res/drawable/custom_button.xml

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

    <item android:state_pressed="true" >
        <shape>
            <gradient
                android:startColor="#ffffff"
                android:endColor="#dddddd"
                android:angle="270" />
            <stroke
                android:width="3dp"
                color="#0000ff" />
            <corners
                android:radius="20dp" />
            <padding
                android:left="10dp"
                android:top="10dp"
                android:right="10dp"
                android:bottom="10dp" />
        </shape>
    </item>

    <item>        
        <shape>
            <gradient
                android:endColor="#dddddd"
                android:startColor="#bbbbbb"
                android:angle="270" />
            <stroke
                android:width="3dp"
                color="#ff00ff" />
            <corners
                android:radius="20dp" />
            <padding
                android:left="10dp"
                android:top="10dp"
                android:right="10dp"
                android:bottom="10dp" />
        </shape>
    </item>
</selector>
1	<?xml version="1.0" encoding="utf-8"?>
2	<selector
3	xmlns:android="http://schemas.android.com/apk/res/android">
4
5	<item android:state_pressed="true" >
6	<shape>
7	<gradient
8	android:startColor="#ffffff"
9	android:endColor="#dddddd"
10	android:angle="270" />
11	<stroke
12	android:width="3dp"
13	color="#0000ff" />
14	<corners
15	android:radius="20dp" />
16	<padding
17	android:left="10dp"
18	android:top="10dp"
19	android:right="10dp"
20	android:bottom="10dp" />
21	</shape>
22	</item>
23
24	<item>
25	<shape>
26	<gradient
27	android:endColor="#dddddd"
28	android:startColor="#bbbbbb"
29	android:angle="270" />
30	<stroke
31	android:width="3dp"
32	color="#ff00ff" />
33	<corners
34	android:radius="20dp" />
35	<padding
36	android:left="10dp"
37	android:top="10dp"
38	android:right="10dp"
39	android:bottom="10dp" />
40	</shape>
41	</item>
42	</selector>