Question

Based on code suggestions here at stackoverflow, I’ve tried to extract an image from the MediaStore. However, when I select an actual photo, getContentResolver().query() always returns null. I can’t understand why…

Intent i = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.INTERNAL_CONTENT_URI);
startActivityForResult(i, SELECT_PHOTO);

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    Log.v(TAG,"onActivityResult: requestCode = "+requestCode+", resultCode = "+requestCode);
    if (requestCode == SELECT_PHOTO) {
        Uri selectedImage = data.getData();
        String[] filePathColumn = {android.provider.MediaStore.Images.Media.DATA};
        Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
        if (cursor != null) {
            Log.v(TAG,"onActivityResult: count = "+cursor.getCount());
            if (cursor.getCount() == 1) {
                cursor.moveToFirst();
                int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
                String filePath = cursor.getString(columnIndex);
                Log.v(TAG,"onActivityResult: filePath = "+filePath);
            }
            cursor.close();
        }
    }
}

Answer 1

try restart your emulater or your device(or uninstall/install the SD card)?
somebody tell me the Android System will scan the medias when restart or reload SD card…maybe the database hasn’t change.