Update host on AudioProcessorValueTreeState state change



I’ve notice that if you directly modify an AudioProcessorValueTreeState’s state (not via a parameter), then the host is never notified of the change. In the case of Ableton Live, if you save your track, then modify the ValueTree, the host’s save option is still greyed out. Is there any way to update the host to notify of a change? I’ve tried updateHostDisplay(), which didn’t do the trick. Here’s an example of what I mean:

valueTreeState.state.setProperty("customProperty", "Some non parameter value", nullptr);



Have you solved this thing?
I have this issue now.
How can I notify the host of value changes when modifying a value of AudioProcessorValueTreeState’s state directly?

Thank you


Hi there, i have the same issue, did both of you solved the issue or found a trick to do it ?

Thanks a lot


You can call AudioProcessor::updateHostDisplay() directly to mark the state as dirty.
After that the save option should be enabled.

Hope that helps


Using updateHostDisplay() does not seem to do anything in Ableton Live. Has anyone found a viable solution to this, other than tweaking a parameter?


I don’t remember about this well.

I guess I added dummy parameter then updated it like below.