Android Question Top Bar in Activity

[ciginfo]

Hello,
How to reduce the thickness of the bar that supports the title of an activity. In the example attached it is very thick, unlike what I see in all existing applications.
It is also possible to modify the color of this bar.
Thank you for your help.

 

[Erel]

This is how the default action bar in the material theme looks.

You can change it with: https://www.b4x.com/android/forum/threads/change-the-action-bar-height.122448/