Single link from a node port

GoXam
1

Hello everyone,

I have a diagram and I want a node to have ONLY ONE link that comes out from a node port.
I’m using a GraphLinksModel.

Should I create a custom (Re)LinkingTool that check in the LinksSource if there is already a link that start from the node?
Is there a better way to do that?
Is there an example that implement that feature?

Thank you very much

Andrew

2

If you don’t have to worry about any links going into that port, you can just set go:Node.LinkableMaximum=“1” on that port element.

If you may have a variable number of links going into that port, you can override [Re]LinkingTool.IsValidLink to check for the cases you want to allow. There are some examples of this in the demo app.

3

I’m having some troubles implementing it.

I have these two ports in my Node DataTemplate:


How can I get the link PortIds from inside the function IsValidLink in LinkingTool? (I should read “In” or “Out” somewhere).

4

If you want to limit the number of links that can be drawn coming out of your “Out” port, you just need to set go:Node.LinkableMaximum=“1”. That is possible because you are not allowing any links to go into that “Out” port.

5

Thank you walter, I’ll try that way.

But can you tell me how can I get the portId on the from/to node when I’m inside the function IsValidLink in LinkingTool?


Thanks again

6

Just get the go:Node.PortId attached property from the FrameworkElement that is the port, for example:
Node.GetPortId(fromport)

7

Right.

Thank you very much!