MACROMEDIA COLDFUSION MX 7.0.2-USING COLDFUSION MX WITH FLEX 2 Guide de l'utilisateur télécharger pdf (Page 143)

143

CHAPTER 12

Use an Event Listener

When you develop Adobe Flex applications, event handling is one of the most basic and

important tasks. Events let you know when something happens within a Flex application.

They can be generated by user devices such as the mouse and keyboard, or other external

input such as the return of a web service call. Events are also triggered when changes happen

in the appearance or life cycle of a component, such as the creation or destruction of a

component or when the component is resized.

You can respond to these events in your code by using event listeners. Event listeners are

functions or class methods that you write to respond to specific events. They’re also known as

event handlers.

This lesson shows you how to use an event listener. You’ll learn how to write one for a Button

control, and then how to associate the listener with the Button’s click event by using two

different methods.

In this lesson, you’ll complete the following tasks:

Set up your project. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Create a simple user interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144

Write an event listener. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

Associate the listener with an event with MXML. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Associate the listener with an event with ActionScript . . . . . . . . . . . . . . . . . . . . . . . 148

1 2 ... 138 139 140 141 142 143 144 145 146 147 148 ... 255 256

Pas de commentaire

MACROMEDIA COLDFUSION MX 7.0.2-USING COLDFUSION MX WITH FLEX 2 Guide de l'utilisateur Page 143