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Initialising the cache

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The Lru Cache will store all the added resources (values) for fast access until it reaches a memory limit, in which case it will drop the less used resource (value) to store the new one.

To initialise the Lru cache you need to provide a maximum memory value. This value depends on your application requirements and in how critical the resource is to keep a smooth app usage. A recommended value for an image gallery, for example, would be 1/8 of your maximum available memory.

Also note that the Lru Cache works on a key-value basis. In the following example, the key is a String and the value is a Bitmap: 

int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
int cacheSize = maxMemory / 8;

LruCache<String, Bitmap> = memoryCache = new LruCache<String, Bitmap>(cacheSize) {
    protected int sizeOf(String key, Bitmap bitmap) {
        return bitmap.getByteCount();
    }
};
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LruCache:
* LruCache
* Adding a BitmapResource to the cache
* Initialising the cache
* Getting a BitmapResouce from the cache
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