Creating custom flex components using Actionscript

You already know how easy it is to create your own custom component by extending the functionality of other components (both built-in and custom) using MXML alone. You will now see how to do it, using ActionScript.

Lets name our component, BooleanComboBox. You create this custom component, by extending the ComboBox, which is a built-in component. Your component class must be created inside a package for it to be referenced later on. The code is shown below :

package components
{
import mx.controls.ComboBox;
public class BooleanComboBox extends ComboBox
{
    public function CountryComboBox()
    {
        dataProvider = [ "True", "False" ];
    }
}
} 

As you can see, in the constructor of this class, we are loading the values "True" and "False" into the dataprovider. As simple as that !

For you to use it in your MXML, there is nothing new to be done. Use it the way you had when you created the component using MXML alone.

<?xml version="1.0"?>
<mx:application mx="http://www.adobe.com/2006/mxml" cc="components.*">
<!-- Use the filename as the MXML tag name. -->
<cc:BooleanComboBox/>
</mx:Application>

So, you now know how you can create your own custom components. Couldn't get simpler than that.
Will talk about communicating with a server in the next post.