activityxml_just toolbar and tabs_Mark3

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">
    <com.google.android.material.appbar.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        >
        <androidx.appcompat.widget.Toolbar
            android:id="@+id/myToolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="@color/colorPrimary"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            />
        <com.google.android.material.tabs.TabLayout
            android:id="@+id/myTab"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:tabIndicatorColor="@android:color/white"
            app:tabIndicatorHeight="2dp"
            app:tabMode="fixed"
            app:tabGravity="fill"
            />
    </com.google.android.material.appbar.AppBarLayout>
    <androidx.viewpager.widget.ViewPager
        android:id="@+id/myViewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior"
        />
</androidx.coordinatorlayout.widget.CoordinatorLayout>