detect element where the function was called from - javascript

I need to know where my jQ function was called from...
In head:
function call_pl2(){
$(this).text('some text');
}
in Body:
<p> <script> call_pl2(); </script> </p>
<!-- OR -->
<div> <script> call_pl2(); </script> </div>

I got your point, I'm afraid you cannot get from the function the element that your js function is there, but each time that your function is called you can use another function and search your html content to see where this function is inside. I assume that this function is called ones from the html code when this is loaded.

Instead of trying to determine which element contains the the script tag (and, by extension, a particular call to call_pl2()) you could explicitly pass the containing element to call_pl2() as a parameter:
$(function() {
var call_p12 = function(element) {
if ($(element).is('p')) {
$(element).text('here is some text added to a paragraph');
}
if ($(element).is('div')) {
$(element).text('here is some text added to a div');
}
}
$('div, p').each(function() {
call_p12($(this));
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<p></p>
<div></div>
It would be relatively easy to modify the call_p12() function to swap in a more specific selector in the jQuery is(). For example is('.someclass') to check for a class value instead of a tag name.

Related

Toggle hide/show not working on childs div

I have a script that gets data from a Google Sheet and displays it as a webpage - using JS and Tabletop.js.
There are multiple entries in the Sheet thus multiple entries in the webpage. To organise the Data I have a hide/show button. When the button is clicked on the first entry it works. However when the any of the other buttons are clicked it hides or shows the first entries data, not its own!
How do I hide/show each individual entries data? Below is the code I am working with!
I am new to JavaScript - Thanks in advance!
P.S - I struggled writing the Title to the questions!
<link href="../common/cats-copy.css" media="screen" rel="stylesheet" type="text/css" />
</head>
<style>
#add-info {
display: none
}
</style>
<body>
<div class="container">
<h1>Resturants</h1>
<div id="content"></div>
<script id="cat-template" type="text/x-handlebars-template">
<div class="entry">
<h5>{{establishment_name}}</h5>
<h6>Area: {{area}}</h6>
<h6>Cuisine: {{cuisine}}</h6>
<button id="btn" class="button-primary" onclick="myFunction()">Hide</button>
<div id="add-info">
<h6>Address: {{address}}</h6>
<h6>Google Maps: {{google_maps_location}}</h6>
<h6>Opening Times: {{opening_times}}</h6>
<h6>Rating: {{rating}}</h6>
<h6>Added By: {{added_by}}</h6>
<h6>Date Added: {{date_added}}</h6>
</div>
</div>
</script>
</div>
<!-- Don't need jQuery for Tabletop, but using it for this example -->
<script type="text/javascript" src="handlebars.js"></script>
<script type="text/javascript" src="../../src/tabletop.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script type="text/javascript">
var public_spreadsheet_url = 'https://docs.google.com/spreadsheets/d/1h5zYzEcBIA5zUDc9j4BTs8AcJj-21-ykzq6238CnkWc/edit?usp=sharing';
$(document).ready( function() {
Tabletop.init( { key: public_spreadsheet_url,
callback: showInfo,
parseNumbers: true } );
});
function showInfo(data, tabletop) {
var source = $("#cat-template").html();
var template = Handlebars.compile(source);
$.each( tabletop.sheets("food").all(), function(i, food) {
var html = template(food);
$("#content").append(html);
});
}
</script>
<script>
function myFunction() {
var x = document.getElementById("add-info");
if (x.style.display === "none") {
x.style.display = "block";
} else {
x.style.display = "none";
}
}
</script>
</body>
</html>
Are all the entries on your page filled from the given template, meaning they are divs with the class entry? If so, I think your issue is the following: Your entry div has a child div with the id="add-info". And when you click the button, your handler function (myFunction()) tries to get a reference to that div via document.getElementById("add-info"); Now, if you have multiple such entries on a page, you will have multiple divs with id="add-info". But the id attribute of an element must be unique in your whole document. See the description of id or that of getElementById().
So the root cause of your problem is that the same id is used multiple times in the document when it shouldn't be. You get the behavior you're seeing because getElementById() just happens to be returning a reference to the first element it finds on the page, regardless of which button you click. But I believe you're in undefined behavior territory at that point.
One way to solve the problem is to somehow give myFunction() information about which button was clicked, while making each div you'd like to manipulate unique so they can be found easier. For instance, you can use the order of the restaurant on your page as its "index", and use that as the id of the div you'd like to hide/show. And you can also pass this index as an argument when you call your click handler:
...
<button id="btn" class="button-primary" onclick="myFunction('{{index}}')">Hide</button>
<div id="{{index}}">
<!-- The rest of the code here... -->
...
... add the index into your template context, so Handlebars can fill in the {{index}} placeholder:
...
$.each( tabletop.sheets("food").all(), function(i, food) {
food.index = i // Give your context its 'index'
var html = template(food);
$("#content").append(html);
});
...
... and then alter your function slightly to use the given argument instead of always looking for the div with id="add-info":
function myFunction(indexToToggle) {
var x = document.getElementById(indexToToggle);
// rest of the code is same
With this approach, I expect your DOM to end up with divs that have ids that are just numbers ("3", "4", etc.) and your click handler should get called with those as arguments as well.
Also note that your <button> element has id="btn". If you repeat that template on your page, you will have multiple <button>s with the same id. If you start trying to get references to your buttons via id you will have similar issues with them too since the ids won't be unique.

How to dynamically remove elements in javascript?

Is there a way to dynamically remove elements with javascript or jquery. Suppose I have a function createElements() which creates new element and another function removeElement() which is suppose to remove the corresponding element. You will notice that when you run the snippet that when you click on the remove button all the element is gone! How could I implement this code? Isn't there a jquery selector where i could simply use removeElement(this) or somenething like that? Any suggestions are most welcome :) thank you.
function createElements() {
const boom = document.getElementById('boom');
boom.insertAdjacentHTML(
'beforeend', '<div class="newElem"><p >new element created dynamically yay!</p><button onclick="removeElement()">remove</button></div>'
);
}
function removeElement() {
alert('element removed dynamically boOoOoOoOooo!')
$('.newElem').remove();
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="boom">
</div>
<br>
<button onclick="createElements()">Create new element</button>
You can do it like this:
function createElements() {
const boom = document.getElementById('boom');
boom.insertAdjacentHTML(
'beforeend', '<div class="newElem"><p >new element created dynamically yay!</p><button onclick="removeElement(this)">remove</button></div>'
);
}
function removeElement(element) {
alert('element removed dynamically boOoOoOoOooo!')
$(element).parent(".newElem").remove();
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="boom">
</div>
<br>
<button onclick="createElements()">Create new element</button>
You just need to follow one single API. Use either pure JavaScript or jQuery. I would also suggest you to use unobstructive approach. Also, the way you remove the elements is wrong. You are removing everything.
See this way:
$(function() {
$("button#add").click(function() {
$("#boom").after('<div class="newElem"><p >new element created dynamically yay!</p><button class="remove">remove</button></div>');
});
$(document).on("click", ".remove", function() {
alert('element removed dynamically boOoOoOoOooo!')
$(this).closest(".newElem").remove();
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="boom">
</div>
<button id="add">Create new element</button>
To be able to always delete the div that encompasses the remove button, you have to traverse the DOM tree. There are lots of jQuery goodies for this: http://api.jquery.com/category/traversing/
In this particular case, I would do the following:
var elementCounter = 0;
function createElements() {
const boom = document.getElementById('boom');
boom.insertAdjacentHTML(
'beforeend', '<div class="newElem"><p >'+elementCounter+': new element created dynamically yay!</p><button onclick="removeElement(event)">remove</button></div>'
);
elementCounter++;
}
function removeElement(event) {
alert('element removed dynamically boOoOoOoOooo!')
$(event.target).closest('.newElem').remove();
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="boom">
</div>
<br>
<button onclick="createElements()">Create new element</button>
So you pass on the click event to the function as a parameter, and then with event.target you find out which button was clicked. $(event.target).closest(".newElem") will get the first element that matches the selector by testing the element itself and traversing up through its ancestors in the DOM tree.

how to recode my jquery/javascript function to be more generic and not require unique identifiers?

