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androidlistviewnetworkimageview

NetworkImageView crashing

My app has an activity with a ListView, and for each cell in the list, I need to load an image from an URL. However, the app crashes when I add the line to load the image.

I don't know if the error is caused by my code or some cell-reuse-behavior of the List View, since the Logcat does not point to any line in my code. I made sure that the URLs passed are correct and may not interfere.

I followed this tutorial to write this code.

Here's the ListView adapter class, where I load the imagem on getView(...):

class CellAdapter extends BaseAdapter {

    Context context;
    List<Product> productList;
    private static LayoutInflater inflater = null;

    public CellAdapter(Context context, List<Product> productList) {
        this.context = context;
        this.productList = productList;
        inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public int getCount() {
        return productList.size();
    }

    @Override
    public Product getItem(int position) {
        return productList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View view = convertView;
        while (view == null)
            view = inflater.inflate(R.layout.product_result, null);

        NetworkImageView image = (NetworkImageView) view.findViewById(R.id.cell_product_image);
        image.setDefaultImageResId(R.drawable.image_placeholder);
        image.setImageUrl(getItem(position).imageURL, APIManager.getSharedImageLoader());

        return view;
    }
}

The ImageLoader used above is set up as follows:

sharedImageLoader = new ImageLoader(Volley.newRequestQueue(context), new BitmapLruCache());

And the BitmapLruCache is:

public class BitmapLruCache extends LruCache<String, Bitmap> implements ImageLoader.ImageCache {

    public BitmapLruCache() {
        this(getDefaultLruCacheSize());
    }

    public BitmapLruCache(int sizeInKiloBytes) {
        super(sizeInKiloBytes);
    }

    @Override
    protected int sizeOf(String key, Bitmap value) {
        return value.getRowBytes() * value.getHeight() / 1024;
    }

    @Override
    public Bitmap getBitmap(String url) {
        return get(url);
    }

    @Override
    public void putBitmap(String url, Bitmap bitmap) {
        put(url, bitmap);
    }

    public static int getDefaultLruCacheSize() {
        final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);

        return maxMemory / 8;
    }
}

This is the Logcat error:

E/AndroidRuntime﹕ FATAL EXCEPTION: main
    java.lang.NullPointerException
            at com.android.volley.Request.<init>(Request.java:137)
            at com.android.volley.toolbox.ImageRequest.<init>(ImageRequest.java:71)
            at com.android.volley.toolbox.ImageLoader.get(ImageLoader.java:219)
            at com.android.volley.toolbox.NetworkImageView.loadImageIfNecessary(NetworkImageView.java:149)
            at com.android.volley.toolbox.NetworkImageView.onLayout(NetworkImageView.java:198)
            at android.view.View.layout(View.java:7175)
            at android.widget.RelativeLayout.onLayout(RelativeLayout.java:912)
            at android.view.View.layout(View.java:7175)
            at android.widget.ListView.setupChild(ListView.java:1833)
            at android.widget.ListView.makeAndAddView(ListView.java:1748)
            at android.widget.ListView.fillDown(ListView.java:670)
            at android.widget.ListView.fillFromTop(ListView.java:727)
            at android.widget.ListView.layoutChildren(ListView.java:1598)
            at android.widget.AbsListView.onLayout(AbsListView.java:1262)
            at android.view.View.layout(View.java:7175)
            at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1254)
            at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1130)
            at android.widget.LinearLayout.onLayout(LinearLayout.java:1047)
            at android.view.View.layout(View.java:7175)
            at android.widget.FrameLayout.onLayout(FrameLayout.java:343)
            at android.view.View.layout(View.java:7175)
            at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1254)
            at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1130)
            at android.widget.LinearLayout.onLayout(LinearLayout.java:1047)
            at android.view.View.layout(View.java:7175)
            at android.widget.FrameLayout.onLayout(FrameLayout.java:343)
            at android.view.View.layout(View.java:7175)
            at android.widget.FrameLayout.onLayout(FrameLayout.java:343)
            at android.view.View.layout(View.java:7175)
            at android.view.ViewRoot.performTraversals(ViewRoot.java:1140)
            at android.view.ViewRoot.handleMessage(ViewRoot.java:1859)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:130)
            at android.app.ActivityThread.main(ActivityThread.java:3714)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:507)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:853)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611)
            at dalvik.system.NativeStart.main(Native Method)

Here is the method containing the null pointer exception:

    public Request(int method, String url, Response.ErrorListener listener) {
        mMethod = method;
        mUrl = url;
        mErrorListener = listener;
        setRetryPolicy(new DefaultRetryPolicy());
        /* the next line is line 137 with the Exception */
        mDefaultTrafficStatsTag = TextUtils.isEmpty(url) ? 0: Uri.parse(url).getHost().hashCode(); 
    }
Solution

  • You are using an out-of-date version of this library, which is missing the following two recent commits:

    6c33917 Merge "Guard against NullPointerException currently occurring in Volley when a Request is given a url whose host is null." by Ficus Kirkpatrick - 3 weeks ago idea133-weekly-release master

    0ec9297 Guard against NullPointerException currently occurring in Volley when a Request is given a url whose host is null. by kang - 3 weeks ago

    Update your working version with git to reflect the current state of the project repository and you should be fine. Examining the diff for these, the change is basically adding and handling null checking.