linphone-android/app/src/main/res/drawable/icon_meeting_schedule.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <bitmap android:src="@drawable/voip_meeting_schedule"
            android:tint="?attr/drawableTintColor"/>
    </item>
</selector>