We have a huge activex control embedded in a Form window. When the Form
has its MDIParent set to a mdi container, the window handle of the Form
is replaced by a new one, and our control has to be InPlaceActivate
twice plus one InPlaceDeactivate( The window handles of the standard
controls within are also replaced ), This causes side effects to our
activex control. The activation involves lengthy initializations such
as downloading data from internet and heavy rendering work, so it is
too expensive to do InPlaceActivate frequently. And our control has
some operations depending on the parent window. Is there any workaround
to avoid frequent inplace activation and window re-building, for
example, creating the mdi child form directly from the MDI container?