I am a newbie in web development and tried my hand the following code:
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>A Generic Page </title>
<script type="text/javascript">
setTimeOut(wakeUpUser, 5000);
function wakeUpUser() {
alert("Time to make life interesting");
}
</script>
</head>
<body>
<h1>Just a generic heading </h1>
<p>Just a normal paragraph</p>
</body>
</html>
But the script does not run only a boring static HTML page.I am following the HeadFirst Javascript Programming.Is the book wrong on this example?
You have a typo in your JavaScript. setTimeout should be written with a small "o".
This is the Script error in your code, modify the "SetTimeout" to an actual case.
I have attached both the result of your code and Bug Fixed code results, where SetTimeout code fix suggested works fine.
setTimeout(wakeUpUser, 5000);
Your Code Before Fix:
Result After Bug Fix:
Just a super small typo in your code, instead of 'setTimeOut', it needs to be a lowercase 'O', so 'setTimeout'. Here's the complete snippet:
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>A Generic Page </title>
<script type="text/javascript">
setTimeout(wakeUpUser, 5000);
function wakeUpUser() {
alert("Time to make life interesting");
}
</script>
</head>
<body>
<h1>Just a generic heading </h1>
<p>Just a normal paragraph</p>
</body>
</html>
I think you much call setTimeout use o insteh of O after declare function :) ... If you don't have jQuery library. try to use setInterval function :) more exaple
http://www.w3schools.com/jsref/met_win_setinterval.asp
Try moving the setTimeout to be after the function is declared.
Your browser's developer tools should show you any errors encountered. Specifically the 'console'.
Happy coding!
Edit: see also the other answers about the small o in setTimeout
Related
I want to build a live Pythonn compiler similar to those at w3schools for Python, for some examples on my blog. I tried different approaches, and would like to hear different oppinions, but as of yesterday I'm trying to implement it using PyScript.
The documentation I found for PyScript doesn't help me a lot, as it seems like I can't understand it, or doing something wrong.
Here's the code that I'm trying to implement:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<title>Writing to the page</title>
<link rel="stylesheet" href="https://pyscript.net/latest/pyscript.css" />
<script defer src="https://pyscript.net/latest/pyscript.js"></script>
<textarea id="area1" rows="15">something</textarea>
<button onclick="myFunction()">Click me</button>
<py-script id="demo">
print("Hello, world!")
</py-script>
<py-terminal></py-terminal>
<script>
function myFunction() {
var text1 = document.getElementById('area1').value;
document.getElementById("demo").innerHTML = text1;
}
</script>
</body>
</html>
It just prints the content of the textarea above the terminal, without executing the code and printing the output, inside the terminal, as I imagined.
I'm expecting to make this functinal, and I tried a few things, but unsuccessfully.
I also tried:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<title>Writing to the page</title>
<link rel="stylesheet" href="https://pyscript.net/latest/pyscript.css" />
<script defer src="https://pyscript.net/latest/pyscript.js"></script>
<textarea id="area1" rows="15">print("something")</textarea>
<script>
let text1 = document.getElementById('area1').value;
</script>
<py-script>
def print_to_page(x):
exec(x)
</py-script>
<button py-click="print_to_page(text1)" id="print">Run!</button>
</body>
</html>
But I'm not sure how to pass the variable from JS to PyScript.
This 'Answer' is meant to help in addressing:
"I tried different approaches, and would like to hear different oppinions [sic],"
You may want to check out this post:
https://twitter.com/jtpio/status/1523660682708668416 May 2022
"The #SymPy Online Shell is now powered by the #pyodide stack and JupyterLiteš”
You can try the latest SymPy release directly in your browser, without installing anything, by visiting the following URL:
https://sympy.org/en/shell.html
Many thanks to Ivan Savov for leading this effort!"
Something like that may integrate well with your blog. You can hack around on it and hopefully put together what you need combined with that example and the documentation.
Related resources:
'Embedding the REPL on another website' section in the JupyterLite documentation
Embedding Jupyter Everywhere - Easily embed a console, a notebook, or a fully-fledged IDE on any web page.
Alternative approaches:
JupyterBook and MyST-NB seems to be moving along this route. For example see the Render option the left side there.
I'm not sure all the pieces are together but you can imagine with the JupyterLite/pyodide stuff it soon will be set for blogs.) Quarto may be heading that way, too.
See also Make Jupyter notebook executable in html format
Based on your description and the second example, it looks like you want to have a textarea where the user types in Python code, and run button that executes that entered code when clicked. If I've misunderstood your goal, you can disregard this answer.
The way to bring JavaScript objects/variables into Python is using Pyodide's import js syntax, which treats the JavaScript global namespace like a Python module. Here's a version very similar to your second example, which imports JavaScript's document object and uses that to extract the value of the textarea:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width,initial-scale=1" />
<title>Writing to the page</title>
<link rel="stylesheet" href="https://pyscript.net/latest/pyscript.css" />
<script defer src="https://pyscript.net/latest/pyscript.js"></script>
</head>
<body>
<textarea id="area1" rows="15">print("something")</textarea>
<py-script>
from js import document
def runTextInTag(id):
src = document.getElementById(id).value
exec(src)
</py-script>
<button py-click="runTextInTag('area1')" id="run">Run!</button>
</body>
To address your first example, which changes the innerHTML of the py-script tag itself: A <py-script> tag executes its contained code exactly once, when the custom element is attached to the DOM. This happens shortly after PyScript initializes and the custom HTML element <py-script> is defined, or when you add an additional <py-script> tag to the page.So, in your first example, setting the innerHTML/innerTEXT of a <py-script> tag does not cause that code to be executed again.
You could create a new <py-script> tag with the appropriate innerText and add it to the DOM, at which point its code would be executed, but I think the above method is cleaner for most purposes.
I have something simple. I have an html file and JavaScript file. In the JavaScript file the simple alert() function is called but, it does not work!
I wrote a second line in the JavaScript file to make sure I was not giving the incorrect path console.log() and it works as expected.
HTML:
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Demo</title>
</head>
<body>
<div id="container">
</div>
<script src="functionality.js"></script>
</body>
</html>
In external JavaScript file:
alert('hello'); // does not get executed
console.log( 'hello' ); // gets executed
Why this does not work?
You have probably pressed "prevent this page from creating additional dialog" in your Chrome browser. Try restarting it.
I'm new to programming. I'm trying to call a function in html, but it isn't working. What's the problem? Thanks in advance. (Don't ask about the whole integration thing).
My HTML code:
<!DOCTYPE html>
<html>
<head>
<script src="IntegrationCalculator.js"></script>
<script>
integrationCalculator(7);
</script>
</head>
<body>
<p id="tester">
Didn't work :(
</p>
</body>
My javascript code:
var integrationCalculator = function (variable1) {
if (variable1 = 7) {
document.getElementById("tester").innerHTML="WORKED";
}
};
Two things. First if (variable1 = 7) should be if (variable1 == 7). Second, call your function after the element is loaded in the DOM.
<!DOCTYPE html>
<html>
<head>
<script src="IntegrationCalculator.js"></script>
</head>
<body>
<p id="tester">
Didn't work :(
</p>
<script>
integrationCalculator(7);
</script>
</body>
jsFiddle example
integrationCalculator is called before the tester paragraph is created. Therefore, an error is thrown and the execution of the script is stopped.
I think I just need a second pair of eyes on this one. The div's onclick event doesn't seem to be working. Any ideas?
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title="My First Program"/>
<script type="text/javascript">
window.onload = function(){
window.alert("If you see me then the page has loaded");
click();
}
//we do programming here
/*because
it is
fun*/
window.alert("Helo World!");
function click(){
window.alert("CLICK!!!!");
}
</script>
</head>
<body>
<div>This web page will run my first program</div>
<!--this will be awesome-->
<br>
<br>
<br>
<div id="d1" onclick="click()">Click me</div>
</body>
Also, for the reccord, this is not my first program.
your html is malformed. the title tag needs to look like this:
<title>My First Program</title>
Also, you seem to have a naming conflict because you named your function the same thing as a built-in function. rename your 'click' function to 'myclick' or something else.
Once you fix that, everything else should be good.
When something is going weird, the first thing you should always do is validate your markup.
http://validator.w3.org/check
Here is the complete, working version of the markup.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>My First Program</title>
<script type="text/javascript">
window.onload = function(){
window.alert("If you see me then the page has loaded");
click();
}
//we do programming here
/*because
it is
fun*/
window.alert("Helo World!");
function myclick(){
window.alert("CLICK!!!!");
}
</script>
</head>
<body>
<div>This web page will run my first program</div>
<!--this will be awesome-->
<br>
<br>
<br>
<div id="d1" onclick="myclick()">Click me</div>
</body>
Every time I see a question like this anywhere, the typical answer I give is "don't use the Netscape model for event handling".
Give this a read - http://www.quirksmode.org/js/introevents.html
Update: Looks like "click" isn't a very good name for a function, since it's already registered for events and such, which is likely why it didn't work. I should have caught that.
OK guys this is intreting,
I'm testing this page
http://static.nemesisdesign.net/demos/ie8-strange/test.html
on IE8 / windows XP.
This is the code:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="content-language" content="en">
<title>Test</title>
</head>
<body>
<div id="thisgivesmeanerror">test</div>
<script>
thisgivesmeanerror = 'test';
alert('this alert won\'t be fired on my IE8, what about yours?');
</script>
</body>
</html>
If I open this page with IE8 I get an error.
If I change the code of the script to:
<script>
// note that I added var prefix
var thisgivesmeanerror = 'test';
alert('this alert won\'t be fired on my IE8, what about yours?');
</script>
It works fine.
This happens only on IE 7/8, didn't test it on IE6.
What do you think?
Does it happen to you also? Or is it just my browser that has gone crazy?
Addition
You're saying that is just not using the var prefix that cause the error?
I'm sorry guys but you're wrong, you didn't take time to test the code.
I uploaded a test2 page
http://static.nemesisdesign.net/demos/ie8-strange/test2.html
with the follwing cocde
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="content-language" content="en">
<title>Test 2</title>
</head>
<body>
<div id="thisgivesmeanerror">test</div>
<script>
thisdoesntgiveanyerror = 'test';
alert('This alert will be fired correcly');
</script>
</body>
</html>
That works fine.
So what is actually causing the error? The variable name without the var prefix having the same name as the ID of the DIV element.
Isn't this strange?
May be the answers to this SO-question can help?
You should always precede your variable declarations with var to specify their scope or you might observe inconsistent behavior between different browsers.
use var to declare variables instead of just plugging their name
I'd say the JavaScript interpreter in IE is slightly stricter than on FireFox and others, meaning the script returns an error when it comes to the variable definition line. Putting var in will ensure it actually is a variable.
It's very good practice to declare all your variables with var
James
EDIT
I can't get to IE at the moment, but I can recommend you change your <script> tag to <script type="text/javascript">.