CXTPControlPopup issue

Hi ;

i want to create a popup bar programatically.
i did it like this :
CXTPPopupToolBar* pFlyOutBar=(CXTPPopupToolBar*) CXTPPopupToolBar::CreatePopupToolBar(pCommandBars);

CXTPControlPopup* pControl = (CXTPControlPopup* )pGroup->Add(xtpControlSplitButtonPopup, cmdIDBtn);

pControl->SetCommandBar(pFlyOutBar);
pFlyOutBar->InternalRelease();

By doing this i am able to create a splitButton type PopupControl.

all things done good till now.

Now i want to update the main button Text, when user click any button in the list.(the behavious same as the flyout in the toolbar)

i want to update the properties of the main popup container .
How can i ?

i am attaching the bmp for clear visualisation of my problem .

Thnx