Question

我正在使用Volley进行网络通话！此外，我使用LRU缓存来缓存图像并使用齐射自己的NetworkImageView进行填充。到目前为止一切正常！然而，当我在我的Application类中调用初始ACRA（Crash reporter）时，Volley正在创建NullPointerException。我绝对不知道在哪里寻找这个bug。这是我的Application类的代码。

AppController.class

    @ReportsCrashes()

public class AppController extends Application
{
    public static final String TAG = AppController.class.getSimpleName();

    private RequestQueue mRequestQueue;
    private ImageLoader mImageLoader;



    private static AppController mInstance;

    @Override
    public void onCreate() {
        super.onCreate();
        ACRA.init(this);

    }

    public static synchronized AppController getInstance() {
        return mInstance;
    }

    public RequestQueue getRequestQueue() {
        if (mRequestQueue == null) {
            mRequestQueue = Volley.newRequestQueue(getApplicationContext());
        }

        return mRequestQueue;
    }

    public ImageLoader getImageLoader() {
        getRequestQueue();
        if (mImageLoader == null) {
            mImageLoader = new ImageLoader(this.mRequestQueue,
                    new LruBitmapCache());
        }
        return this.mImageLoader;
    }

    public <T> void addToRequestQueue(Request<T> req, String tag) {
        // set the default tag if tag is empty
        req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
        getRequestQueue().add(req);
    }

    public <T> void addToRequestQueue(Request<T> req) {
        req.setTag(TAG);
        getRequestQueue().add(req);
    }

    public void cancelPendingRequests(Object tag) {
        if (mRequestQueue != null) {
            mRequestQueue.cancelAll(tag);
        }
    }
}

我的RecyclerView的适配器中抛出了异常，其中我填充了缓存的项目。

CustomAdapter.class

ImageLoader imageLoader = AppController.getInstance().getImageLoader();
ImageLoader imageLoader2 = AppController.getInstance().getImageLoader();

logcat输出为：

E / AndroidRuntime：致命异常：主要过程：com.mobloo.eduknow，PID：28295 java.lang.NullPointerException：尝试调用虚方法＆＃39; com.android.volley.toolbox.ImageLoader com.mobloo.eduknow.AppController.getImageLoader（）＆＃39;在null对象上参考在com.mobloo.eduknow.CustomAdapter。（CustomAdapter.java:33）在com.mobloo.eduknow.FeedsFragment.onCreateView（FeedsFragment.java:57）在android.support.v4.app.Fragment.performCreateView（Fragment.java:1962）在android.support.v4.app.FragmentManagerImpl.moveToState（FragmentManager.java:1067）在android.support.v4.app.FragmentManagerImpl.moveToState（FragmentManager.java:1248）在android.support.v4.app.BackStackRecord.run（BackStackRecord.java:738）在android.support.v4.app.FragmentManagerImpl.execPendingActions（FragmentManager.java:1613）在android.support.v4.app.FragmentManagerImpl.executePendingTransactions（FragmentManager.java:570）在android.support.v4.app.FragmentPagerAdapter.finishUpdate（FragmentPagerAdapter.java:141）在android.support.v4.view.ViewPager.populate（ViewPager.java:1106）在android.support.v4.view.ViewPager.populate（ViewPager.java:952）在android.support.v4.view.ViewPager.onMeasure（ViewPager.java:1474）在android.view.View.measure（View.java:18794）在android.widget.RelativeLayout.measureChildHorizontal（RelativeLayout.java:715）在android.widget.RelativeLayout.onMeasure（RelativeLayout.java:461）在android.view.View.measure（View.java:18794）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5951）在android.widget.FrameLayout.onMeasure（FrameLayout.java:194）在android.support.v7.widget.ContentFrameLayout.onMeasure（ContentFrameLayout.java:135）在android.view.View.measure（View.java:18794）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5951）在android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1465）在android.widget.LinearLayout.measureVertical（LinearLayout.java:748）在android.widget.LinearLayout.onMeasure（LinearLayout.java:630）在android.view.View.measure（View.java:18794）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5951）在android.widget.FrameLayout.onMeasure（FrameLayout.java:194）在android.view.View.measure（View.java:18794）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5951）在android.widget.LinearLayout.measureChildBeforeLayout（LinearLayout.java:1465）在android.widget.LinearLayout.measureVertical（LinearLayout.java:748）在android.widget.LinearLayout.onMeasure（LinearLayout.java:630）在android.view.View.measure（View.java:18794）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:5951）在android.widget.FrameLayout.onMeasure（FrameLayout.java:194）在com.android.internal.policy.PhoneWindow $ DecorView.onMeasure（PhoneWindow.java:2643）在android.view.View.measure（View.java:18794）在android.view.ViewRootImpl.performMeasure（ViewRootImpl.java:2100）在android.view.ViewRootImpl.measureHierarchy（ViewRootImpl.java:1216）在android.view.ViewRootImpl.performTraversals（ViewRootImpl.java:1452）在android.view.ViewRootImpl.doTraversal（ViewRootImpl.java:1107）在android.view.ViewRootImpl $ TraversalRunnable.run（ViewRootImpl.java:6013）在android.view.Choreographer $ CallbackRecord.run（Choreographer.java:858）在android.view.Choreographer.doCallbacks（Choreographer.java:670）在android.view.Choreographer.doFrame（Choreographer.java:606）在android.view.Choreographer $ FrameDisplayEventReceiver.run（Choreographer.java:844）在android.os.Handler.handleCallback（Handler.java:739）在android.os.Handler.dispatchMessage（Handler.java:95）在android.os.Looper.loop（Looper.java:148）在android.app.ActivityThread.main（ActivityThread.java:5417） at java.lang.reflect.Method.invoke（Native Method）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:726）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:616）

ACRA初始化是否会影响Volley，以便Volley没有正确启动以抛出NullPointerException？可以解决这个问题的原因是什么？

Answer 1

mInstance是null，因为您从不为其分配值。这与ACRA无关，除非您在ACRA中添加时意外删除了一些代码。

启动ACRA导致排球的其他问题，可能的修复？

1 个答案: