metu.life-android/app/src/main/java/com/keylesspalace/tusky/VolleySingleton.java

package com.keylesspalace.tusky;

import android.content.Context;
import android.graphics.Bitmap;
import android.support.v4.util.LruCache;

import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.Volley;

public class VolleySingleton {
    private static VolleySingleton instance;
    private RequestQueue requestQueue;
    private ImageLoader imageLoader;
    private static Context context;

    private VolleySingleton(Context context) {
        VolleySingleton.context = context;
        requestQueue = getRequestQueue();
        imageLoader = new ImageLoader(requestQueue,
                new ImageLoader.ImageCache() {
                    private final LruCache<String, Bitmap> cache = new LruCache<>(20);

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

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

    public static synchronized VolleySingleton getInstance(Context context) {
        if (instance == null) {
            instance = new VolleySingleton(context);
        }
        return instance;
    }

    public RequestQueue getRequestQueue() {
        if (requestQueue == null) {
            /* getApplicationContext() is key, it keeps you from leaking the
             * Activity or BroadcastReceiver if someone passes one in. */
            requestQueue= Volley.newRequestQueue(context.getApplicationContext());
        }
        return requestQueue;
    }

    public <T> void addToRequestQueue(Request<T> request) {
        getRequestQueue().add(request);
    }

    public ImageLoader getImageLoader() {
        return imageLoader;
    }
}