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Can't add variable to waveform?

I'm working on a small demo project.  On my Nextion page, I've got a waveform control, a progress bar, a timer and a variable.

I started out trying to do this in the timer event:
  add 4,0,va0.val         //4 is the ID of the waveform control
...but the number added to the waveform always appears to be zero.

So then I tried (in the timer event):
  add 4,0,va0.val    //Also tried "add 4,0,j0.val", same result

With that code, I can see the progress bar increasing in value, but again the waveform just shows a flat line at the bottom.

It looks to me like the "add" command doesn't work with variables?  It would be nice to have that fixed if possible.

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I'm sorry, I've tested it, and it's really no good, we'll think of a way to update it in a later version. I hope you are patient. Thank you for your letter!

2 people like this
Hello ! Is this problem solved in Version V0.30 ? Thank You !
Bug is still in the latest version V0.31 :-(


BUG still exist in version 0.34.

Pleas Nextion DEV help us!

1 person likes this

I have the same problem.

Same problem in 0.36 :( any workarounds?

9 months are a very long time, solved the problem in 2016 ?

Devs promised to fix in the next release


Now I use 0.39. And cannot add value to waveform also.

It's always said: "Error: Invalid Variables: 0( Double click to jump to code)"

add 1, 0, h0.val

Waveform ID is 1, 1 channel.

h0 is a slider with min=0, max=255

Also tried which others options, but still cannot.


The current waveform implementation is expecting numeric values and cannot be parsed variable.


   add 1,0,0 ... add 1,0,37 ... add 1,0,255

The way it was implemented allows a connecting MCU to pass values, but not via Nextion variables.

Thanks for your reply.

But I tried with the number, also same error :(

Tu, You have spaces within your add command.

With the exception of the single space after add, there should be no other spaces.

This is a general rule for all commands - no embedded spaces within the parameters.

1 person likes this

Oopps, remove spaces and it works!

Great thanks! Sorry for silly question :P