How to make Javascript function work only one time ?
if (window.location.hash) {
$(document).ready(function () {
var id = window.location.hash;
$(id).trigger('click');
});
$('li').click(function () {
$(this).prependTo($(this).parent());
});
}
I need auto-click on that li element which link user comes to website. web.com/#2 (list order - 2 1 3 4 5) , web.com/#4 (list order - 4 1 2 3). but i want than user stay in website with hash url list elements stay in their places then user click for example on 3 list element he must stay and his place so list order (4 1 2 3). I just need change list order by url hash on load page.
I solved it
if (window.location.hash) {
$('li').one('click',function () {
if (!window.run){
$(this).prependTo($(this).parent());
window.run = true;
}
});
$(document).ready(function () {
var id = window.location.hash;
$(id).trigger('click');
});
}
In your particular case the simplest solution is to use .one(), which unbinds the handler after running it the first time:
$('li').one('click',function () { ... }
Another approach is to have the function redefine itself to a no-op after it runs. This can be useful in some cases when there isn't a convenient event handler to unbind:
var oneTimeFunction = function() {
console.log("This will only happen once.");
oneTimeFunction = function() {};
}
I have a requirement to change the text on hover of multiple menu items at once but I cannot use CSS and nor can I give each individual item its own CSS class. What I would like to do is when the mouse hovers anywhere over the .menu-wrapper the Javascript replaces each of the <li> item texts with the relevant replacement text.
I have a script which works perfectly for a single item:
<div class="menu-wrapper">
<ul>
<li>WORD1</li>
</ul>
</div>
Javascript:
var originalText = $('.menu-wrapper > ul > li').text();
$('.menu-wrapper').hover(function () {
var $p = $(this).find('li');
$p.fadeOut(300, function () {
$(this).text('replacement word 1').fadeIn(300);
});
}, function () {
// set original text
$(this).find('li').fadeOut(300, function () {
$(this).text(originalText).fadeIn(300);
});
});
But obviously if you add multiple <li> items it breaks because it is only storing a single .text() variable and concatenates all the entries after the first mouseout event.
I tried using a switch statement to look for the value of the .text() and change the text value accordingly but it didn't work (my Javascript is weak...).
I'd appreciate any help with this. I only have four items to replace the text of so repeating any script as necessary is not a problem. Normally I would give each one it's own class identity and use what I already have but unfortunately I can't.
Please don't suggest using CSS as I already know how to do that but for this I need to use Javascript.
I could not find this question elsewhere.
Thanks!
Main issue is first line:
var originalText = $('.menu-wrapper > ul > li').text();
This will get all text from all elements in the collection:
What you could do is store that text on each element using jQuery data() by looping over the elements and dealing with instances:
$('.menu-wrapper > ul > li').each(function(){
$(this).data('original', $(this).text());
});
Then in mouseout part of hover read the previously stored text using data() again
$(this).find('li').fadeOut(300, function () {
var originalText = $(this).data('original');
$(this).text(originalText).fadeIn(300);
});
Several options for the new text:
Put it in markup as data attribute
<li data-alt_text="alternate word">
Then within mousenter callback of hover:
$p.fadeOut(300, function () {
$(this).text($(this).data('alt_text')).fadeIn(300);
});
Or put in array and use first loop to add the array data to element
var words=['W1','W2','W3'];
// first argument of "each" is "index"
$('.menu-wrapper > ul > li').each(function(index){
$(this).data(
{
'alt_text': words[index],
'original', $(this).text()
}
);
});
You can make use of javascripts ability to assign any property to an object (element) to store the original text instead of storing it in a single variable (or use jquery data functionality to do the same)
$('.menu-wrapper li').hover(function () {
$(this).fadeOut(300, function () {
this.originalText = $(this).text();
$(this).text('replacement word 1').fadeIn(300);
});
}, function () {
// set original text
$(this).fadeOut(300, function () {
$(this).text(this.originalText).fadeIn(300);
});
});
fiddle
For this to work, instead of binding to the .menu-wrapper div directly, you can use .menu-wrapper li to bind to the individual li elements inside the div. Afterwards the orignal text can be stored before changing it. The same can be done beforehand, storing all values, the advantage of this way is that you always store the latest value, in case the text is dynamically altered after startup.
