Referring to http://ko.infragistics.com/samples/wpf/diagram/binding-nodes-with-objects
Can you please suggest recommended way of aligning new nodes if a child node is created on fly. I have set TreeDiagramLayout's NodeFlowDirection to "Below" but when a new object is added in viewmodel at run time it goes to top left corner of diagram.
Ideally starting from parent, I would like nodes to be center aligned and newly created to be below parent node.
Hello Abs,
The diagram layout is applied only initially to the diagram. If the items are added/removed later (eg. view model collection), the layout is not automatically applied. In order to rearrange the nodes at a later stage, call the RefreshLayout method directly on the XamDiagram.
eg.
mainWindow.Diagram.RefreshLayout();
For more details please visit:http://ko.infragistics.com/help/wpf/xamdiagram-configuring-the-layout
If you require a custom position you can use the diagram's items collection changed event to do so:
private void Items_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) { FamilyTreeViewModel vm = this.Diagram.DataContext as FamilyTreeViewModel;
if (e.NewStartingIndex >= vm.FamilyTree.Count) { if (e.NewItems[0] is DiagramNode) {
DiagramNode newlyAdded = e.NewItems[0] as DiagramNode; newlyAdded.Position = new Point(50, 50); } } }
Let me know if you have any questions regarding this matter.
Thank you for these ideas. This link is broken for me!
http://help.infragistics.com/Help/Doc/WPF/2016.2/CLR4.0/html/xamDiagram_Configuring_the_Layout.html
Thanks for coming back to me, I had the same code and exception is raised when a node is added to the leaf node.
Is this still an issue? Please provide some code snippet in the CollectionChanged event and I will take a look.
You can use the same code you attached and select any leaf node and then add a new node, it raises an exception.
Thank you for following up. This again is related to the time it takes to load the nodes and the layout. Please wrap the RefreshLayout method inside an asyncronyons Dispatcher.BeginInvoke method:
private void Items_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) { MainWindowViewModel vm = this.EmployesDiagram.DataContext as MainWindowViewModel;
if (e.NewStartingIndex >= vm.Employees.Count) { Dispatcher.Invoke(async () => { this.EmployesDiagram.RefreshLayout(); }); } }
Let me know if you have any questions.
Ok, thank you for the suggestion.