sliding_pane.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.slidingpanelayout.widget.SlidingPaneLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/sliding_pane_layout">

    <androidx.fragment.app.FragmentContainerView
        android:id="@+id/primary_nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="@dimen/list_width"
        android:layout_height="match_parent"
        android:layout_gravity="start"/>

    <androidx.fragment.app.FragmentContainerView
        android:id="@+id/detail_nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="@dimen/item_width"
        android:layout_height="match_parent"
        android:layout_weight="1" />

</androidx.slidingpanelayout.widget.SlidingPaneLayout>