welcome_nav_graph.xml

<?xml version="1.0" encoding="utf-8"?>
<navigation 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:id="@+id/welcome_nav_graph"
    app:startDestination="@id/mainFragment">

    <fragment
        android:id="@+id/mainFragment"
        android:name="com.praszapps.mysamplenavapp.MainFragment"
        android:label="fragment_main"
        tools:layout="@layout/fragment_main" >
        <action
            android:id="@+id/action_mainFragment_to_destinationFragment"
            app:destination="@id/destinationFragment" />
    </fragment>
    <fragment
        android:id="@+id/destinationFragment"
        android:name="com.praszapps.mysamplenavapp.DestinationFragment"
        android:label="fragment_destination"
        tools:layout="@layout/fragment_destination" />
    <argument
    android:name="nameToShow"
    android:defaultValue="Andy"
    app:argType="string" />
</navigation>

Is the argument meant to go inside the deatinationFragment fragment element?