Create Selector for Enable/Disable Menu Item.
selector.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="@color/white" android:state_enabled="true" />
<item android:color="@color/colorPrimaryDark" android:state_enabled="false" />
</selector>
design.xml
<android.support.design.widget.BottomNavigationView
android:id="@+id/bottom_navigation"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
app:itemBackground="@color/colorPrimary"
app:itemIconTint="@drawable/nav_item_color_state"
app:itemTextColor="@drawable/nav_item_color_state"
app:menu="@menu/bottom_navigation_main" />