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346 CHAPTER 9: Android Graphic Design: Making Your UI Designs Visual

2. Right-click on this new /res/drawable folder and select the New ➤ Android
   XML File menu sequence to get the dialog shown on the right-hand side of
   Figure 9-31. Name the file ibstates1, which stands for image button states,
   select the root element parent tag type, and then click the Finish
   button. This will open up an empty XML state definition file
   in Eclipse. A XML state definition will allow you to implement a
   selection set, much like the Java switch-case statement that you learned
   about earlier in the book. This selector will allow the Android OS to select
   amongst several different ImageButton drawable assets, based on the set of
   four android:state parameters that will define your basic ImageButton states.
   The child tags inside of the parent tag will implement
   these android:state parameters, as well as reference the image assets using
   the android:drawable parameter. This is shown in the ibstates.xml tab in
   Eclipse in Figure 9-32, and uses the following XML mark-up format:
   <?xml version="1.0" encoding="utf-8"
   
   
   
   
   
   

Figure 9-31. Right-click the /res folder and create a new folder (left) named drawable; create a new XML file (right)