Programming Flex 3

Pop-Up Controls

Apart from the ability to programmatically create menus and menu bar navigator (discussed in the next section), there are two Flex framework controls that you can use to create pop-up controls: PopUpButton and PopUpMenuButton. Both of these controls allow a user to display a pop up. PopUpMenuButton allows the user to pop up a menu, whereas PopUpButton is more generic, allowing a user to pop up any control.

Using PopUpButton

The PopUpButton control allows you to associate the button with a pop up. The pop up can be any other UI component. Typically, you would use a pop-up button to display a small window or something similar. As you can see in Figure 7-9, the pop up appears adjacent to the button, appearing and disappearing from the button.

Figure 7-9. Using a PopUpButton to display a pop up

For the example shown in Figure 7-9, we created a simple MXML component that looks like the following:

<?xml version="1.0" encoding="utf-8"?>
<mx:TitleWindow xmlns:mx="http://www.adobe.com/2006/mxml" width="400" height="300">
    <mx:VBox>
         <mx:Label text="Select a color:" />
         <mx:RadioButton groupName="colors" label="grey" />
         <mx:RadioButton groupName="colors" label="brown" />
         <mx:Button label="Select As Color" />
    </mx:VBox>
</mx:TitleWindow>

Assuming we name the component PollWindow (and save it in the root directory), the code that allows the user to display the window using a pop-up button ...