Mysterious text component displays variable from previous trial

Online experiments
1

Hi,

I have a routine where the participant types freely to indicate the duration between two visual stimuli (i.e. before the “ms” in the screenshot below).

Untitled
Untitled1920×1080 28.2 KB

I use the code below in each frame to gather the user input in real-time:

L = event.getKeys();
    
if (L.length>0) {
    if ((allowedKeys.some(r=> L.includes(r))==true)) {
        userInput = userInput + L;
    } else if ((L.includes('backspace')==true)&&(userInput.length>0)) {
        userInput = userInput.substring(0,userInput.length-1);
    }
}

Issue: For each trial, the user input from the previous trial will flash for ~1 frame (in front of the “ms”) and then disappear. For trial 1, it’ll flash “undefined”. I reset userInput to empty after each trial, but it doesn’t seem to help.

The problematic text component is as below:

Untitled
Untitled707×867 49.7 KB

I was wondering why I see that flash at the beginning of each trial.
You may try out the task and see the issue using the link: masking_p2 [PsychoPy]

I’d really your help with troubleshooting this issue.
Thanks.

2

Your code component should be above your text component.

3

Yes, the code component is the very first component in that routine.

4

@wakecarter Any other reasons you can think of?
I should also mention this: I have the local version (PsychoPy) of the task as well. Same code, but no issue.

5

If resetting it in Begin Routine doesn’t work then try End Routine so it gets reset immediately after use.

Alternatively, set it to a space constant and then set in code with text_x.text =