Android - 从图库/相机获取图像时，Dialog不会刷新ImageView

Question

So i´m working on an app in which I need to show a dialog, and inside this dialog, the user can press a button to select an image from the gallery or take a photo from the camera and display that image on an ImageView inside a dialog´s ImageView. I´m able to take the photo from the camera/gallery, and then i use it as the ImageView image, but it doesn´t show it until i press the button again, as if the layout had to be refreshed. This is my code:

To call the dialog (get_permissions(); is used on Android M for getting the write and read storage permissions, this works correctly)

protected void createDialog() {
        final Dialog dialog = new Dialog(WeightActivity.this, android.R.style.Theme_Material_Light_Dialog_Alert);
        dialog.getWindow();
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
        dialog.setContentView(R.layout.dialog_add_weight);

        Button okButton = (Button) dialog.findViewById(R.id.okButton);
        final ImageButton selectImageButton = (ImageButton) dialog.findViewById(R.id.selectImageButton);
        final ImageView imageView = (ImageView) dialog.findViewById(R.id.imageView);

        selectImageButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
            get_permissions();
            selectImage();
            imageView.setImageBitmap(bm);
            }
        });

        dialog.show();
    }

private void selectImage() {
    final String[] items = WeightActivity.this.getResources().getStringArray(R.array.photo_options);
    AlertDialog.Builder builder = new AlertDialog.Builder(WeightActivity.this);
    builder.setTitle(R.string.weight_dialog_add_photo);
    builder.setItems(items, new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int item) {
            if (items[item].equals(items[0])) {
                Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(intent, REQUEST_CAMERA);
            } else if (items[item].equals(items[1])) {
                Intent intent = new Intent(
                        Intent.ACTION_PICK,
                        android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                intent.setType("image/*");
                startActivityForResult(
                        Intent.createChooser(intent, "Select File"),
                        SELECT_FILE);
            }
        }
    });
    builder.show();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == RESULT_OK) {
        if (requestCode == REQUEST_CAMERA) {
            bm = (Bitmap) data.getExtras().get("data");
        } else if (requestCode == SELECT_FILE) {
            Uri selectedImageUri = data.getData();
            String[] projection = {MediaStore.MediaColumns.DATA};
            CursorLoader cursorLoader = new CursorLoader(this, selectedImageUri, projection, null, null,
                    null);
            Cursor cursor = cursorLoader.loadInBackground();
            int column_index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DATA);
            cursor.moveToFirst();
            String selectedImagePath = cursor.getString(column_index);
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;
            BitmapFactory.decodeFile(selectedImagePath, options);
            options.inJustDecodeBounds = false;
            bm = BitmapFactory.decodeFile(selectedImagePath, options);
        }
    }
}

Could somebody help me please?? Thanks a lot!

Answer 1

The problem is this,

get_permissions();
selectImage();
imageView.setImageBitmap(bm);

selectImage() starts the activity, but it doesn't block; it returns immediately. You then call setImageBitmap() , probably on a null valued bm instance field.

Move, or otherwise trigger the imageView.setImageBitmap() call in onActivityResult() , only after you have decoded the image.