The TemplatedControlDesigner.EnterTemplateMode(ITemplateEditingFrame) method is obsolete. Use the TemplatedControlDesigner.TemplateGroups property to manipulate templates within a designer for template-based controls.
If already in template mode and editing a different template frame, this method calls TemplatedControlDesigner.ExitTemplateMode(bool, bool, bool) to save all its templates and close that frame.