To couple the replacement texts to the li elements, without altering the html safest would be to couple the replacement to the text. Easiest is an indexed based solution:
var replacements = ['replacement Word1', 'for word2' , 'third time\'s a charm'];
$('.menu-wrapper li').hover(function () {
var $this= $(this);
$this.fadeOut(300, function () {
$this.data('originalText', $this.text()).
text(replacements[$this.index()]).fadeIn(300);
});
}, function () {
// set original text
$(this).fadeOut(300, function () {
$(this).text($(this).data('originalText')).fadeIn(300);
});
});
fiddle
For completeness sake, this would be an alternative while using the li text (provided the text can be used as a property):
var replacements ={
WORD1 : 'replacement Word1',
WORD2 : 'for word2',
WORD3: 'third time\'s a charm'
};
$('.menu-wrapper li').hover(function () {
var $this= $(this);
$this.fadeOut(300, function () {
$this.data('originalText', $this.text()).
text(replacements[$this.text()]).fadeIn(300);
});
}, function () {
// set original text
$(this).fadeOut(300, function () {
$(this).text($(this).data('originalText')).fadeIn(300);
});
});
fiddle
Here's a short and simple solution to your problem:
var originalText;
$('.menu-wrapper').hover(function () {
var $p = $(this).find('li');
$p.fadeOut(300, function () {
this.originalText = $(this).text(); // STORES VALUE BEFORE REPLACEMENT
$(this).text('replacement word 1').fadeIn(300);
});
}, function () {
$(this).find('li').fadeOut(300, function () {
$(this).text(this.originalText).fadeIn(300);
});
});
Just store the value of that element in originalText before replacing it.
We can use two arrays to store Original text and New text. And then use $.each to loop through each of the lis and use their index to replace the text.
HTML :
<div class="menu-wrapper">
<ul>
<li>WORD1</li>
<li>WORD2</li>
<li>WORD3</li>
</ul>
</div>
jQuery :
var originaltext = ['Word1','Word2','Word3'];
var newText = ['New text1','New text2','New text3'];
$('.menu-wrapper').hover(function () {
$('.menu-wrapper li').each(function(i){
$this = $(this);
$this.html(newText[i])
});
}, function(){
$('.menu-wrapper li').each(function(i){
$this = $(this);
$this.html(originaltext[i])
});
});
jsfiddle
Since all of the other answers here use jQuery, I'll add one done with vanilla js.
To do this, we're going to need to use a javascript closure. This is used so that on completion of the fade-out, we have (a) the element just faded and (b) which is far more important, an index into the originalStrings array. (B) is the more important here, because the target element is something the animate code already has - we could easily pass the original element to the callback function. However, we really need the index or the string that corresponds to each element. The closure gives a means to do so.
The following code will fade-out all/any matching elements and then perform a fade-in after changing the text.
Using the equations found here: Math: Ease In, ease Out a displacement using Hermite curve with time constraint we can then set about making some code that will perform a smooth fade/move/scale pitch/volume slide etc, etc. I did this an ended up a few functions that facilitate simple animations. I've included minified versions of them below, for an all-in-one complete solution that relies on no other resources.
<!DOCTYPE html>
<html>
<head>
<script>
"use strict";
window.addEventListener('load', onDocLoaded, false);
function onDocLoaded()
{
document.getElementById('goBtn').addEventListener('click', onButtonClick, false);
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// animation stuff
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
function cubicHermite(a,b,d,e,c){var g=a*a,f=g*a;return(2*f-3*g+1)*b+(f-2*g+a)*e+(-2*f+3*g)*d+(f-g)*c}
function interp(a,b,d,e,c){var g,f;f=e/(a/2+b+d/2);g=f*a/2;f*=b;return c<=a?cubicHermite(c/a,0,g,0,f/b*a):c<=a+b?g+f*(c-a)/b:cubicHermite((c-a-b)/d,g+f,e,f/b*d,0)}
function linear(a){return a}
function cubic(a){return interp(0.35,0.3,0.35,1,a)}
function doAnimStep(a,b,d,e,c){a<=b?(setTimeout(function(){doAnimStep(a,b,d,e,c)},d),e(a/b),a++):void 0!=c&&null!=c&&c()}
function doAnim3(totalMs, stepCallbackFunc, doneCallbackFunc)
{
var stepDelay = 1000 / 60.0; // set anim to 60 fps
var numSteps = (totalMs / stepDelay)>>0;
setTimeout( doAnim3TimeoutCallback, stepDelay );
function doAnim3TimeoutCallback()
{
doAnimStep(0, numSteps, stepDelay, stepCallbackFunc, doneCallbackFunc);
};
}
