Dialogs with Expandable Areas
BCGControlBar Pro (MFC)
BCGControlBar for .NET
The expandable area contains some additional controls that initially hidden and appear only when user clicks "Expand" button located in the dialog bottom. The framework resizes dialog window according to the expandable area height.
To add this feature, simply create a new check box specifying start of the expandable area (this check box will be automatically converted to "Expand/Collapse" button) and call 'CBCGPDialog::EnableExpand' method.
Important: you cannot use this feature along with resizable dialogs or property sheets.
dlg.EnableExpand(IDC_SHOW_MORE, _T("&Show more info"), _T("&Hide details"));