Problem

When an attribute is not appearing in the diagram model (nodeArray), a different property should be selected

Ansatz – Approach

The third paramater of the Binding Constructor can be used to declare a function that handles the nodeData.

Lösung – Solution

// the node template describes how each Node should be constructed
      diagram.nodeTemplate =
        $(go.Node, "Auto",  // the Shape automatically fits around the TextBlock
          new go.Binding("location", "loc", go.Point.parse),
          $(go.Shape, "RoundedRectangle",  // use this kind of figure for the Shape
            // bind Shape.fill to Node.data.color
            new go.Binding("fill", "color")),
          $(go.TextBlock,
            { margin: 5, width: 100 },  // some room around the text
            // bind TextBlock.text to Node.data.key

            new go.Binding("text", "", 
              function(data) 
              { 
                return (data.text) ? data.text : data.key; 
              }
           ))
          );