (YouTubePlayerSupportFragment) getChildFragmentManager()
            .findFragmentById(R.id.youtube_player_fragment);

youTubePlayerFragment.initialize(BuildConfig.API_KEY,
            new YouTubePlayer.OnInitializedListener() {
                @Override
                public void onInitializationSuccess(YouTubePlayer.Provider provider,
                                                    YouTubePlayer player, boolean b) {
                    // code when initialization is successful
                    }

                @Override
                public void onInitializationFailure(YouTubePlayer.Provider provider,
                                 YouTubeInitializationResult youTubeInitializationResult) {
                        Timber.e("Youtube Player could not be initialized.");
                    //handle error
                }
           });
}

看起来片段在视图仍在创建时返回null。因此，在调用和处理youtube片段之前，我必须等待完成。

initialize（）方法中的YouTubePlayerSupportFragment-null指针异常

2 个答案: