sliderValueChanged() not called when using automation


#1

Hello,
Here’s my first (dumb) question on this forum.
I’m trying to code an audio application. The problem I have is that the sliderValueChanged() is called only when I move a parameter by hand, the automation doesn’t call it.
On the other hand the UI follows the automation without problem… Is there a specific method that I would have forgot to implement that could lead to this situation?
(Juce 2.0.27, built with Juce 2.0.28, the VST simply crashes the host at startup…)
Thanks by advance,
Matthieu


#2

Well a slider will only update when you give it a new value, it won’t magically know when a parameter is changed - you’d need to call its setValue method to tell it.

Care to give more info, a stack trace, etc?


#3

Thanks, it was even worse : I browsed my code for a few hours, looking in the parts I’m not sure to fully understand what they are supposed to do (first audio plugin) and realized that I had simply instantiated the slider with “dontSendNotification”…
Sorry for the noise!
I’ll try to send you more info about the crashes tomorrow.


#4

Ok, I post a new reply here even if the problem is slightly different : I thought I had finished my plugin because during my tests everything was working fine, but when I tried to use it in a real project I realized I had a new problem : everything is working fine till my vst is visible but when I close the GUI to use it exclusively with the automation nothing work… when I reopen it, the sliders restart to follow the automation and the sliderValueChanged() method is called and it restarts sending OSC messages (the goal of the plugin)… Can someone point me a direction to fix this?
All the best,
Matthieu
PS : For the 2.0.28 problem, I guess it came from my code since I use it now without problem.


#5

Sounds like a problem in your implementation. Presumably you’ve hacked it so that your sliders are somehow involved in the automation process - you need to be careful to keep your UI separate from your actual processing algorithms.


#6

Thanks for your quick reply Jules!
Indeed the osc messages are totally relying on the sliders setup (range + steps), so if I understand you well I must absolutely not rely on any GUI component for my messages, let’s say I have to use the parameter value [0.;1.] in my AudioProcessor then hack it so it reflects what I’ve setup for my sliders? I realize that if I’m right, I have to rewrite my whole plugin! Ok, I’ll try to figure out how I can do this.
Thanks again!