解決一個因Bitmap引起的OOM問題

BitmapFactory.decodeStream引起了OutOfMemory. 在decodeStream之前，通過設定options.inJustDecodeBounds = true;讓Bitmap實作虛加載。

public class PhotoViewFragment extends Fragment {

    private PhotoView mGestureImageView;
    private Bitmap mBitmap;

    @Override
    public View onCreateView(LayoutInflater inflater, final ViewGroup container, Bundle savedInstanceState) {
        View inflateView = inflater.inflate(R.layout.fragment_photo_view_show, container, false);
        mGestureImageView = (PhotoView) inflateView.findViewById(R.id.p_w_picpath_turn_show_gestureImageView);
        getBundleData();
        try {
            /*減少記憶體占用*/
            BitmapFactory.Options opt = new BitmapFactory.Options();
            opt.inPreferredConfig = Bitmap.Config.RGB_565;
            opt.inPurgeable = true;
            opt.inInputShareable = true;
            opt.inJustDecodeBounds = true;//虛加載

            FileInputStream fis = new FileInputStream(Environment.getExternalStorageDirectory() + File.separator + "abc.png");
            mBitmap = BitmapFactory.decodeStream(fis, null, opt);

            int width = opt.outWidth;
            int height = opt.outHeight;

            if (height / width >= 1.6) {//判斷橫豎圖
                mGestureImageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            } else {
                mGestureImageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
            }

            DisplayImageOptions op = new DisplayImageOptions.Builder()
                    .cacheInMemory(true) // default
                    .build();
            Uri uri = Uri.fromFile(new File(Environment.getExternalStorageDirectory() + File.separator + "abc.png"));
            ImageLoader.getInstance().displayImage(uri.toString(), mGestureImageView, op);
        } catch (Exception e) {
            Log.e("Fragment", "onCreateView p_w_picpath-view", e);
        }
        return inflateView;
    }

    /**
     * 重置GestureImageView為原大小
     */
    public void resetGestureImageView() {
        mGestureImageView.reset();
    }

    /**
     * 獲得Bundle
     */
    private void getBundleData() {
        Bundle bundle = getArguments();
    }

    @Override
    public void onPause() {
        super.onPause();
        mGestureImageView.reset();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mBitmap != null && !mBitmap.isRecycled()) {
            mBitmap.recycle();
            mBitmap = null;
        }
    }


}