How to remove padding from line shown in NavigationView app menu group item

Question

I've started the default Android project, "Navigation Drawer Activity".

I've changed the theme to:

<!-- <style name="Theme.MyApplication" parent="Theme.MaterialComponents.DayNight.DarkActionBar">-->
    <style name="Theme.MyApplication" parent="Theme.Material3.DayNight.NoActionBar">

I've added a group item:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:showIn="navigation_view">

    <group android:checkableBehavior="single">
        <item
            android:id="@+id/nav_home"
            android:icon="@drawable/ic_menu_camera"
            android:title="@string/menu_home" />
        <item
            android:id="@+id/nav_gallery"
            android:icon="@drawable/ic_menu_gallery"
            android:title="@string/menu_gallery" />
        <item
            android:id="@+id/nav_slideshow"
            android:icon="@drawable/ic_menu_slideshow"
            android:title="@string/menu_slideshow" />
    </group>
    <!--    added this:-->
    <group
        android:id="@+id/nav_other"
        android:checkableBehavior="single">
        <item
            android:id="@+id/nav_cancel_payment"
            android:icon="@drawable/ic_menu_slideshow"
            android:title="Test Title"
            android:enabled="true"/>
    </group>
</menu>

The horizontal line has padding left and right. I want 0 padding. How can I achieve this?

Answer 1

The padding of the divider (with M3) is defined by the attributes dividerInsetStart and dividerInsetEnd (default value with M3 = 28dp).

You can override them using in your layout:

<com.google.android.material.navigation.NavigationView
    android:id="@+id/nav_view"
    app:dividerInsetStart="0dp"
    app:dividerInsetEnd="0dp"

or with a custom style:

<com.google.android.material.navigation.NavigationView
    android:id="@+id/nav_view"
    style="@style/App.Material3.NavigationView"

where:

<style name="App.Material3.NavigationView" parent="Widget.Material3.NavigationView">
    <item name="dividerInsetStart">0dp</item>
    <item name="dividerInsetEnd">0dp</item>
</style>