I've created a function that works great but it causes me to have a lot more messy html code where I have to initialize it. I would like to see if I can make it more generic where when an object is clicked, the javascript/jquery grabs the href and executes the rest of the function without the need for a unique ID on each object that's clicked.
code that works currently:
<script type="text/javascript">
function linkPrepend(element){
var divelement = document.getElementById(element);
var href=$(divelement).attr('href');
$.get(href,function (hdisplayed) {
$("#content").empty()
.prepend(hdisplayed);
});
}
</script>
html:
<button id="test1" href="page1.html" onclick="linkPrepend('test1')">testButton1</button>
<button id="test2" href="page2.html" onclick="linkPrepend('test2')">testButton1</button>
<!-- when clicking the button, it fills the div 'content' with the URL's html -->
<div id="content"></div>
I'd like to end up having html that looks something like this:
<button href="page1.html" onclick="linkPrepend()">testButton1</button>
<button href="page2.html" onclick="linkPrepend()">testButton1</button>
<!-- when clicking the button, it fills the div 'content' with the URL's html -->
<div id="content"></div>
If there is even a simpler way of doing it please do tell. Maybe there could be a more generic way where the javascript/jquery is using an event handler and listening for a click request? Then I wouldn't even need a onclick html markup?
I would prefer if we could use pure jquery if possible.
I would suggest setting up the click event in JavaScript (during onload or onready) instead of in your markup. Put a common class on the buttons you want to apply this click event to. For example:
<button class="prepend-btn" href="page2.html">testButton1</button>
<script>
$(document).ready(function() {
//Specify click event handler for every element containing the ".prepend-btn" class
$(".prepend-btn").click(function() {
var href = $(this).attr('href'); //this references the element that was clicked
$.get(href, function (hdisplayed) {
$("#content").empty().prepend(hdisplayed);
});
});
});
</script>
You can pass this instead of an ID.
<button data-href="page2.html" onclick="linkPrepend(this)">testButton1</button>
and then use
function linkPrepend(element) {
var href = $(this).data('href');
$.get(href, function (hdisplayed) {
$("#content").empty().prepend(hdisplayed);
});
}
NOTE: You might have noticed that I changed href to data-href. This is because href is an invalid attribute for button so you should be using the HTML 5 data-* attributes.
But if you are using jQuery you should leave aside inline click handlers and use the jQuery handlers
<button data-href="page2.html">testButton1</button>
$(function () {
$('#someparent button').click(function () {
var href = $(this).data('href');
$.get(href, function (hdisplayed) {
$("#content").empty().prepend(hdisplayed);
});
});
});
$('#someparent button') here you can use CSS selectors to find the right buttons, or you can append an extra class to them.
href is not a valid attribute for the button element. You can instead use the data attribute to store custom properties. Your markup could then look like this
<button data-href="page1.html">Test Button 1</button>
<button data-href="page2.html">Test Button 1</button>
<div id="content">
</div>
From there you can use the Has Attribute selector to get all the buttons that have the data-href attribute. jQuery has a function called .load() that will get content and load it into a target for you. So your script will look like
$('button[data-href]').on('click',function(){
$('#content').load($(this).data('href'));
});
looking over the other responses this kinda combines them.
<button data-href="page2.html" class="show">testButton1</button>
<li data-href="page1.html" class="show"></li>
class gives you ability to put this specific javascript function on whatever you choose.
$(".show").click( function(){
var href = $(this).attr("data-href");
$.get(href,function (hdisplayed) {
$("#content").html( hdisplayed );
});
});
This is easily accomplished with some jQuery:
$("button.prepend").click( function(){
var href = $(this).attr("href");
$.get(href,function (hdisplayed) {
$("#content").html( hdisplayed );
});
});
And small HTML modifications (adding prepend class):
<button href="page1.html" class="prepend">testButton1</button>
<button href="page2.html" class="prepend">testButton2</button>
<div id="content"></div>
HTML code
<button href="page1.html" class="showContent">testButton1</button>
<button href="page2.html"class="showContent">testButton1</button>
<!-- when clicking the button, it fills the div 'content' with the URL's html -->
<div id="content"></div>
JS code
<script type="text/javascript">
$('.showContent').click(function(){
var $this = $(this),
$href = $this.attr('href');
$.get($href,function (hdisplayed) {
$("#content").empty().prepend(hdisplayed);
});
}
});
</script>
Hope it helps.

