com.example.android.foodrecipes.app.utils.LruBitmapCache.java Source code

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Here is the source code for com.example.android.foodrecipes.app.utils.LruBitmapCache.java

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/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.example.android.foodrecipes.app.utils;

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

import com.android.volley.toolbox.ImageLoader.ImageCache;

/**
 * Implementation of LRU-based {@link ImageCache} for {@code ImageLoader} from the {@code Volley}
 * library.
 *
 * @author Andrei Safronov
 */
public class LruBitmapCache extends LruCache<String, Bitmap> implements ImageCache {

    public LruBitmapCache(Context context) {
        super(getDefaultCacheSize(context));
    }

    @Override
    protected int sizeOf(String key, Bitmap value) {
        return value.getRowBytes() * value.getHeight();
    }

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

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

    /**
     * Returns the cache size which fits roughly 3 screens of images
     *
     * @param ctx Context to get access to resources
     * @return the cache size which fits roughly 3 screens of images
     */
    public static int getDefaultCacheSize(Context ctx) {
        DisplayMetrics displayMetrics = ctx.getResources().getDisplayMetrics();
        int screen = displayMetrics.widthPixels * displayMetrics.heightPixels * 4; //4 bytes per px
        return screen * 3; //3 screens
    }
}