Gets or sets the path to a Boolean value on the source task item to serve as the expansion indicator in the hierarchical collection, or null to indicate that the expansion indicator is not provided by the source task item. If a parent task is expanded its child tasks become visible. If a task node is collapsed its child tasks become invisible. This is a dependency property.

[BindableAttribute(true)]
public string IsExpandedMemberPath { get; set; }

<BindableAttribute(True)> _
Public Property IsExpandedMemberPath As String