Extending component with code behind

Question

Hi,
I have read an article about extending components with code
behind:
http://www.adobe.com/devnet/flex/quickstart/building_components_using_code_behind/
I have a question about that. Maybe someone can help me.
Example:
{components/CartClass.as}
package components
public class CartClass extends DataGrid
public function CartClass()
super();
{components/Cart.mxml}
<?xml version="1.0" encoding="utf-8"?>
<shop:CartClass xmlns:mx="
http://www.adobe.com/2006/mxml"
xmlns:shop="components.*"
>
</shop:CartClass>
Everthing works fine but when i add:
<mx:columns>
<mx:DataGridColumn headerText="Title" />
</mx:columns>
between the shop:CartClass tag, Flex says:
Could not resolve <mx:columns> to a component
implementation
Anyone knows why?

Answer 1

"sjerry-" <[email protected]> wrote in
message
news:gcq38m$1rg$[email protected]..
> Hi,
>
> I have read an article about extending components with
code behind:
>
http://www.adobe.com/devnet/flex/quickstart/building_components_using_code_behin
> d/
>
> I have a question about that. Maybe someone can help me.
>
> Example:
> {components/CartClass.as}
> package components
> {
> public class CartClass extends DataGrid
> {
> public function CartClass()
> {
> super();
>
> }
> }
> }
>
>
> {components/Cart.mxml}
> <?xml version="1.0" encoding="utf-8"?>
> <shop:CartClass xmlns:mx="
http://www.adobe.com/2006/mxml"
> xmlns:shop="components.*"
> >
>
> </shop:CartClass>
>
> Everthing works fine but when i add:
> <mx:columns>
> <mx:DataGridColumn headerText="Title" />
> </mx:columns>
>
> between the shop:CartClass tag, Flex says:
> Could not resolve <mx:columns> to a component
implementation
columns is actually a property of the DataGrid instance,
rather than the
DataGrid class itself, so it needs to be in the same
namespace as the actual
DataGrid subclass:
<shop:columns>
<mx:DataGridColumn headerText="Title" />
</shop:columns>