The OmniGraffle 7.3 (Test) OmniJS documentation lists Canvas.background as a property, but attempts to access it raise error messages suggesting that the background is a shape which “has been removed”.
Context
Scripting access to the background is generally useful, not only for reading and setting graphic properties, but also for writing general meta info to canvas.background.notes.
(In my case, I am maintaining a JSON model of the structure of a hierarchical diagram, to allow for hierarchy-aware reformatting, and for some basic layouts not provided by the built-in Graphviz engine).
For reference, in JXA we can read and write to the canvas.background, including its notes property, in this pattern:
(() => {
'use strict';
const
og = Application("OmniGraffle"),
ds = og.documents,
d = ds.length > 0 ? ds.at(0) : undefined;
if (d) {
const
cnvs = d.canvases,
intCnv = cnvs.length,
cnv = intCnv > 0 ? cnvs.at(intCnv - 1) : undefined,
shps = cnv ? cnv.shapes : [];
cnv.canvasbackground.notes = "JSON\ntree model ...";
return cnv.canvasbackground.notes();
}
})();
