5.9. Button

The Button is the primary user interface component that is normally used for finalizing input and initiating some action. When the user clicks a button, a Button.ClickEvent is emitted. A listener that inherits the Button.ClickListener interface can handle clicks with the buttonClick() method.

public class TheButton extends CustomComponent implements Button.ClickListener {
    Button thebutton;

    public TheButton() {
        /* Create a Button with the given caption. */
        thebutton = new Button ("Do not push this button");
        
        /* Listen for ClickEvents. */
        thebutton.addListener(this);

        setCompositionRoot(thebutton);
    }
    
    /** Handle button click events from the button. */
    public void buttonClick (Button.ClickEvent event) {
        thebutton.setCaption ("Do not push this button again");
    }
}

Figure 5.10. An Example of a Button

As a user interface often has several buttons, you can differentiate between them either by comparing the Button object reference returned by the getButton() method of Button.ClickEvent to a kept reference or by using a separate listener method for each button. The listening object and method can be given to the constructor. For a detailed description of these patterns together with some examples, please see Section 3.5, “Events and Listeners”.

.i-button { }