android studio 3.3 not showing action bar and status bar in its preview window after creating new project.i already tried this in build.graadle(module:app) file (implementation'com.android.support:appcompat-v7:28.0.0-alpha1')
In the preview tab, click on the eye and select 'Show Layout Decorations'.
EDIT: Toolbar isn't showing because of my style settings - I used 'NoActionBar'. This should work for you, though.