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Hi,
it seems to me, that OnPaint is not called when inherited from CExtResizableDialog. If I use CDialog instead, all works fine.
What I have done wrong??

TIA Willi

I have to ’paint’ on CExtResizablePropertyPage. Implementing the same WM_PAINT technique there does not work. WM_PAINT did not happened. We have in the code:

IMPLEMENT_DYNCREATE(CKWP_Computer, CExtResizablePropertyPage)

CKWP_Computer::CKWP_Computer() : CExtResizablePropertyPage(CKWP_Computer::IDD)
{
}

and

class CKWP_Computer : public CExtResizablePropertyPage
{
    DECLARE_DYNCREATE(CKWP_Computer)
protected:
virtual LRESULT WindowProc( UINT message, WPARAM wParam, LPARAM lParam )
{
if( message == WM_PAINT )
{
AfxMessageBox("painting");
CPaintDC dc( this );

...

We guess the page window contains some control(s) which cover the client area of the page completely.

If you take a look at the declaration of CExtResizableDialog, you will see that its parent classes are wrapped in templates. The template classes cannot have message handlers like OnPaint() for implementing window behavior and appearance. So we had to implement the WindowProc() virtual method in them. The CExtWS template class adds a theme-based background to the resizable dialog window and eats up the WM_PAINT standard windows message in its WindowProc() method. That is why the OnPaint() method is not invoked in dialog classes derived from the CExtResizableDialog class. You can also override the WindowProc() method and handle the WM_PAINT standard windows message there:

class C_Your_Dialog : public CExtResizableDialog
{
protected:
    virtual LRESULT WindowProc( UINT message, WPARAM wParam, LPARAM lParam )
    {
        if( message == WM_PAINT )
        {
            CPaintDC dc( this );
            // 
            // YOUR CUSTOM PAINTING CODE GOES HERE 
            //
            return 0;
        }
        return CExtResizableDialog::WindowProc( message, wParam, lParam );
    }
};

Thanks for your help, works fine!!
Willi