Value_change of dependent rollers crash SquareLine Studio

What do you want to achieve?

I’d like to link two rollers together.

What have you tried so far?

I created two rollers, connected an event on one roller so that roller1 VALUE_CHANGED sets roller2. When I run the UI, I can move roller1 one time, then it no longer moves, and SLS crashes out shortly(may require pausing UI).

Edit: I think I figured this out - my event was setting roller2’s property to a blank field. If I set it to a number, then it doesn’t crash. If I set it to something other than a number, then the UI crashes after executing it.

Minimal project that triggers this: (8.5 KB)


  • SquareLine Studio version: 1.3.2
  • Operating system: Windows 11
  • Target hardware: None.

Hi, unfortunately, you will not be able to solve this in the software so that it works automatically. The easiest way to do this is to put an event on the roller whose trigger is a value change and a call function action. You can then write custom code in the exported ui_events.c.

@SquareLine_Support , thank you for the design guidance on how to link the rollers together - that makes sense, and we’ll do a lot more plumbing this way.

However, I’d still like to ask that SLS not crash out if the UX engineer ever makes a mistake like running the simulator using the default property value, which is blank(NULL I presume).

1 Like