make toolbar fill a row of dockbar

I want to implement a CXTPToolbar which can auto fill a row of dockbar , the toolbar   contain some controls which can stretch such as CXTPComBox, I realize such code:

//the above code can stretch the toolbar
void CXTPToolBar::AdjustWidth(int nAddedWidth, BOOL bFill)
{
 for(int i=0;i<GetControls()->GetCount();i++)
 {
  CXTPControl* pControl = m_pControls->GetAt(i);

  if(pControl->IsKindOf(RUNTIME_CLASS(CXTPContr olComboBox))
   &&(pControl->GetFlags()&xtp FlagControlStretched)) 
  {
   CXTPControlComboBox* pCombox = (CXTPControlComboBox*) pControl;
   if(bFill)
    nAddedWidth = GetDockBar()->GetMaxFreeWidth(this);   

   pCombox->SetWidth(pCombox->GetWidth( )+nAddedWidth);
   pCombox->SetDropDownWidth(pCombox->G etWidth()+nAddedWidth);
  }
 }
}

but my problem lies in: when I make a toolbar fill a row of dockbar, the drag action
will change ,for example, if I drag a toolbar to the stretched toolbar, the drag can't
happen, to avoid this, the stretched toolbar should auto decrease its width to meet the
drag requirement. How can do? 

no one can help me?

How is xtpFlagControlStretched used? I have a combo on a command bar that I want to size automatically to the size of the command bar rather than being fixed in size. I tried this in the WordPad sample in CMainFrame::CreateToolBars()

pFormatBar->GetControls()->FindControl(ID_COMBO_FONT)- >SetFlags(xtpFlagControlStretched);

but it had no apparent effect. I can't find any samples using it either, and the docs just say "Indicates the control is stretched in the parent command bar".

I have the same problem.anybody resolved?