android - 位图 decodeStream OutOfMemory 异常

Question

我在我的应用程序中使用我自己的 Android ViewFlow 示例实现。我正在从网络服务下载加密图像，而不是将它们保存在 SD 卡上。我正在使用 viewflow 即时解密图像并显示它们。但问题是，当用户开始过快地更改图像时，它会向我抛出 OutOfMemoryException 并且我发现/测试的所有信息都不适用于我的情况。这是我正在使用的:

 @Override
public View getView(int position, View convertView, ViewGroup parent) {
    if (convertView == null) {
        convertView = mInflater.inflate(R.layout.image_item, null);
    }

    try {
        File bufferFile = new File(ids.get(position));
        FileInputStream fis   = new FileInputStream(bufferFile);

        Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
        SecretKeySpec keySpec = new SecretKeySpec("01234567890abcde".getBytes(), "AES");
        IvParameterSpec ivSpec = new IvParameterSpec("fedcba9876543210".getBytes());
        cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
        CipherInputStream cis = new CipherInputStream(fis, cipher);

        BitmapFactory.Options o = new BitmapFactory.Options();
        final int REQUIRED_SIZE=300*1024;

        //Find the correct scale value. It should be the power of 2.
        int width_tmp= o.outWidth, height_tmp= o.outHeight;
        int scale=1;
        while(true){
            if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
                break;
            width_tmp/=2;
            height_tmp/=2;
            scale*=2;
        }

        //Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize=scale;

        Bitmap ops = BitmapFactory.decodeStream(cis,null,o2);
        ((ImageView) convertView.findViewById(R.id.imgView)).setImageBitmap(ops);
        cis.close();
        fis.close();

        System.gc();

    } catch (Exception e) {
        e.printStackTrace();
        ((ImageView) convertView.findViewById(R.id.imgView)).setImageResource(R.drawable.image_unavailablee);
    }

    return convertView;
}

它仍然在线抛出异常:

((ImageView) convertView.findViewById(R.id.imgView)).setImageBitmap(ops);

除了这个异常(exception):

java.lang.OutOfMemoryError: bitmap size exceeds VM budget(Heap Size=6791KB, Allocated=3861KB, Bitmap Size=26006KB)

有什么解决办法吗？

Answer 1

仅供处理大型位图的任何人引用，有一篇文章展示了如何最好地处理此类问题以避免内存不足!

http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

希望对您有所帮助!