The widget package contains (mostly visual) UI elements to use
on your Application screen. You can design your own
To create your own widget, extend {@link android.view.View} or a subclass. To
use your widget in layout XML, there are two additional files for you to
create. Here is a list of files you'll need to create to implement a custom
widget:
- Java implementation file - This is the file that implements the
behavior of the widget. If you can instantiate the object from layout XML,
you will also have to code a constructor that retrieves all the attribute
values from the layout XML file.
- XML definition file - An XML file in res/values/ that defines
the XML element used to instantiate your widget, and the attributes that it
supports. Other applications will use this element and attributes in their in
another in their layout XML.
- Layout XML [optional]- An optional XML file inside
res/layout/ that describes the layout of your widget. You could also do
this in code in your Java file.
ApiDemos sample application has an example of creating a custom layout XML
tag, LabelView. See the following files that demonstrate implementing and using
a custom widget:
- LabelView.java - The implentation file
- res/values/attrs.xml - Definition file
- res/layout/custom_view_1.xml - Layout
file