Customize event handler for TextComboBoxWidget

Has anybody been able to get an event handler on TextComboBoxWidget yet?

My problem is that I have a combobox on a dialog. While it is selected and an enter key is pressed, I need to do some validation and stop the dialog from being closed if the input is invalid.

I tried to make a custom widget like

Class

    {

        kMyTextEditBoxWidgetBoss,

        kTextEditBoxWidgetBoss,

        {

            /** The plug-in's implementation of an event handler,

                extending CIDEditBoxEventHandler.

            */

            IID_IEVENTHANDLER,            kMyEditBoxEventHandlerImpl,   

        }

    },

type MyNonEveEditBoxWidget (kViewRsrcType) : TextEditBoxWidget (ClassID = kMyTextEditBoxWidgetBoss) {};

type MyEditBoxWidget (kViewRsrcType) : MyNonEveEditBoxWidget(ClassID = kMyTextEditBoxWidgetBoss)

{

    WidgetEveInfo;

};

type MyComboBoxWidget (kViewRsrcType) : MyNonEveEditBoxWidget(ClassID = kTextComboBoxWidgetBoss)

{   

    DropDownListControlData;

    WidgetEveInfo;

};

While this works for MyEditBoxWidget(as illustrated in cellpanel sdk example), it does not give me the control in case of MyComboBoxWidget.

Is there any other way if not an event handler to do it?

The issue still exists.

Still need help.