title: set custom ringtone to specific contact number in Android 7
body: <blockquote>
    <p>how can I set a ringtone for a specific contact?</p>
  </blockquote>
  
  <pre><code>int result =  getContentResolver().update(contactUri, ContentValues, null, null);
  </code></pre>
  
  <blockquote>
    <p>result = 1
    but custom ringtone is not updating in android 7 or above</p>
  </blockquote>