Visual Studio style Tabbed Control Bar
BCGControlBar Pro (MFC)
BCGControlBar for .NET
The library allows to create tabbed dockable windows that can be floated, docked or resized. You can detach any of the tabs to create new windows with the same ability to float, dock or make new tabbed groups.
The tab order within the tabbed control bar can be changed by dragging a tab by mouse. It's possible to disable the ability to detach individual or all tabs. You can hide or show individual tabs at runtime.
1-st step: user click on "Class View" tab:
2-nd step: drag a frame over "Toolbox" control bar. The tab indicator is appear at bottom:
"Class View" bar is groupped with "Toolbox" tab: