public SubTreeRootDependencyNode(string providerType, string caption, ProjectTreeFlags flags, ImageMoniker icon, ImageMoniker?expandedIcon = null, int priority = 0) : base(new DependencyNodeId(providerType, string.Empty, string.Empty), flags, priority, null, resolved: true) { Requires.NotNullOrEmpty(caption, nameof(caption)); Caption = caption; Icon = icon; ExpandedIcon = expandedIcon ?? Icon; Flags = flags.Add(SubTreeRootNodeFlags.ToString()); }