Introduction

First, create an Android Project in the Eclipse IDE.
Android Project
Then open the XML file and drag and drop one button to the Graphical Layout of the XML file.
drag and drop one button in
Now create one XML file in the drawable folder and use two images for seeing the changes on a button press.
Create one xml file
drawable folder
Chosen qualifiers
Default Button Image.
Default Button Image
On Button Pressed Image.
Button Pressed Image
Paste both the images into the drawable folder.
design
Open the design.xml file and write the following code in the XML file,
  1. <?xml version="1.0" encoding="utf-8"?>
  2. <selector xmlns:android="http://schemas.android.com/apk/res/android">
  3. <item android:state_pressed="true"
  4. android:drawable="@drawable/buttonclicked" /> <!-- pressed -->
  5. <item android:drawable="@drawable/buttondefault" /> <!-- default -->
  6. </selector>
    Here buttonclicked and buttondefault are the image's name.
    Now open the activity_main.xml file from the layout folder and here's the file code:
    1. <RelativeLayout
    2. xmlns:android="http://schemas.android.com/apk/res/android"
    3. xmlns:tools="http://schemas.android.com/tools"
    4. android:layout_width="match_parent"
    5. android:layout_height="match_parent"
    6. android:paddingBottom="@dimen/activity_vertical_margin"
    7. android:paddingLeft="@dimen/activity_horizontal_margin"
    8. android:paddingRight="@dimen/activity_horizontal_margin"
    9. android:paddingTop="@dimen/activity_vertical_margin"
    10. tools:context="com.example.demo.MainActivity" >
    11. <Button
    12. android:id="@+id/button1"
    13. android:layout_width="wrap_content"
    14. android:layout_height="wrap_content"
    15. android:layout_alignParentLeft="true"
    16. android:layout_alignParentRight="true"
    17. android:layout_alignParentTop="true"
    18. android:layout_marginTop="97dp"
    19. android:text="Button"
    20. android:background="@drawable/design"/>
    21. </RelativeLayout>
      android: background=”@drawable/design” is used to select the design.xml file in the background of the button.
      Then run the Android application.
      Before the button is pressed
      Before Button Pressed
      On pressing the button
      Button Pressed

      Summary

      So you can use this XML file is for any object in Android and is also useful for anything in design.xml such as images and colors.
      Thank you.