Android NavigationView: reduce space between icon and text and `itemBackground` not working

After digging through the source. I found that you could override a dimension resource to fix this.

<dimen tools:override="true" name="design_navigation_icon_padding">16dp</dimen>

Beware though that this will change the dimension resource everywhere! You may also be able to copy the layout file and override that instead design_navigation_menu.xml

As for the different color edges, I set app:itemBackground="@android:color/transparent" and then in the theme for the NavigationView set:

<item name="selectableItemBackground">@drawable/nav_drawer_item_selector</item>

You can handle both in the theme for your NavigationView as follows:

    <item name="selectableItemBackground">@drawable/nav_drawer_item_selector</item>
    <item name="itemBackground">@color/transparent</item>

nav_drawer_item_selector.xml looks like so:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@color/white_alpha_10" />
    <item android:state_checked="true" android:drawable="@color/white_alpha_10" />
    <item android:state_focused="true" android:drawable="@color/white_alpha_10" />
    <item android:state_activated="true" android:drawable="@color/white_alpha_10" />
    <item android:drawable="@color/transparent" />
</selector>

Just add this line in dimens.xml file

<dimen tools:override="true" name="design_navigation_icon_padding">10dp</dimen>

this will override padding of NavigationView

Use app:itemIconPadding in new material NavigationView

<com.google.android.material.navigation.NavigationView
                        ...
                        app:itemIconPadding="10dp"/>