function animFadeOut(elem, callback){ doAnim3(500,function(raw){elem.style.opacity=1-cubic(raw)},callback); }
function animFadeIn(elem, callback) { doAnim3(500,function(raw){elem.style.opacity=cubic(raw)},callback); }
////////////////////////////////////////////////////////////////////////////////////////////////////////////////
var replacementStrings = [ "replacement 1", "I'm next", "mee too", "fourth item" ];
function onButtonClick(evt)
{
var originalStrings = [];
var targetLiElems = document.querySelectorAll('.menu-wrapper > ul > li');
for (var i=0,n=targetLiElems.length;i<n;i++)
{
var curElem = targetLiElems[i];
originalStrings.push(curElem.innerText);
animFadeOut(curElem, createFunc(i) );
}
function createFunc(i)
{
return function(){ var curElem = targetLiElems[i]; curElem.innerText = replacementStrings[i]; animFadeIn(curElem); };
}
}
</script>
<style>
</style>
</head>
<body>
<button id='goBtn'>Change the text</button>
<div class="menu-wrapper">
<ul>
<li>WORD1</li>
<li>WORD2</li>
<li>WORD3</li>
<li>WORD4</li>
</ul>
</div>
</body>
</html>
I'm using Template.rendered to setup a dropdown replacement like so:
Template.productEdit.rendered = function() {
if( ! this.rendered) {
$('.ui.dropdown').dropdown();
this.rendered = true;
}
};
But how do I re-run this when the DOM mutates? Helpers return new values for the select options, but I don't know where to re-execute my .dropdown()
I think you don't want this to run before the whole DOM has rendered, or else the event handler will run on EVERY element being inserted:
var rendered = false;
Template.productEdit.rendered = function() {rendered: true};
To avoid rerunning this on elements which are already dropdowns, you could give new ones a class which you remove when you make them into dropdowns
<div class="ui dropdown not-dropdownified"></div>
You could add an event listener for DOMSubtreeModified, which will do something only after the page has rendered:
Template.productEdit.events({
"DOMSubtreeModified": function() {
if (rendered) {
var newDropdowns = $('.ui.dropdown.not-dropdownified');
newDropdowns.removeClass("not-dropdownified");
newDropdowns.dropdown();
}
}
});
This should reduce the number of operations done when the event is triggered, and could stop the callstack from being exhausted
Here's my tentative answer, it works but I'm still hoping Meteor has some sort of template mutation callback instead of this more cumbersome approach:
Template.productEdit.rendered = function() {
if( ! this.rendered) {
$('.ui.dropdown').dropdown();
var mutationOptions = {
childList: true,
subtree: true
}
var mutationObserver = new MutationObserver(function(mutations, observer){
observer.disconnect(); // otherwise subsequent DOM changes will recursively trigger this callback
var selectChanged = false;
mutations.map(function(mu) {
var mutationTargetName = Object.prototype.toString.call(mu.target).match(/^\[object\s(.*)\]$/)[1];
if(mutationTargetName === 'HTMLSelectElement') {
console.log('Select Changed');
selectChanged = true;
}
});
if(selectChanged) {
console.log('Re-init Select');
$('.ui.dropdown').dropdown('restore defaults');
$('.ui.dropdown').dropdown('refresh');
$('.ui.dropdown').dropdown('setup select');
}
mutationObserver.observe(document, mutationOptions); // Start observing again
});
mutationObserver.observe(document, mutationOptions);
this.rendered = true;
}
};
This approach uses MutationObserver with some syntax help I found here
Taking ad educated guess, and assuming you are using the Semantic UI Dropdown plugin, there are four callbacks you can define:
onChange(value, text, $choice): Is called after a dropdown item is selected. receives the name and value of selection and the active menu element
onNoResults(searchValue): Is called after a dropdown is searched with no matching values
onShow: Is called after a dropdown is shown.
onHide: Is called after a dropdown is hidden.
To use them, give the dropdown() function a parameter:
$(".ui.dropdown").dropdown({
onChange: function(value, text, $choice) {alert("You chose " + text + " with the value " + value);},
onNoResults: function(searchValue) {alert("Your search for " + searchValue + " returned no results");}
onShow: function() {alert("Dropdown shown");},
onHide: function() {alert("Dropdown hidden");}
});
I suggest you read the documentation of all plugins you use.
I have the following function. To make a long story short, I have 4 divs that I want to apply an init class to. The init class essentially shows the 4 divs.