More then one event in an onclick print event

I have an onclick print event, its working fine but now i have some div's i want to print out, so my question is, how can i make this script working with all id="PrintElement" Or id="PrintElement1" / id="PrintElement2" and so on, so i can add the ID to the div's i want to print out on one paper.
I have this Javascript, thats work with One div called id="PrintElement".
<script type="text/javascript">
//Simple wrapper to pass a jQuery object to your new window
function PrintElement(elem){
Popup($(elem).html());
}
//Creates a new window and populates it with your content
function Popup(data) {
//Create your new window
var w = window.open('', 'Print', 'height=400,width=600');
w.document.write('<html><head><title>Print</title>');
//Include your stylesheet (optional)
w.document.write('<link rel="stylesheet" href="add/css/layout.css" type="text/css" />');
w.document.write('<link rel="stylesheet" href="add/css/main.css" type="text/css" />');
w.document.write('</head><body>');
//Write your content
w.document.write(data);
w.document.write('</body></html>');
w.print();
w.close();
return true;
}
</script>
Then i have a div
<div id="PrintElement">
SOME CODE.....SHORT/LONG
</div>
And to activate the function i have
<a onclick="PrintElement('#PrintElement')">Print</a>
Working fine now i just want it to work with more then one div called id="PrintElement" or if easier i can call the divs ID PrintElement and a number... so it just print out the div's with the ID's
<div id="PrintElement">
SOME CODE.....SHORT/LONG
</div>
<div>
SOME CODE.....SHORT/LONG
</div>
<div id="PrintElement">
SOME CODE.....SHORT/LONG
</div>
<div>
SOME CODE.....SHORT/LONG
<div id="PrintElement">
SOME CODE.....SHORT/LONG
</div>
<div>
SOME CODE.....SHORT/LONG
</div>
</div>
Hope u understand..
You should replace id="PrintElement" with class="PrintElement" in your HTML
And then change your <a onclick="PrintElement('#PrintElement')">Print</a> with <a onclick="PrintElement('.PrintElement')">Print</a>
And then:
function PrintElement(elem){
$(elem).each(function() {
Popup($(this).html());
});
}
This will open a new window for every PrintElement though...
You can collect data with a var and then call Popup at the end of the loop.
EDIT: The code above is using jQuery... so you'll need the library.
EDIT2: If you want to collect data and open only one popup
function PrintElement(elem){
var data = '';
$(elem).each(function() {
data = data + $(this).html();
});
Popup(data);
}
Without jQuery, first move the code that enumerates target IDs to a function, don't embed it in the HTML:
<a onclick="PrintElements()">Print</a>
And in JS:
function PrintElements() {
printElement('#PrintElement1')
printElement('#PrintElement2')
}
There's a better approach, however. You can use classes (<div class="PrintElement">) in your HTML to mark print targets and then pick them up from PrintElements using document.getElementsByClassName.
function PrintElements() {
targets = document.getElementsByClassName('PritnElement')
[].forEach.call(targets, function(x) {
PrintElement(x)
})
}

