android - 如果我选择大图像，OnActivityResult 会崩溃

Question

我必须获取图库中图像的图像路径，以将其保存到列表中，不幸的是，如果所选图像太大，则以下代码会使应用程序崩溃(并且无法查看我的 try catch block 中的警报) .

private void openImage() {

         try{
            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.setType("image/*");
            startActivityForResult(i, FILE_REQ_CODE);
            } catch (RuntimeException e) {
                           e.printStackTrace();
               Alerts.TooLargeImage(LoadImage.this);
            }

    }

    protected void onActivityResult(int requestCode, int resultCode,
            Intent intentData) {
        try{
            Uri tmp = intentData.getData();
            String path = tmp.toString();
            imagePathList.add(path);
            preview.setImageURI(tmp);
            FileArchiveManager.saveImagePath(imagePathList);
            super.onActivityResult(requestCode, resultCode, intentData);
            } catch (RuntimeException e) {
                           e.printStackTrace();
               Alerts.TooLargeImage(LoadImage.this);
            }
    }

错误日志

java.lang.OutOfMemoryError: bitmap size exceeds VM budget(Heap Size=8135KB, Allocated=3718KB, Bitmap Size=11707KB)
    at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
    at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:694)
    at android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:494)
    at android.graphics.drawable.Drawable.createFromResourceStream(Drawable.java:697)
    at android.graphics.drawable.Drawable.createFromStream(Drawable.java:657)
    at android.widget.ImageView.resolveUri(ImageView.java:592)
    at android.widget.ImageView.setImageURI(ImageView.java:313)
    at com.myapp.LoadImage.onActivityResult(LoadImage.java:131)
    at android.app.Activity.dispatchActivityResult(Activity.java:4108)
    at android.app.ActivityThread.deliverResults(ActivityThread.java:3016)
    at android.app.ActivityThread.handleSendResult(ActivityThread.java:3072)
    at android.app.ActivityThread.access$2000(ActivityThread.java:135)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1084)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:150)
    at android.app.ActivityThread.main(ActivityThread.java:4385)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607)
    at dalvik.system.NativeStart.main(Native Method)

如何解决这个问题？

Answer 1

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

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
    int reqWidth, int reqHeight) {

    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(res, resId, options);

    // Calculate inSampleSize
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(res, resId, options);
}

mImageView.setImageBitmap(decodeSampledBitmapFromResource(getResources(), R.id.myimage, 100, 100));

使用 BitmapFactory.decodeResource() 和 BitmapFactory.Options.inSampleSize 将允许您将位图的下采样版本加载到 RAM 中(因为您实际上不需要要显示这么大的图像)而不会导致 java.lang.OutofMemoryError。