adding a click effect to my button in android

Question

i have made a custom button for my layout but the problem is it doesnt show me a onclick effect. here are my three xml files that ive build i have given button an oval shape can you also tell me how to make the button a circle and smaller in size?? thnx in advance

<TextView
    android:id="@+id/textView1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="0"
    android:gravity="center"
    android:textSize="25sp" />

<Spinner 
    android:id="@+id/spin"
  android:gravity="center"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:spinnerMode="dropdown"
    android:text="heyyy"
    android:layout_below="@+id/textView1"
    />

<Button
    android:layout_marginTop="20dp"
    android:id="@+id/button1"
    android:layout_width="match_parent"
    android:layout_height="150sp"
    android:text="add"
    android:gravity="center" 
    android:layout_centerHorizontal="true"
     android:layout_below="@+id/spin"
     android:background="@drawable/button_xml"
     />
 <TextView
    android:id="@+id/textView2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
  android:layout_alignLeft="@+id/textView3"
  android:layout_below="@+id/button1"
    android:gravity="left"
    android:textSize="25sp"
    android:text="add" />

  <TextView
    android:id="@+id/textView3"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
  android:layout_below="@+id/button1"
    android:gravity="right"
    android:textSize="25sp"
     android:text="a" />
   <Button
    android:layout_marginTop="20dp"
    android:id="@+id/button2"
    android:layout_width="match_parent"
    android:layout_height="50sp"
    android:text="reset"
    android:gravity="center" 
    android:layout_centerHorizontal="true"
     android:layout_below="@+id/textView3"/>

</RelativeLayout>
</ScrollView>

button_xml.xml

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

>
<solid 
android:color="#03A89E"/>
<stroke android:width="2dp" 
        android:color="#ffffff"/>

</shape>

button_click.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="@drawable/button_xml"
    />
</selector>

Solution

here is the full XML code for button selector

button_normal.xml

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

       <solid android:color="@color/button_light_green"/>
        <corners android:radius="5dp" />

</shape>

button_selected.xml

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

       <solid android:color="@color/button_light_green_selected"/>
        <corners android:radius="5dp" />

</shape>

button_bg.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="@drawable/button_selected"/>
    <item android:state_focused="true" android:drawable="@drawable/button_selected"/>
    <item android:drawable="@drawable/button_normal"/> 
</selector>

And Finally Add it into Your button background...

<Button
android:layout_marginTop="20dp"
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="150sp"
android:text="add"
android:gravity="center" 
android:layout_centerHorizontal="true"
android:layout_below="@+id/spin"
android:background="@drawable/button_bg"/> <!-- Add Selector File here to have click effect -->