android button selector

You just need to set selector of button in your layout file.

<Button
     android:id="@+id/button1"
     android:background="@drawable/selector_xml_name"
     android:layout_width="200dp"
     android:layout_height="126dp"
     android:text="Hello" />

and done.

Edit

Following is button_effect.xml file in drawable directory

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

    <item android:drawable="@drawable/numpad_button_bg_selected" android:state_selected="true"></item>
    <item android:drawable="@drawable/numpad_button_bg_pressed" android:state_pressed="true"></item>
    <item android:drawable="@drawable/numpad_button_bg_normal"></item>

</selector>

In this, you can see that there are 3 drawables, you just need to place this button_effect style to your button, as i wrote above. You just need to replace selector_xml_name with button_effect.