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