LruCacheの使い方

ImageCache.java

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

public final class ImageCache {

    private static final int MEM_CACHE_SIZE = 1 * 1024 * 1024; // 1MB

    private static LruCache<String, Bitmap> sLruCache;

    static {
        sLruCache = new LruCache<String, Bitmap>(MEM_CACHE_SIZE) {
            @Override
            protected int sizeOf(String key, Bitmap bitmap) {
                return bitmap.getRowBytes() * bitmap.getHeight();
            }
        };
    }

    private ImageCache() {
    }

    public static void setImage(String key, Bitmap bitmap) {
        if (getImage(key) == null) {
            sLruCache.put(key, bitmap);
        }
    }

    public static Bitmap getImage(String key) {
        return sLruCache.get(key);
    }
}