缓存列表视图的图片

Question

所以我有一个包含来自某些网址的图像的列表视图，我尝试在加载位图数组列表后保存图片，但最终我的设备上的列表中仅显示 2-3 张图片（模拟器显示所有图片），所以我下载后尝试缓存图片，我使用： `

     for (int i = 0; i < url.length; i++){
            URL urlAdress = new URL(url[i]);
            HttpURLConnection conn = (HttpURLConnection) urlAdress
                    .openConnection();
            conn.setDoInput(true);
            conn.connect();
            InputStream is = conn.getInputStream();
            Bitmap bmImg = BitmapFactory.decodeStream(is);

            // picList.add(bmImg);

            File cacheDir = context.getCacheDir();
            File f = new File(cacheDir, "000" + (i + 1));
            FileOutputStream out = null;
            try {
                out = new FileOutputStream(f);
                bmImg.compress(Bitmap.CompressFormat.JPEG, 80, out);
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (out != null)
                        out.close();
                } catch (Exception ex) {
                }
            }
        }

` 将图片保存在缓存中，然后我使用它从适配器中的缓存加载图片：

File cacheDir = context.getCacheDir();
    File f = new File(cacheDir, "000" + position);
    Drawable d = Drawable.createFromPath(f.getAbsolutePath());
    holder.icon.setImageDrawable(d);

但我仍然从 9 中获取 3-4 张图片，这是内存问题吗？ （所有图片加起来有300 kb）

Answer 1

发现问题 Bitmap bmImg = BitmapFactory.decodeStream(is); 有错误并跳过慢速互联网连接上的数据，就像在真实设备上一样，所以我添加

Bitmap bmImg = BitmapFactory.decodeStream(new FlushedInputStream(is));

了

static class FlushedInputStream extends FilterInputStream {
    public FlushedInputStream(InputStream inputStream) {
        super(inputStream);
    }

    @Override
    public long skip(long n) throws IOException {
        long totalBytesSkipped = 0L;
        while (totalBytesSkipped < n) {
            long bytesSkipped = in.skip(n - totalBytesSkipped);
            if (bytesSkipped == 0L) {
                int b = read();
                if (b < 0) {
                    break; // reached EOF
                } else {
                    bytesSkipped = 1; // read one byte
                }
            }
            totalBytesSkipped += bytesSkipped;
        }
        return totalBytesSkipped;
    }
}