app/src/main/res/menu/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_videos"
android:icon="@drawable/ic_video_library_black_24dp"
android:title="@string/nav_local_videos" />
<item
android:id="@+id/nav_zbigz"
android:icon="@drawable/ic_zbigz_black_24dp"
android:title="@string/nav_zbigz" />
<item
android:id="@+id/nav_live_tv"
android:icon="@drawable/ic_live_tv_black_24dp"
android:title="@string/nav_live_tv" />
</group>
<item android:title="@string/nav_contact">
<menu>
<item
android:id="@+id/nav_share"
android:icon="@drawable/ic_share_black_24dp"
android:title="@string/nav_share" />
<item
android:id="@+id/nav_website"
android:icon="@drawable/ic_web_black_24dp"
android:title="@string/nav_visit_website" />
</menu>
</item>
</menu>