Many toolbar characteristics can be modified. These include toolbar visibility, position and the number of rows present in the toolbar.
A toolbar can be made visible or hidden using LToolbar::SetVisible. To determine whether the toolbar is visible or hidden, call LToolbar::IsVisible.
The position of the toolbar can be changed using LToolbar::SetPosition. This function allows the user to specify a point and orient the toolbar around that point. To get the current position, call LToolbar::GetPosition.
The number of rows in the toolbar can also be set. This is done using the LToolbar::SetRows function. However, the number of rows cannot exceed the number of buttons in the toolbar. To determine the current number of rows in the toolbar, call LToolbar::GetRows.
A toolbar can also be changed by changing the buttons contained in the toolbar.
For more information, refer to:
Direct Show .NET | C API | Filters
Media Foundation .NET | C API | Transforms