如何在android中动态下载自定义字体？

<uses-permission android:name="android.permission.INTERNET" />

private class DownloadFontTask extends AsyncTask<String, Void, Typeface> {
    protected Typeface doInBackground(String... urls) {
        String fontUrl = urls[0];
        try {
            URL url = new URL(fontUrl);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            InputStream inputStream = connection.getInputStream();
            File fontFile = new File(getFilesDir(), "custom_font.ttf");
            FileOutputStream outputStream = new FileOutputStream(fontFile);
            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = inputStream.read(buffer)) != -1) {
                outputStream.write(buffer, 0, bytesRead);
            }
            outputStream.close();
            inputStream.close();
            return Typeface.createFromFile(fontFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    protected void onPostExecute(Typeface typeface) {
        if (typeface != null) {
            // 在这里设置字体
            textView.setTypeface(typeface);
        }
    }
}

String fontUrl = "https://example.com/custom_font.ttf";
new DownloadFontTask().execute(fontUrl);