Android: Bottom Navigation View - change icon of selected item

I found this is better approach to use selector drawable:

At first create an xml file in your drawable folder. For example, xml file name is child_selector.xml at drawable folder.

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/child" android:state_checked="false"/>
    <item android:drawable="@drawable/child_fill" android:state_checked="true"/>
</selector>

Simply add child_selector in menu item of your bottom_navigation_main.xml:

Like: android:icon="@drawable/child_selector"

Example:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

<item
    android:id="@+id/navigation_child"
    android:icon="@drawable/child_selector"
    android:title="@string/title_child" />

</menu>

And must add following line in your activity-

bottomNavigationView.setItemIconTintList(null);

Good luck.

You can simply create drawable selector in drawable folder and image can be change according to the state of the widget used in view

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/calender_green" android:state_checked="true"/>
    <item android:drawable="@drawable/calender_black" android:state_checked="false"/>
</selector>