Replacing widget element with a newly constructed DOM structure

<script>
(function( $ ) {
$.widget( "my.dropbox", {
errorText: function(text) {
$(this.element).next().html(text);
},
_create: function() {
var id = $(this.element).attr("id");
var customDropbox = $(
"<div class='form-group'>"+
"<label for='"+id+"'>"+getLabelFor(id)+"</label>"+
"<select id='"+id+"'></select>"+
"<div class='errors'></div>"+
"</div>"
);
customDropbox.attr("id", id);
$(this.element).replaceWith(customDropbox); // This removes original element from DOM
populateOptions(id);
},
});
}( jQuery ));
$(document).ready(function(){
$("#field1").dropbox(); //blank input field turns into a select with a label, populated options e.t.c..
$("#button1").on("click", function(){
$("#field1").dropbox("errorText", "This is a validation error message"); //throws an error saying dropbox is not initialized
});
});
</script>
<html>
<body>
<input id="field1" />
<button id="button1">Press me</button>
</body>
</html>
So I want a widget with public methods that will replace the original element with all the widget data associated with it. The problem with the above code is that the <select..> element is just a DOM element and if you call .dropbox(..) on it, it will say the widget is not initialized. Is there a way to make the select element into the widget object with the .errorText() method? All widget examples online add stuff around the original element but never replace it. As for the bigger picture, I'm trying to make a generic tool to configure forms dynamically. It's going to be all <input id="..."> in html but then javascript will query a database, get configuration for the field and turn it into a dropbox, checkbox or, say, a date picker with all the labels, validation, and other bells and whistles.
There is more than one issue with your widget code. I'll try to summarize them:
1. Copy the data
You're not copying the data to the newly created customDropbox, so before
this.element.replaceWith(customDropbox);
you should copy the data:
customDropbox.data(this.element.data());
Now the widget will remember that it was initialized.
2. this.element is gone
After
this.element.replaceWith(customDropbox);
you should update this.element so that it points to the newly created customDropbox:
this.element = customDropbox;
3. errorText message takes wrong element
Since the widgets element (this.element) is now pointing to the <div class='form-group'></div> element, the errorText function must be slightly modified to:
this.element.find(".errors").html(text);
4. id should be unique
Now, both the wrapper <div> and the <select> have the same id, which is not allowed in HTML so remove the one on the <select> tag. Luckily, <label> can work without the for attribute, just write it like this:
<label>labelForId <select></select></label>
Then to get the <select>-element, use this.element.find("select") in the widget.
Side note
`this.element` is already a jQuery element, so no need for the additional `$()` wrapping.
See this jsFiddle
function show(){
$("#field1").input({....});
}
function hide(){
$("#field1").input("hide");
}
<button onclick="show()">show</button>
<button onclick="hide()">hide</button>
i think to replace the origin element which initial dropbox() is not a good solution,
because this will force you to rely on the implemention details of jQuery ui factory,
it is easy to make a mistake or introduce bugs, sometimes harder for other people to understand your code
if jquery ui factory change the implemention in the future, you have to modify all your code to make it work
(sorry for my limit understand of jquery ui)
i think we can put the <input/> into a container and initial dropbox() on the container which inturn
replace <input/> with <select> datepicker ..etc.. we can build modules easily by doing so:
<form>
<div class="dropbox"><label for="someID">aaaaaa</label><input id="someID"/></div>
<div class="datepicker"></div>
<div class="othermodule"></div>
</form>
js:
$(".dropbox").dropbox(); // init dropbox you defined
$(".datepicker").datepicker(); // ...
$(".othermodule").othermodule(); // ...
$(".dropbox").dropbox("errorText", "error"); // invoke it smoothly
here is a simple demo: http://jsfiddle.net/m4A3D/
#Wouter Huysentruit's answer provides a list of good suggestion for me
<form>
<div class="dropbox">
<label for="someID">aaaaaa</label>
<input id="someID"/>
</div>
<div class="datepicker"></div>
<div class="othermodule"></div>
</form>
<button id="button1">Press me</button>
<script>
(function ($){
$.widget("my.dropbox", {
_create: function () {
var $input = this.element.find("input");
var sID = $input.attr("id");
var $select = $("<select>");
$select.attr("id", sID);
$input.replaceWith($select);
this.element.append("<div class='errors'></div>");
}, // end _create()
errorText: function (text) {
this.element.find(".errors").text(text);
} // end errorText()
});
}(jQuery));
$(".dropbox").dropbox();
$("#button1").click(function () {
$(".dropbox").dropbox("errorText", "this is error");
});
</script>

Categories

Resources