Informs the taskbar that a new tab or document thumbnail has been provided for display in an application's taskbar group flyout.
HRESULT RegisterTab( HWND hwndTab, HWND hwndMDI );
Handle of the tab or document window. This value is required and cannot be NULL.
Handle of the application's main window. This value tells the taskbar which application's preview group to attach the new thumbnail to. This value is required and cannot be NULL.
Returns S_OK if successful, or an error value otherwise. If either parameter is NULL, this method returns an error.
By itself, registering a tab thumbnail alone will not result in its being displayed. You must also call ITaskbarList3::SetTabOrder to instruct the group where to display it.
|Minimum supported client||Windows 7 [desktop apps only]|
|Minimum supported server||Windows Server 2008 R2 [desktop apps only]|
|Header||shobjidl_core.h (include Shobjidl.h)|