Stop selection change or deletion

GoJS
1

I am using the Tree Layout and model.

When a node is selected, just like the org sample, we have a object properties viewer (in html/angular).
A user can make changes to properties causing validation errors. While in error we want to deny certain actions on the graph:

  • deny selection changing
  • deny deletion (i believe i can use ‘canDeleteSelection’)

I cannot seem to find a way to cancel selection changing.

2

Have you tried setting Diagram.allowSelect to false?

And try setting Diagram.allowDelete to false, to prevent people from deleting the currently selected part(s).

More information is at GoJS User Permissions -- Northwoods Software

3

That works.

4

Is there another option apart from Diagram.allowSelect?

This works fine, but not very clear to the user why he cant click on stuff.
I would rather that when he clicks to select - i give me a message telling him errors and in the same instance stop his selection.

really back to - is there a way to cancel the selection changing?

5

Well, for simple clicks and rubber-band drags you could override the Tool.standardMouseSelect method of the ClickSelectingTool to do what you want.

However there are other tools that can select or de-select, so those would all have to put up a message and be disabled too. Those include the DraggingTool and LinkingTool and ContextMenuTool and perhaps others. So that would be a lot of tools that would need method overriding (or simple disablement by setting Tool.isEnabled to false).
https://gojs.net/latest/intro/tools.html

Furthermore the CommandHandler.selectAll command would still work, so you would need to override CommandHandler.doKeyDown in order to make Ctrl/Cmd-A put up a message and be a no-op.
https://gojs.net/latest/intro/commands.html#CommandHandler

6

Yikes,
Thanks for the info.