So let’s build the library by ourself:

1. Download the source archive (Note: the project moved from Google Code to github).
2. Unpack it to a folder.
3. In Flash Builder 4 select “File” > “New” > “Flex Library-Project”
4. Enter a name (e.g. “as3corelib”)
5. Select the directory of the unpacked projects
6. Select in the section “Flex SDK-Version” Flex 4.1 (or higher), if this is not your standard SDK.
7. And this is important: Select “Include AIR-Runtime-Libraries” – otherwise you’ll get include errors
8. Click on the “Done” button
9. Now you’ve got a brand new Flex library project
10. Launch the “application” by “Run” > “Run main”
11. This should result to a fresh compiled “as3corelib.swc” in your bin path of the unpacked as3corelib source archive

But fortunately it’s very easy to extend Flex components. For a project I was working I pragmatically turned off the visibility of the input field by making the TextInput field child object accessible to the outer world by adding a getter and a setter method for the ComboBase textField class property. This gives us full control over the input field. Instead of just turning visibility off you can of change other properties as the width or height.

The actionscript extension class (DateChooserPopup.as)

package customComponents

{

import mx.controls.DateField;

import mx.controls.TextInput;

public class DateChooserPopup extends DateField

{

public function DateChooserPopup()

{

super();

}

public function set TextInputField( textInput:TextInput ):void {

this.textInput = textInput;

}

public function get TextInputField():TextInput {

return this.textInput;

}

}

}

Now we use the new component within the MXML main file:

<?xml version=”1.0″ encoding=”utf-8″?>

<mx:Application xmlns:mx=”http://www.adobe.com/2006/mxml” width=”640” height=”445” layout=”absolute” backgroundGradientColors=”[#FFFFFF, #FFFFFF]” xmlns:CUSTComp=”customComponents.*“>