How to Force a Cache Clearing Using Universal Image Loader Android

android universal image loader clear cache

You can use DiskCacheUtils and MemoryCacheUtils to remove specific image by image url

DiskCacheUtils.removeFromCache(imageUrl, ImageLoader.getInstance().getDiskCache());    
MemoryCacheUtils.removeFromCache(imageUrl, ImageLoader.getInstance().getMemoryCache());

or to completely clean cache

ImageLoader.getInstance().clearMemoryCache()
ImageLoader.getInstance().clearDiskCache()

To clear cache when activity created you can call this methods after you initialized your ImageLoader

To clear cache on leaving the activity you can call methods in onDestroy () , but i should mind that system can kill your activity without calling this method.

Universal Image Loader: Can I use cache but also refresh it?

So in the end I used an ImageLoadingListener as follows:

onLoadingStarted:
Check for cache when loading starts.

onLoadingComplete:
If no cache was found then do nothing. The request will be sent to network and cache will be updated naturally.
Otherwise clear cache and call displayImage again (no listener needed this time). The cached image will be shown in the view normally. Moreover, when the 2nd loading finishes, view and cache will be updated.

ImageLoader.getInstance().displayImage(imageUri, view, new SimpleImageLoadingListener() {
            boolean cacheFound;

            @Override
            public void onLoadingStarted(String url, View view) {
                List<String> memCache = MemoryCacheUtils.findCacheKeysForImageUri(url, ImageLoader.getInstance().getMemoryCache());
                cacheFound = !memCache.isEmpty();
                if (!cacheFound) {
                    File discCache = DiscCacheUtils.findInCache(url, ImageLoader.getInstance().getDiscCache());
                    if (discCache != null) {
                        cacheFound = discCache.exists();
                    }
                }
            }

            @Override
            public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
                if (cacheFound) {
                    MemoryCacheUtils.removeFromCache(imageUri, ImageLoader.getInstance().getMemoryCache());
                    DiscCacheUtils.removeFromCache(imageUri, ImageLoader.getInstance().getDiscCache());    
                    ImageLoader.getInstance().displayImage(imageUri, (ImageView) view);
                }
            }
        });
    }

How To Use universal image loader offline caching?

You can use the ImageLoaderConfiguration.Builder class to customize disk caching. This includes the methods:

• diskCacheExtraOptions()
• diskCacheSize() (in bytes).
• diskCacheFileCount()
• diskCacheFileNameGenerator()
• and some others.

Or you can just use diskCache(DiskCache) to provide a custom class for implementing offline caching.

From the example in the Configuration section of the wiki:

File cacheDir = StorageUtils.getCacheDirectory(context);
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(context)
    .memoryCacheExtraOptions(480, 800) // default = device screen dimensions
    .diskCacheExtraOptions(480, 800, null)
    .taskExecutor(...)
    .taskExecutorForCachedImages(...)
    .threadPoolSize(3) // default
    .threadPriority(Thread.NORM_PRIORITY - 1) // default
    .tasksProcessingOrder(QueueProcessingType.FIFO) // default
    .denyCacheImageMultipleSizesInMemory()
    .memoryCache(new LruMemoryCache(2 * 1024 * 1024))
    .memoryCacheSize(2 * 1024 * 1024)
    .memoryCacheSizePercentage(13) // default
    .diskCache(new UnlimitedDiscCache(cacheDir)) // default
    .diskCacheSize(50 * 1024 * 1024)
    .diskCacheFileCount(100)
    .diskCacheFileNameGenerator(new HashCodeFileNameGenerator()) // default
    .imageDownloader(new BaseImageDownloader(context)) // default
    .imageDecoder(new BaseImageDecoder()) // default
    .defaultDisplayImageOptions(DisplayImageOptions.createSimple()) // default
    .writeDebugLogs()
    .build();

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