Android:如何使用Async下载.png文件并将其设置为ImageView？

private class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
    private ImageView imageView;

    public DownloadImageTask(ImageView imageView) {
        this.imageView = imageView;
    }

    protected Bitmap doInBackground(String... urls) {
        String url = urls[0];
        Bitmap bitmap = null;
        try {
            InputStream inputStream = new URL(url).openStream();
            bitmap = BitmapFactory.decodeStream(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return bitmap;
    }

    protected void onPostExecute(Bitmap bitmap) {
        imageView.setImageBitmap(bitmap);
    }
}

String imageUrl = "https://example.com/image.png";
ImageView imageView = findViewById(R.id.image_view);
new DownloadImageTask(imageView).execute(imageUrl);