为什么在这里我无法将ImageBitmap设置为RelativeLayout？

Question

I'm trying to select a background image from gallery and set it as Activity background. But the problem is here when I set RelativeLayout instead of ImageView , it gives me error on setImageBitmap , what;s the reason here? Here's my code: I referred to this tutorial : http://viralpatel.net/blogs/pick-image-from-galary-android-app/ Thanks in advance!

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK
                && null != data) {
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };

            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String picturePath = cursor.getString(columnIndex);
            cursor.close();

            ImageView imageView = (ImageView) findViewById(R.id.background);
            imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));

        }
    }

Answer 1

You can't do setImageBitmap on a RelativeLayout. I think what you want to do is setBackground which takes in a Drawable as parameter.

Answer 2

That is because RelativeLayout doesn't have a method called setImageBitmap . Referring to this link , you can use this to set it to your relative layout:

File f = new File(getRealPathFromURI(path));  
Drawable d = Drawable.createFromPath(f.getAbsolutePath());
mRelativeLayout.setBackground(d);

private String getRealPathFromURI(Uri contentURI) {
        Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
        if (cursor == null) { // Source is Dropbox or other similar local file path
            return contentURI.getPath();
        } else { 
            cursor.moveToFirst(); 
            int idx = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA); 
            return cursor.getString(idx); 
        }
    }