It works as it should, however it shows all 4 divs at the same time, which is not what I want. I want to show 1 div, then the next, then the next, etc.
Where am I going wrong?
$('.campaign-item').waypoint({
handler: function() {
var $this = $(this);
$this.each(function(i) {
setTimeout(function() {
$this.addClass('init');
}, i * 500 );
});
},
offset: '60%'
});
$('.campaign-item').each(function (i) {
var $this = $(this);
$this.waypoint({
handler: function() {
setTimeout(function() {
$this.addClass('init');
}, i * 500 );
},
offset: '60%'
});
});
You need to add the class to each individual element, not to all of them.
var $this = $(this);
$this.each(function(i,v){
setTimeout(function(){
$(v).addClass('init');
}, i * 500 );
});
I think your problem is that a jQuery object contains a collection of the objects that match your selector. "$(this)" is that collection. The "each" function gives you access to the individual elements in that collection with the returned second parameter ("function(index, element)"). In your code you are trying to add your "init" class to every member of the collection because "$this" IS the entire collection. You need to add the class to the second parameter returned in each iteration of your each function.
I'm using this flip plugin, see the code in this fiddle. The goal is to flip one box at a time, e.g. the second box clicked should revertFlip() the previous one. During the animation I don't want the other boxes to be clickable. I noted that the removeClass() is not working.
<div class='flippable'>I'm unflipped 1</div>
...
<div class='flippable'>I'm unflipped 9</div>
$('.flippable:not(.reverted)').live('click',function()
{
var $this = $(this);
var $prevFlip = $('.reverted');
var $allBoxes = $('.flippable');
$this.flip(
{
direction: 'lr',
color: '#82BD2E',
content: 'now flipped',
onBefore: function()
{
$prevFlip.revertFlip();
$prevFlip.removeClass('reverted');
},
onAnimation: function ()
{
$allBoxes.preventDefault();
},
onEnd: function()
{
$this.addClass('reverted');
}
})
return false;
});
I'll appreciate a lot your advise and suggestions.
Edit:
Error Console Output: $allBoxes.preventDefault is not a function
I believe this has something to do with revertFlip() calling onBefore and onEnd. This is causing some weirdness with addClass and removeClass. Check out my modified example: http://jsfiddle.net/andrewwhitaker/7cysr/.
You'll see if you open up FireBug that onBefore and onEnd are called multiple times, with I think is having the following effect (I haven't exactly worked out what's going on):
The call to onEnd for the normal "flip" sets reverted class for the desired element.
The call to onEnd for the "revert flip" action sets the same element as above again when onEnd is called.
Here's a workaround. I've taken out using onBegin and simplified onEnd since I'm not exactly sure what's going on with the revertFlip() call:
$(function() {
var handlerEnabled = true;
$('.flippable:not(.reverted)').live('click', function() {
if (handlerEnabled) {
var $this = $(this);
var $prevFlip = $('.reverted');
var $allBoxes = $('.flippable');
handlerEnabled = false;
$prevFlip.revertFlip();
$prevFlip.removeClass("reverted");
$this.addClass("reverted");
$this.flip({
direction: 'lr',
color: '#82BD2E',
content: 'now flipped',
onEnd: function() {
handlerEnabled = true;
}
});
}
return false;
});
})
I'm using a boolean flag to enable and disable the event listener. Try out this example: http://jsfiddle.net/andrewwhitaker/bX9pb/. It should work as you described in your OP (only flipping one over at a time).
Your original code ($allBoxes.preventDefault()) is invalid, because $allBoxes is a collection of elements. preventDefault is a function on the jQuery event object.
Can you try this script
var $prevFlip;
$('.flippable:not(.reverted)').live('click',function() {
var $this = $(this);
var $allBoxes = $('.flippable');
$this.flip( {
direction: 'lr',
color: '#82BD2E',
content: 'now flipped',
onBefore: function() {
if($prevFlip){
$prevFlip.revertFlip();
$prevFlip.removeClass('reverted');
}
},
onAnimation: function () {
//$allBoxes.preventDefault();
//This is not a valid line
},
onEnd: function() {
$this.addClass('reverted');
$prevFlip = $this;
}
});
return false;
});
This reverts only one previous item. This is not a complete solution. I think there are more problems to this. I'll post any further updates if I found them.
I think #Andrew got the answer you are looking for.
You can filter $this out of $allBoxes by using the not() method.
$allBoxes.not($this).revertFlip();