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all event handlers are abstract classes, so you must implement the abstract functions. For example, the onClick method is abstract, so you need to implement it in your ClickHandler class, as well as define what the onClick method is going to do.

Mixing HTML and Widgets So how can we mix widgets and html properly? Before GWT version 2.0, the most common way was to use “RootPanel.get(’someId’)” to access an HTML element in the application host page, and then create an object there to attach the widgets to (ie. a “RootPanel”). If we need to embed only a few widgets in the host page, this technique suffices. But doing this in a real application with a large number of widgets becomes complex and slow. UiBinder scales better because it does not inject widgets into the HTML of the host page. Instead, you declare your layout in a stand-alone HTML file that can be composed with other components as many times as necessary to build more complex interfaces. Composition entails componentization, allowing the developer to create subparts of the user interface (UI components) that can be packaged, re-used and tested in isolation.

11public class MyHTMLBinder extends UIObject {12 13    interface MyHTMLBinderUiBinder extends UiBinder<Element, MyHTMLBinder> {}14    private static MyHTMLBinderUiBinder uiBinder = GWT.create(MyHTMLBinderUiBinder.class);15 16    @UiField SpanElement nameSpan;17    @UiField SpanElement greetingSpan;18    @UiField DivElement divElement;19 20    public MyHTMLBinder(String firstName) {21        setElement(uiBinder.createAndBindUi(this));22 23        greetingSpan.setInnerText("Hello there ");24        nameSpan.setInnerText(firstName);25        divElement.setInnerHTML("<p> Hope you had a good time </p>");26 27    }28 29}

Gwittir is a library for GWT that provides a lot of interesting features including data binding, animation, reflection, and more. To help me learn more about this library, I decided to take it a spin and create a small GWT application to experiment with Gwittir’s data binding capabilities.

It allows you to glue together your user-interface widgets with the properties on your domain model. Whenever a user does something to a bound widget, its associated property in the model will be updated automatically. The binding is bi-directional as well,

projects which are configured manually