title: How can I create a crop box for camera app on an Android device?
body: <p>iI want to create a app to crop a part of picture exactly after taking a picture in camera app, like this image:</p>
  
  <p><a href="https://i.stack.imgur.com/dGRZR.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dGRZR.png" alt="Preview of photo cropping app"></a> </p>
  
  <p>But I don't know how.</p>