Getting an LC error when trying to talk to Javascript

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Opaquer
Posts: 247
Joined: Wed Aug 14, 2013 8:24 am

Getting an LC error when trying to talk to Javascript

Post by Opaquer » Sun Jun 21, 2020 4:28 pm

Hey guys!

EDIT: Post has been solved - see post #4 for the solution. Leaving this up here in case someone else has an error 859 in future with their LC browser! GL everyone!

So, a little while ago I got started on making an app to help with sudokus, and after a few setbacks, decided to put it on the shelf for a bit. Well, with everything that's happening I decided to take it off the shelf and give it a another shot - hopefully while being more successful than last time!

Basically, I have some JS code that can solve a sudoku very quickly, and I got it all working in JS as far as I can tell (I don't actually know much JS, so I've just been working my way through it trying to get it to work, but when I made it into an .html file and ran it in my browser, it did what it was supposed to). Unfortunately when I then go to get LC to communicate with the code I have, I get an error (see picture below).

I thought I was doing something wrong, so decided to start a new stack with the absolute basics of what I thought was needed to make LC and JS communicate just as a proof of concept. I have a field "HTMLText", which lets me paste in HTMLText to use in the browser, and widget "Browser" (very original name, I know!), a button "Button", and a field "Output" to get the output printed in there. Here's my code:

In my "HTMLText" field, I have this:

Code: Select all

<html><head><script type="text/javascript">
function solve(a)
{
	var b=5;
	var c;
	c=a+b;
	livecode.Test(c);
}
</script></head></html>
In theory what I want it to do is take a number from LC, add b (in this case, 5, though in future tests I may want multiple inputs/outputs), then spit it out into my Output field. Test is the handler I've set up in LC that JS will call out for.

My Button code is as follows:

Code: Select all

on mouseup
   put "" into field "Output"
   set the HTMLText of widget "Browser" to field "HTMLText"
   do "solve(5);" in widget "Browser" 
end mouseup
And finally, my card code

Code: Select all

on Test c
   put c into field "Output"
end Test
I've tried setting the javascriptHandlers through code and through the property inspector of my browser and still end up with the same result.

When I run it, I expect it to come back with 10 in the output field, but I get the error below.

Annoyingly enough, I've had this error before last time I was working on the app, and while I can't remember exactly how I fixed it, I think I changed LC versions and it worked. However that isn't working that time around, so not sure if there's something else I'm missing with it. For reference, I have LC Indy 9.6, LC Community 9.6 dp2 and LC Community 9.5.1. I'm also using a new laptop with Windows 10 on it.

If anyone knows this error or how to fix it, I would appreciate it greatly! I'd like to think that once it's fixed I'll be very close to finishing my app, but you know how programming is - once this gets fixed, there'll probably be another 37 issues I'll need to fix up before I can even find the next lot of bugs in it!

If you guys need any more info or for me to test anything, just let me know!

Many thanks!
Attachments
Error.png
Error.png (11.63 KiB) Viewed 14840 times
Last edited by Opaquer on Mon Jun 22, 2020 4:03 pm, edited 1 time in total.

Thierry
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Posts: 875
Joined: Wed Nov 22, 2006 3:42 pm

Re: Getting an LC error when trying to talk to Javascript

Post by Thierry » Sun Jun 21, 2020 5:22 pm

Hi Opaquer,

Code: Select all

on mouseup
   put "" into field "Output"
   set the HTMLText of widget "Browser" to field "HTMLText"
   do "solve(5);" in widget "Browser" 
end mouseup
Out of my head,
I would give some times for the widget to be set.

Code: Select all

on mouseup
   put "" into field "Output"
   set the HTMLText of widget "Browser" to field "HTMLText"
   send "doSolve" to me in 1 seconds -- check for the right time
end mouseup

on doSolve
   do "solve(5);" in widget "Browser" 
end doSolve
or do your widget settings in the openstack, opencard,...

HTH,

Thierry
!
SUNNY-TDZ.COM doesn't belong to me since 2021.
To contact me, use the Private messages. Merci.
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Opaquer
Posts: 247
Joined: Wed Aug 14, 2013 8:24 am

Re: Getting an LC error when trying to talk to Javascript

Post by Opaquer » Mon Jun 22, 2020 2:44 am

Hi Theirry

Thanks for the input and the advice - I didn't give it much time to load everything up before!

I changed the code for the button to what you said and gave it a shot, and unfortunately I still got the same error :(

Thierry
VIP Livecode Opensource Backer
VIP Livecode Opensource Backer
Posts: 875
Joined: Wed Nov 22, 2006 3:42 pm

Re: Getting an LC error when trying to talk to Javascript

Post by Thierry » Mon Jun 22, 2020 8:11 am

Opaquer wrote:
Mon Jun 22, 2020 2:44 am
Hi Thierry
Thanks for the input and the advice
I changed the code for the button to what you said and gave it a shot,
and unfortunately I still got the same error :(
Hi Opaquer,

Sorry, don't have other ideas, but feel free to send me your testing stack,
I might look at it...

Regards,

Thierry
!
SUNNY-TDZ.COM doesn't belong to me since 2021.
To contact me, use the Private messages. Merci.
!

Opaquer
Posts: 247
Joined: Wed Aug 14, 2013 8:24 am

Re: Getting an LC error when trying to talk to Javascript

Post by Opaquer » Mon Jun 22, 2020 4:03 pm

Hey everyone!

I just wanted to give an update to this topic: Thierry and I had a look through some code, and he did his thing of being absolutely amazing when it comes to LC related things. Turns out in my JS code, I had:

Code: Select all

livecode.Test(c);
when what it should be is

Code: Select all

liveCode.Test(c);
That silly capital! Anyway, I just wanted to post this in case anyone else runs into this problem in the future!

Happy coding everyone!

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