activity_main_drawer.xml

<?xml version="1.0" encoding="utf-8"?>
<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_focus"
            android:icon="@drawable/ic_card_focus"
            android:title="@string/focus" />
        <item
            android:id="@+id/nav_relax"
            android:icon="@drawable/ic_card_relax"
            android:title="@string/relax" />
        <item
            android:id="@+id/nav_meditation"
            android:icon="@drawable/ic_card_meditation"
            android:title="@string/meditation" />
        <item
            android:id="@+id/nav_memory_graph"
            android:icon="@drawable/ic_card_mem_graph"
            android:title="@string/mem_graph" />
    </group>

    <item
        android:id="@+id/nav_data_logger"
        android:icon="@drawable/ic_import"
        android:title="@string/logged_data" />

    <item
        android:id="@+id/nav_connect_device"
        android:icon="@drawable/ic_device_connected"
        android:title="@string/connect_device" />

    <item
        android:id="@+id/nav_settings"
        android:icon="@drawable/ic_settings"
        android:title="@string/settings" />

    <item android:title="@string/other_head_nav_drawer">
        <menu>
            <item
                android:id="@+id/nav_about_us"
                android:icon="@drawable/ic_info"
                android:title="@string/about_us" />
            <item
                android:id="@+id/report_or_bug"
                android:checked="false"
                android:icon="@drawable/ic_baseline_bug_report_24"
                android:title="@string/report_or_bug"/>
            <item
                android:id="@+id/item_help"
                android:checked="false"
                android:icon="@drawable/ic_baseline_help_24"
                android:title="@string/help"/>
            <item
                android:id="@+id/nav_share"
                android:icon="@drawable/ic_menu_share"
                android:title="@string/share_nav_drawer" />
        </menu>
    </item>

</menu>