Base class for custom components - apache-flex

Question

In my flex app I have various custom components done with mxml or actionscript.
I want all of them to extend a base-class where I can define properties/event listeners etc.
Can someone give me an example how to create that base class and how I can extend it in mxml and actionscript components?

Answer 1

Maybe you could write a common interface for your components, just with the methods they need to implement
public interface ICustomComponent {
function doSomething():void;
// more methods here
}
And then in your AS components you just implement the ICustomComponent interface (or however you named it)
public class CustomButton extends Button implements ICustomComponent {
public function doSomething():void {
}
}
You can do this in MXML components too :
<mx:Button xmlns:mx="http://www.adobe.com/2006/mxml"
implements="ICustomComponent">
<mx:Script>
<![CDATA[
public function doSomething():void {
// blah blah
}
]]>
</mx:Script>
</mx:Button>
Just an idea. Hope it helps
Cheers

Answer 2

Creating the base class:
ActionScript
In BaseClass.as:
public class BaseClass
{
}
Extending from the base class:
ActionScript
public class SubClass extends BaseClass
{
}
MXML
In a file called SubClass.mxml:
<ns:BaseClass xmlns:ns="path.to.base.*">
</ns:BaseClass>

Answer 3

In the example below the component extends Form to create an address form .
Instead of form you can extend your own component .
When using actionscript i would suggest investigating flex components lifecycle for best performance :
http://livedocs.adobe.com/flex/3/html/help.html?content=ascomponents_advanced_2.html
mx:Form xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:MyComp="*"
<mx:FormItem label="NameField">
<mx:TextInput/>
</mx:FormItem>
<mx:FormItem label="Street">
<mx:TextInput/>
</mx:FormItem>
<mx:FormItem label="City" >
<mx:TextInput/>
</mx:FormItem>
<mx:FormItem label="State" >
<MyComp:StateComboBox/>
</mx:FormItem>
The following application file references the AddressForm component in the
AddressForm tag:
mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
xmlns:MyComp="*"
<MyComp:AddressForm/>
/mx:Application
from http://livedocs.adobe.com/flex/3/html/help.html?content=mxmlcomponents_1.html