Binding more than one value

GoJS
1

Dear Northwoods Software,
we are evaluating GoJS for a small internal project, I’m a beginner and I would like to ask a small question.

I already understood how to bind simple model properties to nodes and link templates and also how to use conversion functions to translate a text into a color, like in this perfectly working case:

function nodeType2Color(type) { if (type === "BPOP") return "OrangeRed"; if (type === "BOMP") return "Peru"; return "white"; }

myDiagram.linkTemplate = $(go.Link, $(go.Shape, new go.Binding("stroke", "cabletype", cableType2Color)));

I’m asking if it’s possible to merge more than one property and pass it to a conversion function.
Suppose I have the following data for a node:

{"key":"ABC","label":"foo","type":"bar"}

And this simple merging function:

function mergeTexts(text1, text2) { return text1.concat(text2); };

How can I write a function that binds “label” and “type” to a new text to be used as a label (“foobar”, in this case) for the node or the link? The following try is (obviously) not working…

myDiagram.linkTemplate = $(go.Link, $(go.Shape, new go.Binding("text", "label", "type", mergeTexts)));

I hope I have explained well, English is not my main language.

Thanks in advance,
Guido

2

Use the empty string as the source property name, and the whole data object will be passed as the first argument to the conversion function.

  new go.Binding("text", "", function(data) { return data.label.concat(data.type); })

As the following documentation suggests, for efficiency reasons you should not use empty string source property name unless needed for this purpose. Binding | GoJS API

1 Like
3

Perfect, just what I was looking for… thank you very much, Walter!