icons_learn_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:width="35dp"
        android:height="35dp"
        android:top="2dp">
        <selector>
            <item
                android:drawable="@mipmap/icon_learn"
                android:state_checked="false"></item>
            <item
                android:drawable="@mipmap/icon_learn_pressed"
                android:state_checked="true"></item>
        </selector>
    </item>
</layer-list>