Now on Android Studio 2.2 on new Preview mode, there are no more refresh button:
Does anyone know how to display it again? Or with shortcut maybe?
Edit: If I change a drawable by example and that the change does not appear in the layout, the only method that works for me is closed and restart the project. If I close the layout and as I re-opens nothing happens. Same result using the "Synchronized" button.
Refresh feature is not removed, it is there; It's pretty simple to refresh:
Click on the preview screen to make sure preview window has the focus and press R. It should display the progress in the right-top corner while refreshing.
If it doesn't work for any reason, switch to design tab and press R, it refreshes the layout instantly.