In this case you can add to FlyGrid unvisible(hidden) column (last column fro example), init node as following:
Dim data As Object() = New Object() {attName, attDesc, attVisible, attPipeVisible, attIsoVisible, attMode, attReadOnly }
and analyze this data in the IsReadOnly event:
bool isReadOnly = (bool)node("ReadOnly")
return isReadOnly
or you can create your own type of Node with ReadOnly property that will initialized in your procedure:
Dim data As Object() = New Object() {attName, attDesc, attVisible, attPipeVisible, attIsoVisible, attMode}
Dim newNode as NodeWithReadOnly = New NodeWithReadOnly(data)
newNode.ReadOnly = attReadOnly
Me.FlyGrid1.Rows.Items.Add(newNode)
In this case your code in the IsReadOnly will:
Dim nodeRO as NodeWithReadOnly = CType(node, NodeWithReadOnly)
return nodeRO.ReadOnly