I'm developing an ATL composite control which has two components (a button and a list box). The list box won't be visible initially; when the button is clicked the list box should appear. The initial area of the composite control just accomodates the button. Only when the button is clicked the composite control area should be increased to accomodate the list box. I tried changing the values of m_sizeExtent and m_sizeNormal; it didn't work. Is there a way to solve this issue? Your suggestions will be valuable.