Android Bottom Nav Activity
问题 I am trying to use Bottom Navigation Activity. I use the default 3 menu items with their fragments. My problem is, I am seeing a gap between the ActionBar and the fragment. In the activity_main, I set the height to match_parent . I tried to see if anyone else has this problem but could not come across. In the activity_main.xml file, I have the code that comes with a creation of a new activity: <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res