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Change stimulus properties for a specific amount of time

Builder
#1

OS (e.g. Win10): Win10
PsychoPy version (e.g. 1.84.x): v2020.2.10
Standard Standalone? (y/n) If not then what?: yes
**What are you trying to achieve?:
Hi,

this seems like a rather simple question but I couldn’t really figure out how to do that:
I am trying to change the color of a polygon for 1 second after a valid mouse click.

What did you try to make it work?:

if mouse.isPressedIn(polygon_3):
   while XY 
        polygon_3.fillColor = 'yellow'

I have tried several code snippets for the placeholder XY. For instance using a timer, but then realized that a timer would add time to my time zero and create a time lag.

#2

I think you where on the right path with a timer. You could modify your code like this:

#in the begin routine tab
timer = core.Clock()
polygon_3.fillColor = 'white' #the color you want the polygon to normaly have

#in the each frame tab
if mouse.isPressedIn(polygon_3):
   timer.reset() #turn the timer back to 0
   polygon_3.fillColor = 'yellow'

if timer.getTime() >= 1:
   polygon_3.fillColor = 'white' #1 second after clicking on the polygon it becames white again

tandy

1 Like
#3

Hi tandy,

that makes so much sense. Thank you so much, it works perfectly. I guess I was a little confused with the timer function.

Thanks,

Kathrin

#4

Hi tandy,
after implementing that I ran into a new problem. I was trying to run this experiment on pavlovia but got an error message rearding to the core.Clock() function. After looking in the crib sheet I figuered I would have to implement the JS code. I tried this:

timer = new util.Clock();
for (var stim, _pj_c = 0, _pj_a = [Probe_Pos_1, Probe_Pos_2, Probe_Pos_3, Probe_Pos_4, Probe_Pos_5, Probe_Pos_6, Probe_Pos_7, Probe_Pos_8, Probe_Pos_9], _pj_b = _pj_a.length; (_pj_c < _pj_b); _pj_c += 1) {
    stim = _pj_a[_pj_c];
    stim.fillColor = "black";
    stim.lineColor = "black";
    }

But when I start it from the builder I get an Sytax error: invalid syntax.
Have you ever implemented this kind of code for an online study? and do you know if I can flexibly use pythin and JS code in the custom code components?

#5

Hello Kathrin

define the JavaScript timer in its own JS code-element. Leave the code-element that autotranslates Python to JavaScript untouched. Alternatively, you could set the code-element from autotranslate to both and edit the JavaScript part.

Best wishes Jens

1 Like
#6

Hi,

Thanks a lot! I already did that and it seems to be working in pavlovia. But now I can’t start it locally. Is it supposed to be like this? I mean it’s not a deal breaker, I could just test it online but maybe I’m doing something work.
Anyway, I’m sorry for all the questions, but I realized that my loop is also not working as soon as I switch to pavlovia. I have a condition sheet in which I define the opacity of every element. I broke my experiment down to only display the circles (3 trials, 10 seconds each). Instead of changing the opacity after 10 seconds, I get the same condition for 30 seconds. From the results file I can download I can see that I get only measurements for the first trial.
In my builder I set the opacity to change every repeat. Any idea where this error might come from?

Again, thanks a lot in advance!

Best,

Kathrin

#7

Hello Kathrin

well, it should work offline and online if you have set autotranslate to both or if you define two code-elements, one Python only, the other JavaScript only.

For the other problem, do you have a toy-experiment which exemplifies the problem?

Best wishes Jens

#8

So in the code component you have two windows, one for phyton (local) and one for javascript (online). For the experiment to work both online and offline you should have a working code in both windows. However if you are going to test your experiment online I think you can focus only on that.

For the changing opacity it is known that it gives some problem online. I suggest you to search the forum because I think there is a thread somewhere with a fix for this problem. Alternatively, you can change the color of the circles: if you want them to disappear for example you can change the fillcolor to the background color.

tandy

#9

Hi,

@tandy: thanks for the hint. It’s really a known issue. My work around is changing the colors for now and it seems to be working. The python -> JS crib sheet was really helpful.

@JensBoelte: It works since I used “both” and twisted the JS code according to the crib sheet. But I was wondering how to make the project on pavlovia public to be able to share it in this forum for example. I’m not sure if i’m missing something completely but I only found the members setting where I can add members to the project. I don’t have a licence or credits yet, but I thought there would be a way to share the project anyways.

Thank you so much!

Kathrin

#10

Hello

Open your project on gitlab, settings, permissions, public

Best wishes Jens

1 Like