Link routes resetting

GoXam
1

Hi,

we have a problem with links routing after reloading nodes and links in the diagram.
We do not reload the whole Diagram - we just clear nodes and links in Diagrams model, and than - we add nodes and links, previously saved. Reloading takes place in a transaction. After transaction commit, link routes are resetting. I know, that there were already posted some issues to this problem. But I couldn’t get this to work.

Here is the code that reloads all nodes and links:

                _model.Model.StartTransaction("initial");
                if (_model.Nodes.Any() && _model.Links.Any())
                {
                    _model.Nodes.Clear();
                    _model.Links.Clear();
                }

                foreach (var node in nodes)
                {
                    var model = new NodeViewModel(node);
                    _model.Nodes.Add(model);
                }

                foreach (var link in links)
                {
                    var model = new LinkViewModel(link);
                    _model.Links.Add(model);
                }
                _model.Model.CommitTransaction("initial");

In LinkViewModel constructor, which inherits: GraphLinksModelLinkData<string, string>, I write it’s Points value.

A have also tried to write Link.Route values in PartManagers’ overrided OnModelChange from my LinkViewModel - but it still did not work.

2

Do you avoid the problem if you create a new model and replace Diagram.Model? Instead of modifying the existing model.

3

No. I tried this method, but It also does not help.

4

Are you doing what some of the samples do in order to load link routes? For example, the Draggable Link sample does this when loading a model:

      myDiagram.PartManager.UpdatesRouteDataPoints = false;  // tell the CustomPartManager that we're loading

        XElement root = XElement.Parse(/*Demo.MainPage.Instance.*/SavedXML);
        // set the Route.Points after nodes have been built and the layout has finished
        myDiagram.LayoutCompleted += LoadLinkRoutes;
        model.Load<MyData, MyLinkData>(root, "Node", "Link");

and:

    // no data-binding of Route.Points means we have to copy the Points data explicitly
    private void LoadLinkRoutes(Object s, EventArgs e) {
      // just set the Route points once per Load
      myDiagram.LayoutCompleted -= LoadLinkRoutes;
      foreach (Link link in myDiagram.Links) {
        var d = link.Data as MyLinkData;
        if (d == null || d.Points == null) continue;
        link.Route.Points = (IList<Point>)d.Points;
      }
      myDiagram.PartManager.UpdatesRouteDataPoints = true;  // OK for CustomPartManager to update Transition.Points automatically
    }
5

Ok, this time it is working. Thanks for help.