public PanelViewModelBase Open(PanelViewModelBase vm) { var panelViewModelBase = _panels.FirstOrDefault(p => p == vm); if (panelViewModelBase == null) { panelViewModelBase = vm; _panels.Add(panelViewModelBase); } ActiveDocument = panelViewModelBase; return(panelViewModelBase); }
internal void Close(PanelViewModelBase panel) { _panels.Remove(panel); }