Android-无法使用json和Picasso将图片从url下载到外部存储

Question

My app function is something like i want have displayed several image from Json to custom adapter using volley and now what I need is to download all displayed image on that particular fragment to external memory when user click on download button.

I have given permission to manifest file:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

code for extracting image and downloading using picasso is :

public class AKVSeriesOneFragment extends Fragment {
private static final String TAG = MainActivity.class.getSimpleName();
private View view;
// Movies json url
private static final String url = "https://developers.kurtisgallery.in/example_api/kurtisone/id/8";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private GridView gridView;
private CustomListAdapter adapter;


public AKVSeriesOneFragment() {
    // Required empty public constructor
}


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




}

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


    // Inflate the layout for this fragment
    View rootView = inflater.inflate(R.layout.fragment_akvseries_one, container, false);
    ImageView imageView = (ImageView) rootView.findViewById(R.id.downoadimgs);

    imageView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {


            for (int i = 0; i < movieList.size(); i++) {

                String url = movieList.get(i).getThumbnailUrl();
                Picasso.with(getContext())
                        .load(url)
                        .into(new Target() {
                            @Override
                            public void onBitmapLoaded(final Bitmap bitmap, Picasso.LoadedFrom from) {

                                new Thread(new Runnable() {
                                    @Override
                                    public void run() {

                                        File sd = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
                                        File folder = new File(sd, "/Picasso/");
                                        if (!folder.exists()) {
                                            if (!folder.mkdir()) {
                                                Log.e("ERROR", "Cannot create a directory!");
                                            } else {
                                                folder.mkdir();
                                            }
                                        }




                                        for (int i=0; i< movieList.size(); i++) {

                                            File[] fileName = {new File("Image"+i)};

                                            if (!fileName[i].exists()) {
                                                try {
                                                    fileName[i].createNewFile();
                                                } catch (IOException e) {
                                                    e.printStackTrace();
                                                }
                                            } else {

                                                try {
                                                    FileOutputStream outputStream = new FileOutputStream(String.valueOf(fileName[i]));
                                                    bitmap.compress(Bitmap.CompressFormat.JPEG, 100, outputStream);
                                                    outputStream.close();

                                                } catch (IOException e) {
                                                    e.printStackTrace();
                                                }
                                            }

                                        }

                                    }
                                }).start();

                            }

                            @Override
                            public void onBitmapFailed(Drawable errorDrawable) {

                            }

                            @Override
                            public void onPrepareLoad(Drawable placeHolderDrawable) {

                            }
                        });
            }



        }
    });

    gridView = (GridView) rootView.findViewById(R.id.list);
    adapter = new CustomListAdapter(getActivity(), movieList);
    gridView.setAdapter(adapter);

    pDialog = new ProgressDialog(getActivity());
    // Showing progress dialog before making http request
    pDialog.setMessage("Loading...");
    pDialog.show();

    JsonArrayRequest movieReq = new JsonArrayRequest(url,
            new Response.Listener<JSONArray>() {
                @Override
                public void onResponse(JSONArray response) {
                    Log.d(TAG, response.toString());
                    hidePDialog();

                    // Parsing json
                    for (int i = 0; i < response.length(); i++) {
                        try {

                            JSONObject obj = response.getJSONObject(i);
                            Movie movie = new Movie();
                            //movie.setTitle(obj.getString("category_name"));
                            movie.setThumbnailUrl(obj.getString("thumb_img_dest"));
                     movieList.add(movie);

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

                    }

                    // notifying list adapter about data changes
                    // so that it renders the list view with updated data
                    adapter.notifyDataSetChanged();
                }
            }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            VolleyLog.d(TAG, "Error: " + error.getMessage());
            hidePDialog();

        }
    });

    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(movieReq);

    return  rootView;
}

Here I am getting error EROFS (Read-only file system) I have searched stackoverflow before and found many similar probleb but non of solution is working for me.As I am beginner android developer.

Answer 1

I solved my problem, as code was correct but problem arose due to permission on mashmallow. So I did this code:

    private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
        Manifest.permission.READ_EXTERNAL_STORAGE,
        Manifest.permission.WRITE_EXTERNAL_STORAGE
};

//persmission method.
public static void verifyStoragePermissions(Activity activity) {
    // Check if we have read or write permission
    int writePermission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
    int readPermission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.READ_EXTERNAL_STORAGE);

    if (writePermission != PackageManager.PERMISSION_GRANTED || readPermission != PackageManager.PERMISSION_GRANTED) {
        // We don't have permission so prompt the user
        ActivityCompat.requestPermissions(
                activity,
                PERMISSIONS_STORAGE,
                REQUEST_EXTERNAL_STORAGE
        );
    }
}

and in activity file i call the function

verifyStoragePermissions(this);

Hope it help someone!!