Android - Picasso - Retry with a different network policy

Question

I'm using the following code to load an URL to an ImageView. It first tries to load from cache, and if it fails it tries to fetch it from internet:

Picasso.with(getActivity())
.load(imageUrl)
.networkPolicy(NetworkPolicy.OFFLINE)
.into(imageView, new Callback() {
    @Override
    public void onSuccess() {

    }

    @Override
    public void onError() {
        //Try again online if cache failed
        Picasso.with(getActivity())
                .load(imageUrl)
                .error(R.drawable.error_image)
                .into(imageView, new Callback() {
            @Override
            public void onSuccess() {

            }

            @Override
            public void onError() {
                Log.v("Picasso","Could not fetch image");
            }
        });
    }
});

It works just fine, but the problem is that is really cumbersome to write all this code every time I have to load an image, compared to the standard:

Picasso.with(getContext())
 .load(imageUrl)
 .into(imageView);

Is there a way to encapsulate this behaviour ? Does Picasso provide any way to help it?

If you're always going to retry, why are you trying with `OFFLINE` in the first place? It'll use the cached version if available by default. — ianhanniballake, Dec 14 '16 at 19:19
@ianhanniballake I didn't know that. I was using this answer http://stackoverflow.com/a/30686992/2271834 and so I assumed that cache usage was explicit — FlyingPumba, Dec 14 '16 at 19:26

score 1 · Answer 1 · answered Jun 07 '17 at 11:38

try using this code this worked for me

this class uses a retry policy to download images

public class PicassoHelper {

private static final boolean isDebug = false;
private static final int MAX_RETRY_TIME = 10;         // Default is 3 in Picasso
private static final int MAX_DOWNLOADING_THREAD = 4;  // Recommand in Volley , it is 4
private static Picasso sPicasso;

public static Picasso Pwith(Context context) {
    // Mimicking Picasso's new OkHttpLoader(context), but with our custom OkHttpClient
    if (sPicasso == null) {
        OkHttpClient client = new OkHttpClient();
        client.setRetryOnConnectionFailure(true);
        // Create A Retry Policy
        client.interceptors().add(new Interceptor() {
            @Override
            public Response intercept(Interceptor.Chain chain) throws IOException {
                Request request = chain.request();
                // try the request
                Response response = chain.proceed(request);
                int tryCount = 0;
                while (!response.isSuccessful() && tryCount < MAX_RETRY_TIME) {
                    Log.d("intercept :"," Request is not successful - " + tryCount);
                    tryCount++;
                    // retry the request
                    response = chain.proceed(request);
                }
                // otherwise just pass the original response on
                return response;
            }
        });
        sPicasso = new Picasso.Builder(context)
                .executor(Executors.newFixedThreadPool(MAX_DOWNLOADING_THREAD))
                .downloader(new OkHttpDownloader(client)).build();
        if(isDebug) {
            sPicasso.setIndicatorsEnabled(true);
            sPicasso.setLoggingEnabled(true);
        }
    }
    return sPicasso;
}

}

Now after creating the class its time to use it in out code

PicassoHelper.Pwith(application_context).load(image_url).into(imageView);

score 0 · Accepted Answer · edited May 23 '17 at 12:08

@ianhanniballake comment was right, and this SO answer is misleading. To enable caching, you only have to add to your Application:

Picasso.Builder builder = new Picasso.Builder(this);
builder.downloader(new OkHttpDownloader(this, Integer.MAX_VALUE));
Picasso.setSingletonInstance(builder.build());

And then Picasso/OkHttp takes care of looking in the cache before it tries to load an image from internet.

Android - Picasso - Retry with a different network policy

2 Answers2