How to reload NetworkImageView

Question

I have an app which is displaying fragment with one NetworkImageView widget from android Volley.

The image at URL which is loaded in NetworkImageView is changing every 5 secounds so I want to uptade this image by pressing reload button that I have created in action bar.

I have found 2 problems:

1. If I call this code for loading Image again(it was already called when the fragment was created at onActivityCreated() method):

   mNetworkImageView = (NetworkImageView) getView().findViewById(R.id.networkImageView);
   mImageLoader = VolleySingleton.getInstance(getActivity()).getImageLoader();
   mNetworkImageView.setImageUrl(IMAGE_URL, mImageLoader);
   

so nothing will happens(it is not the actual IMG of that link), I think its because it is now loading IMG from cache and not from internet.

2. If I call fragment reload() method:

   public void reload(){
   
   MainActivity activity = (MainActivity) getActivity();
   IMAGE_URL = activity.getMyData();
   
   mNetworkImageView = (NetworkImageView) getView().findViewById(R.id.networkImageView);
   
   mImageLoader = VolleySingleton.getInstance(getActivity()).getImageLoader();
   
   mNetworkImageView.setImageUrl(IMAGE_URL, mImageLoader);
   

from MainActivity:

public boolean onOptionsItemSelected(MenuItem item) {        
    int id = item.getItemId();

    if (id == R.id.action_settings) {
        return true;
    }

    if (id == R.id.action_reload) {
        ViewFragment fragment = new ViewFragment();
        fragment.reload();
    }

    return super.onOptionsItemSelected(item);
}

app get NullPointerException error after clicking action bar reload button.

the reload(); method is the place where I would like to reload NetworkImageView.

Can someone explain me pls how to correct this issues?

Answer 1

First get the cache from request queue.

Then remove your URL from the cache by calling remove function from the cache ( the key is your url).

then use your first approach:

mNetworkImageView = (NetworkImageView) getView().findViewById(R.id.networkImageView);
mImageLoader = VolleySingleton.getInstance(getActivity()).getImageLoader();
mNetworkImageView.setImageUrl(IMAGE_URL, mImageLoader);