Question

我试图使用volley libs下载片段中的图像。但我无法修复错误：

＆＃13;

public static class ViewFragment extends Fragment {

        ImageLoader mImageLoader;
        NetworkImageView mNetworkImageView;
        private static String IMAGE_URL =
                "http://meteo.profi-net.sk/webcams/BIELAPUT-l.jpg";

        public ViewFragment() {
            // Required empty public constructor
        }

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            // Get the NetworkImageView that will display the image.
            mNetworkImageView = (NetworkImageView) getView().findViewById(R.id.networkImageView);

            // Get the ImageLoader through your singleton class.
            mImageLoader = VolleySingleton.getInstance(this).getImageLoader();  //!!!!!! HERE IS THE ERROR

            // Set the URL of the image that should be loaded into this view, and
            // specify the ImageLoader that will be used to make the request.
            mNetworkImageView.setImageUrl(IMAGE_URL, mImageLoader);

        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // Inflate the layout for this fragment
            return inflater.inflate(R.layout.fragment_camera_view, container, false);
        }


    }

＆＃13;

getInstance（this）标记为错误，但我不知道如何更改它。如果我在某些活动中编写完全相同的代码，那就更难了。

有人可以解释一下如何在片段中使用NetworkImageView吗？

Answer 1

getInstance需要一个Context作为参数，Fragment不是，而Activity是。片段可以通过调用getActivity方法来访问其保持活动。您应该在每次调用之前检查该片段是否仍附加到其活动，否则您将崩溃

所以你可以这样做：

if(isAdded())
{
            .......... your code ..............
            // Get the ImageLoader through your singleton class.
            mImageLoader = VolleySingleton.getInstance(getActivity()).getImageLoader();
                .......... your code ..............
}

在片段中使用NetworkImageView - androidstudio

1 个答案: