The situation : I use a script (a) in an HTML document to be able to use a particular SDK. Then I use a second script (b) basic to be able to create a Kendo UI table.
My problem : I try to pass data from script (a) to script (b) via global variables but it doesn't work, what can I do?
Info that might help you:
my document is a form framed by tags
I use Camunda. The first script allows me to use the SDK to retrieve the ID of the instance associated with the form being processed. (but I don't think this is the crux of the problem)
I assume that both scripts are read at the same time by the browser, and that's why script (b) can't read the variable simply because it is not yet created in script (a).
The code :
<script type="text/javascript" src="http://localhost:8080/camunda/app/tasklist/scripts/kendo.all.min.js"></script>
<script cam-script type="text/form-script">
var taskService = camForm.client.resource('task');
var processInstanceId = null;
var result = null;
taskService.get(camForm.taskId, function(err, task) {
//alert(JSON.stringify(task));
debugger;
processInstanceId = task.processInstanceId;
$.get("http://localhost:8080/engine-rest/process-instance/"+processInstanceId+"/variables", function(result) {
debugger;
window.alert("coucou");
console.log(result.JsonWeightSetpoints.value);
});
debugger;
console.log(result.JsonWeightSetpoints.value);
debugger;
});
</script>
<script type="text/javascript">
console.log(result.JsonWeightSetpoints.value);
//this is where I implement the Kendo UI grid
</script>
<div id="grid"></div>
I cannot read the content of the result variable in script (b) because it is not defined.
How do I do this?
Custom events solution:
<script type="text/javascript" src="http://localhost:8080/camunda/app/tasklist/scripts/kendo.all.min.js"></script>
<script cam-script type="text/javascript">
var taskService = camForm.client.resource('task');
var processInstanceId = null;
var result = null;
taskService.get(camForm.taskId, function(err, task) {
//alert(JSON.stringify(task));
debugger;
processInstanceId = task.processInstanceId;
$.get("http://localhost:8080/engine-rest/process-instance/"+processInstanceId+"/variables", function(result) {
debugger;
window.alert("coucou");
console.log(result.JsonWeightSetpoints.value);
// the value is available here, we now can trigger an event and send it
document.dispatchEvent(new CustomEvent("handler", {
detail: { value: result.JsonWeightSetpoints.value }
}));
});
debugger;
console.log(result.JsonWeightSetpoints.value);
debugger;
});
</script>
<script type="text/javascript">
console.log(result.JsonWeightSetpoints.value);
//this is where I implement the Kendo UI grid
// event listener, this would get executed only when we want
document.addEventListener("handler", function(event) {
// write you logic here
console.log(event.detail.value);
});
</script>
<div id="grid"></div>
useful resources:
MDN: Creating and triggering
events
Introducing asynchronous JavaScript
Let's say I have the following structure, just an example:
(function number1( $ ) {
$.fn.abcd = function( options ) {
heyyou.find(".123").css({});
heyyou.find(".456").css({});
var delay = 1000;
var site = "http://url";
setTimeout(function(){ window.location.href = site; },delay);}
$("#button").on('click', function(){ window.location.href = site;});
return this;
}( jQuery ));
And what I believe I need to do is something like this:
//part1
(function number1( $ ) {
$.fn.abcd = function( options ) {
heyyou.find(".123").css({});
heyyou.find(".456").css({});
return this;
}( jQuery ));
//part2
(function number1( $ ) {
$.fn.abcd = function( options ) {
var delay = 1000;
var site = "http://url";
setTimeout(function(){ window.location.href = site; },delay);}
$("#button").on('click', function(){ window.location.href = site;});
return this;
}( jQuery ));
What I'm trying to achieve here is:
"part1" is going to be inside a js file that's going to be placed inside the header. "part2" is a function that I need to call from a <script></script> later on the DOM.
The thing is that both parts are using the same main function, one is continuing the other.
For example:
<script src="part1.js"></script>
<body>
<script>//part2</script>
<button id="button">Do something</button>
</body>
So basically I want the function to start in the js file, then I'll finish it from another part. I'm not sure how to explain this, it's just that I need the var site to be called separately, as I'm going to use the same script for different pages, I need each page to call for the var site with a different value.
Basically it's a redirect script, so I can't use the same redirection url for every page.
EDITED:
The structure needs to be like this:
mainjs.js:
<header>
<script>
//part1
(function number1( $ ) {
$.fn.abcd = function( options ) {
heyyou.find(".123").css({});
heyyou.find(".456").css({});
return this;
}( jQuery ));
</script>
</header>
Page 1:
//part2
var site google
Page 2:
//part2
var site bing
Page 3:
//part2
var site yahoo
"//Part1" is executed first and is executed in every page.
"//part2" is executed later and each page will have a different url to redirect to, inside "//part2" function.
In reply to Ehsan:
It would have to be like this:
<script type="text/javascript" >
function function1(site) {
//redirect to site
alert(site);
}
</script>
<script type="text/javascript" >
function function2() {
// Do your css thing here.
site = "http://somethingelse";
function2(site);
}
</script>
<button onclick="function2()">Click me</button>
Edit - 3
You are looking for something like this.
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function() {
alert(site);
});
</script>
<script type="text/javascript">
var site = "google.com";
</script>
You can create two separate functions, chain them and use global variables to pass the data between them.
<script type="text/javascript" >
var site = "http://url";
function function1() {
// Do your css thing here.
site = "http://somethingelse";
function2();
}
</script>
<button onclick="function1()">Click me</button>
<script type="text/javascript" >
function function2() {
//redirect to site
alert(site);
}
</script>
Edit: You can also pass data by using parameter in function, then you don't need to use the global parameter. It depends on the use case, but I assume passing as a parameter is a much cleaner option.
<script type="text/javascript" >
function function1() {
// Do your css thing here.
site = "http://somethingelse";
function2(site);
}
</script>
<button onclick="function1()">Click me</button>
<script type="text/javascript" >
function function2(site) {
//redirect to site
alert(site);
}
</script>
I wanted to call a function defined in a first.js file in second.js file. Both files are defined in an HTML file like:
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
I want to call fn1() defined in first.js in second.js. From my searches answers were if first.js is defined first it is possible, but from my tests I haven't found any way to do that.
Here is my code:
second.js
document.getElementById("btn").onclick = function() {
fn1();
}
first.js
function fn1() {
alert("external fn clicked");
}
A function cannot be called unless it was defined in the same file or one loaded before the attempt to call it.
A function cannot be called unless it is in the same or greater scope then the one trying to call it.
You declare function fn1 in first.js, and then in second you can just have fn1();
1.js:
function fn1 () {
alert();
}
2.js:
fn1();
index.html :
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
You could consider using the es6 import export syntax. In file 1;
export function f1() {...}
And then in file 2;
import { f1 } from "./file1.js";
f1();
Please note that this only works if you're using <script src="./file2.js" type="module">
You will not need two script tags if you do it this way. You simply need the main script, and you can import all your other stuff there.
1st JS:
function fn(){
alert("Hello! Uncle Namaste...Chalo Kaaam ki Baat p Aate h...");
}
2nd JS:
$.getscript("url or name of 1st Js File",function(){
fn();
});
You can make the function a global variable in first.js
and have a look at closure and do not put it in document.ready put it outside
you can use ajax too
$.ajax({
url: "url to script",
dataType: "script",
success: success
});
same way you can use jquery getScript
$.getScript( "ajax/test.js" )
.done(function( script, textStatus ) {
console.log( textStatus );
})
.fail(function( jqxhr, settings, exception ) {
$( "div.log" ).text( "Triggered ajaxError handler." );
});
declare function in global scope with window
first.js
window.fn1 = function fn1() {
alert("external fn clicked");
}
second.js
document.getElementById("btn").onclick = function() {
fn1();
}
include like this
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
use "var" while creating a function, then you can access that from another file. make sure both files are well connected to your project and can access each other.
file_1.js
var firstLetterUppercase = function(str) {
str = str.toLowerCase().replace(/\b[a-z]/g, function(letter) {
return letter.toUpperCase();
});
return str;
}
accessing this function/variable from file_2.js file
firstLetterUppercase("gobinda");
output => Gobinda
It should work like this:
1.js
function fn1() {
document.getElementById("result").innerHTML += "fn1 gets called";
}
2.js
function clickedTheButton() {
fn1();
}
index.html
<html>
<head>
</head>
<body>
<button onclick="clickedTheButton()">Click me</button>
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
</body>
</html>
output
Try this CodePen snippet: link .
Please note this only works if the
<script>
tags are in the body and NOT in the head.
So
<head>
...
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
</head>
=> unknown function fn1()
Fails and
<body>
...
<script type="text/javascript" src="first.js"></script>
<script type="text/javascript" src="second.js"></script>
</body>
works.
This is actually coming very late, but I thought I should share,
in index.html
<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>
in 1.js
fn1 = function() {
alert("external fn clicked");
}
in 2.js
fn1()
Use cache if your server allows it to improve speed.
var extern =(url)=> { // load extern javascript
let scr = $.extend({}, {
dataType: 'script',
cache: true,
url: url
});
return $.ajax(scr);
}
function ext(file, func) {
extern(file).done(func); // calls a function from an extern javascript file
}
And then use it like this:
ext('somefile.js',()=>
myFunc(args)
);
Optionally, make a prototype of it to have it more flexible. So that you don't have to define the file every time, if you call a function or if you want to fetch code from multiple files.
first.js
function first() { alert("first"); }
Second.js
var imported = document.createElement("script");
imported.src = "other js/first.js"; //saved in "other js" folder
document.getElementsByTagName("head")[0].appendChild(imported);
function second() { alert("Second");}
index.html
<HTML>
<HEAD>
<SCRIPT SRC="second.js"></SCRIPT>
</HEAD>
<BODY>
method in second js<br/>
method in firstjs ("included" by the first)
</BODY>
</HTML>
window.onload = function(){
document.getElementById("btn").onclick = function(){
fn1();
}
// this should work, It calls when all js files loaded, No matter what position you have written
});
// module.js
export function hello() {
return "Hello";
}
// main.js
import {hello} from 'module'; // or './module'
let val = hello(); // val is "Hello";
reference from https://hype.codes/how-include-js-file-another-js-file
My idea is let two JavaScript call function through DOM.
The way to do it is simple ...
We just need to define hidden js_ipc html tag.
After the callee register click from the hidden js_ipc tag, then
The caller can dispatch the click event to trigger callee.
And the argument is save in the event that you want to pass.
When we need to use above way ?
Sometime, the two javascript code is very complicated to integrate and so many async code there. And different code use different framework but you still need to have a simple way to integrate them together.
So, in that case, it is not easy to do it.
In my project's implementation, I meet this case and it is very complicated to integrate. And finally I found out that we can let two javascript call each other through DOM.
I demonstrate this way in this git code. you can get it through this way. (Or read it from https://github.com/milochen0418/javascript-ipc-demo)
git clone https://github.com/milochen0418/javascript-ipc-demo
cd javascript-ipc-demo
git checkout 5f75d44530b4145ca2b06105c6aac28b764f066e
Anywhere, Here, I try to explain by the following simple case. I hope that this way can help you to integrate two different javascript code easier than before there is no any JavaScript library to support communication between two javascript file that made by different team.
<html>
<head>
<link rel="stylesheet" type="text/css" href="css/style.css" />
</head>
<body>
<div id="js_ipc" style="display:none;"></div>
<div id="test_btn" class="btn">
<a><p>click to test</p></a>
</div>
</body>
<script src="js/callee.js"></script>
<script src="js/caller.js"></script>
</html>
And the code
css/style.css
.btn {
background-color:grey;
cursor:pointer;
display:inline-block;
}
js/caller.js
function caller_add_of_ipc(num1, num2) {
var e = new Event("click");
e.arguments = arguments;
document.getElementById("js_ipc").dispatchEvent(e);
}
document.getElementById("test_btn").addEventListener('click', function(e) {
console.log("click to invoke caller of IPC");
caller_add_of_ipc(33, 22);
});
js/callee.js
document.getElementById("js_ipc").addEventListener('click', (e)=>{
callee_add_of_ipc(e.arguments);
});
function callee_add_of_ipc(arguments) {
let num1 = arguments[0];
let num2 = arguments[1];
console.log("This is callee of IPC -- inner-communication process");
console.log( "num1 + num2 = " + (num1 + num2));
}
better late than never
(function (window) {const helper = { fetchApi: function () { return "oke"}
if (typeof define === 'function' && define.amd) {
define(function () { return helper; });
}
else if (typeof module === 'object' && module.exports) {
module.exports = helper;
}
else {
window.helper = helper;
}
}(window))
index html
<script src="helper.js"></script>
<script src="test.js"></script>
in test.js file
helper.fetchApi()
I have had same problem. I have had defined functions inside jquery document ready function.
$(document).ready(function() {
function xyz()
{
//some code
}
});
And this function xyz() I have called in another file. This doesn't working :) You have to defined function above document ready.
TLDR: Load Global Function Files first, Then Load Event Handlers
Whenever you are accessing an element within a JS file or <script> block, it is essential to check to make sure that element exists, i.e., jQuery's $(document).ready() or plain JS's document.addEventListener('DOMContentLoaded', function(event)....
However, the accepted solution does NOT work in the event that you add an event listener for the DOMContentLoaded, which you can easily observe from the comments.
Procedure for Loading Global Function Files First
The solution is as follows:
Separate the logic of your JS script files so that each file only contains event listeners or global, independent functions.
Load the JS script files with the global, independent functions first.
Load the JS script files with event listeners second. Unlike the other previous files, make sure to wrap your code in document.addEventListener('DOMContentLoaded', function(event) {...}). or document.Ready().
If I have this code in a file called custom.js:
var kennel = function(){this._init();};
kennel.prototype = {
_init: function() {
this.setListeners();
},
setListeners: function(){
...
},
getCats: function(){
alert("Get cats");
}
};
How do I call getCats() from some arbitrary html file?
First of all you would include the javascript by using the <script> tag, generally in the <head>, then after that you can create another <script> tag which you can place your own javascript code in that is specific to the page, and which uses the functionality made available by the included file. For example:
<head>
<script type="text/javascript" src="path/to/custom.js"></script>
<script type="text/javascript">
var myKennel = new kennel();
myKennel.getCats(); // alerts "Get cats"
</script>
</head>
Also, the code you have posted has nothing to do with jQuery - it is plain old, vanilla javascript.
This should be enough:
<script>
var k = new kennel();
k.getCats();
</script>
Here's a sample of it working: http://jsfiddle.net/NHaBb/
I have two web page(a.php & b.php). They have very similar logic but distinct UI. I wrote two javascript.
They both look like:
aUI = {
displayMessage = function ...
showDetails = function ...
}
function foo() {
aUI.displayMessage();
aUI.showDetails();
// and other things about aUI.displayMessage() and aUI.showDetails()...
}
foo();
aUI.displayMessage() is different from bUI.displayMessage(). But a.js and b.js have the same foo().
I extracted foo(). So now I have three .js: aUI.js, bUI.js and logic.js.
logic.js:
function foo() {
UI.displayMessage();
UI.showDetails();
//other things about UI
}
foo();
aUI.js and bUI.js:
UI = {
displayMessage = function ...
showDetail = function ...
}
How can a.php know it should use aUI.js? I wrote the plain implement:
<script type="text/javascript" src="aUI.js"></script>
<script type="text/javascript" src="logic.js"></script>
It works but seems not clever. I have duplicated namespace 'UI' in a project.
Is there a better way?
What about this?
aUI.js and bUI.js have there own namespace like aUI and bUI.
And add some more code like this:
<script type="text/javascript" src="aUI.js"></script>
<script type="text/javascript">
var UI = aUI;
</script>
<script type="text/javascript" src="logic.js"></script>
This approach resolves the problem about duplicated namespace 'UI'. I think this is kind of DI.
This sounds like a classic problem to be solved by inheritance. You can do this any number of ways in javascript. Here are a few examples.
Classical inheritence: http://www.crockford.com/javascript/inheritance.html
Prototypal inheritence: http://javascript.crockford.com/prototypal.html
dojo.declare: http://docs.dojocampus.org/dojo/declare *
If you did this in Dojo, for example, it would look like this
ui-base.js
dojo.declare("_UI", null, {
displayMessage: function() { },
showDetails: function() { },
foo: function() {
this.displayMessage();
this.showDetail();
}
});
ui-a.js
dojo.declare("UI", _UI, {
displayMessage: function() { /* Override and define specific behavior here */ },
showDetails: function() { /* Override and define specific behavior here */ }
});
ui-b.js
dojo.declare("UI", _UI, {
displayMessage: function() { /* Override and define specific behavior here */ },
showDetails: function() { /* Override and define specific behavior here */ }
});
Then, in your PHP, you just include the appropriate javascript files
a.php
<script src="ui-base.js"></script>
<script src="ui-a.js"></script>
b.php
<script src="ui-base.js"></script>
<script src="ui-b.js"></script>
* The world has too many jQuery examples to make yet another, so you get Dojo this time around ;)
The solution is to architect your code that you don't need to do this and duplicate code.
But if you want to stick with it then you can create a file called logic.php and inside do something like this
header("Cache-Control: no-cache");
$currentScript = reset(explode(".", end(explode("/", $_SERVER["SCRIPT_NAME"]))));
read_file("scripts/" . $currentScript . ".js");
echo "\n;\n";
read_file("scripts/logic.js");
and in html
<script type="text/javascript" src="logic.php"></script>
this way the script will change it's content because it will concatenate the required script based on it's name and the content of logic.js. The downside of this is thatit invalidates the caching of the browser.
Another solution will be to synchronously load in logic.js the other module you need. You can get the name of the script from document.location.href