Android/BasicVideoCall/app/src/main/res/drawable/btn_tb_rect.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:drawable="@mipmap/btn_tb_rect_pressed" />
    <item android:drawable="@mipmap/btn_tb_rect_normal" />
</selector>