Android Image loader library with support for ETags, If-Modi

Question

我已经使用Android Http图像管理器一段时间了，最近我切换到Android Universal Image Loader

恐怕它们都不支持验证本地缓存是否是最新的。

我目前正在寻找的是一个图像加载器库，具有社区支持和支持通过 ETag 和/或 If-Modified-Since 检查远程更改

Answer 1

问题由 Github AUIL 问题跟踪器回答。谢谢诺斯特拉

https://github.com/nostra13/Android-Universal-Image-Loader/issues/75

public class URLConnectionImageDownloader extends ImageDownloader {
    @Override
    public InputStream getStreamFromNetwork(URI imageUri) throws IOException {
        URLConnection conn = imageUri.toURL().openConnection();
        // check etag/last-modification-date/... params
        // if image was changed then we should delete cached image from memory cache and disc cache
        // Delete image from caches
        String uri = imageUri.toString();
        File imageFile = ImageLoader.getDiscCache().get(uri)
        if (imageFile.exists()) {
            imageFile.delete();
        }
        MemoryCacheAware<String, Bitmap memoryCache = ImageLoader.getMemoryCache();
        for (String cacheKey : memoryCache.keys()) {
            if (cacheKey.contains(uri) {
                memoryCache.remove(cacheKey);
            }
        }

        return new FlushedInputStream(new BufferedInputStream(conn.getInputStream()));
    }
}