Add a button on gridlines diagram at a fixed location

GoJS
#1

How can i add a button on a gridlines diagram at a fixed location as shown in the following diagram:

image.png806×505 17.9 KB

Thanks.

#2

See this section of the intro: GoJS Legends and Titles -- Northwoods Software. It goes over how to add a static part.

#3

Thanks @jhardy! “Static Parts” helped me here.