How to know if javascript is executing?

**Contours** · 04 October 2016, 02:24 PM

There are several references on this forum to modifying a page's behavior by placing html of the following form in the body of a page:

Although I've following the "instructions" for using it, I have seen no evidence that it actually works or is even executing ... which leads me to these questions:

Is there a statement I can add to that block that would display a message or change a color ... or something?
xr_v1 appears to be a function. Where might I find it documented?
When such a script is in the body html, when is it executed?

As you can tell, I'm not versed in javascript. And it's tough to get even a toehold when viewing resources like W3School. But I'm trying to learn.

Thanks in advance for any assistance.

**Egg Bramhill** · 05 October 2016, 12:09 AM

I normally follow siran or Acorn when it comes to JS Contours, I just dabble (badly).

However copy the following text, paste it into Notepad, save it as test.html & run it in a browser.

<html>
<body>

<p id="p1">What's your name?</p>
<button type="button" onclick="myFunction()">Answer</button>
<p><p/>
<button type="button" onclick="myFunction2()">Reset</button>

<script>
function myFunction() {
document.getElementById("p1").innerHTML = "Contours";
document.getElementById("p1").style.color = "blue";
}

function myFunction2() {
document.getElementById("p1").innerHTML = "What's your name?";
document.getElementById("p1").style.color = "red";
}
</script>

</body>
</html>

Getting that to work in Xara isn't within my knowledge.

**Contours** · 05 October 2016, 01:05 AM

@Egg: Thanks for that sequence. It's easy to follow what it does when opened in a browser. It's certainly a good start.

As a test, I named one of the page's text fields "text" and made a crude attempt at grafting one statement into the snippet in the page body ... without any result.

If it's even possible to do this, maybe someone can correct my syntax error(s).

I appreciate your help.

**Egg Bramhill** · 05 October 2016, 01:52 PM

Don't know how you attach the code to Xara Buttons but this works with html generated buttons.

**Contours** · 05 October 2016, 07:39 PM

Yes, it does work as you've described. But when I attempted to adapt a single statement into a super-simple test case:

... nothing changed. I suspect I'm not in the right ballpark with the syntax.

Thanks for posting the example. I'll continue to look for other examples of "body html" to get a handle on uses.

**Egg Bramhill** · 05 October 2016, 09:17 PM

[QUOTE]<script>document.getElementById("text").style.co lo r = "red"</script>[/QUOTE

Try

document.getElementById("text").style.color = "red";

thats without the gap between the o and r in color and the semicolon on the end.

**Scotty** · 05 October 2016, 10:17 PM

Seems to me the original insert
that you have a space in 'colo r' maybe not picking that script up due to the space..
Jim

**Contours** · 05 October 2016, 10:33 PM

@Scotty: those occasional blanks are inserted by the forum software ... to keep text strings from being too long to wrap, I believe.

@egg: I got the result shown below. In a way, it gives a hint as to how the body html is interpreted. I'm still at a loss of how to get it to tell the browser that I want a different result than what is defined in the xara-built html. Am I looking at this all wrong? If I am, how do scripts in the body html modify elements like slider widgets?

Thanks for the responses.