BottomAppBar Being Pushed Off Screen

When I switch from any fragment back to Shopping List with the bottom app bar, it gets pushed down off the screen and I don't know why. Switching between the Fridge Fragment and P

Solution 1:

Try with these changes for FrameLayout and I guess you won't need fragment_navigation.xml after that.

activity_main.xml:

<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/relative_layout_for_fragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

    <com.google.android.material.bottomappbar.BottomAppBar
        android:id="@+id/bottom_app_bar"
        style="@style/Widget.MaterialComponents.BottomAppBar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:theme="@style/ThemeOverlay.MaterialComponents.Dark.ActionBar"
        app:backgroundTint="@color/colorPrimary"
        app:hideOnScroll="true"
        app:layout_scrollFlags="scroll|enterAlways"
        app:navigationIcon="@drawable/ic_menu_white_24dp" />

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_add_shopping_cart_white_24dp"
        app:fabSize="normal"
        app:layout_anchor="@id/bottom_app_bar" />

</androidx.coordinatorlayout.widget.CoordinatorLayout>

You also said that it happens when you switch to ShoppingListFragment which has another CoordinatorLayout in there.

You simply change fragment_shopping_list.xml codes as follows:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/shopping_fragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="141dp"
        android:text="TextView" />

</RelativeLayout>

Or just don't use CoordinatorLayout in there then try.