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I have this very simple program:

n=0;
{
Button["Play", a = RandomInteger[10];b = RandomInteger[10];n+=1 ],
Dynamic[a], "vs", Dynamic[b], "draw number:", Dynamic[n]
}

When I run it, only the first variable visually updates in the output line. If I ask for the value of b or n, I can see that they do change every time, but it is not dynamically visible. This is a big problem for me. Is it ab browser issue? Sometimes the b gets updated, sometimes not...

what it looks like when I run it

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  • $\begingroup$ I see both a and b update, so I don't know what trouble you're having with b. But n was never given a value, so n+=1 can't actually have an effect. You need to initialize n to some value . $\endgroup$
    – lericr
    Apr 26, 2023 at 18:27
  • $\begingroup$ sorry yes. in my notebook I sent n=0 before I run this. Could it be like a browser issue? is there a recommended browser to run Wolfram-cloud? $\endgroup$ Apr 26, 2023 at 18:34
  • $\begingroup$ I tried switching a and b in the dynamic at the Bottom, and still only a gets updated when I click the button. $\endgroup$ Apr 26, 2023 at 18:44
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    $\begingroup$ Indeed. I just tried in in wolframcloud (using Safari), and I see the behavior you're describing. $\endgroup$
    – lericr
    Apr 26, 2023 at 19:00
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    $\begingroup$ Hello user3447795, I think it would make sense to mention in the question or even the title that you encounter this problem in the cloud only. That will avoid a lot of people trying this and not seeing the problem. I think the majority of readers here will typically still use the desktop version... $\endgroup$ Apr 28, 2023 at 20:36

1 Answer 1

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It looks like it might be a "limitation" of the cloud version... although it sometime actually work for a short moment. I did, however, find a work around:

n=0;
{
Button["Play", a = RandomInteger[10];b = RandomInteger[10];n+=1 ],
Dynamic[a], "vs", Dynamic[b+a-a], "draw number:", Dynamic[n+a-a]
}

The first variable that gets dynamically computer refresh, so if we use it in the other Dynamic[] functions, they refresh "as expected"...

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