combining a method to hide or show content - javascript

I was wondering how I can combine a hide function and show function into 1 toggle Function that either fades in content or fades it out, im guessing this argument would update the fade method:
This is my current effort of JS using jQuery from my object but is totally wrong:
toggleAlertOverlay: function (state) {
var instance = this;
if (state === hide) {
instance.selector.fadeOut();
}
elseif(state === show) {
instance.selector.fadeIn();
}
},
toggleAlertOverlay(hide);

Try using .fadeToggle()
The .fadeToggle() method animates the opacity of the matched elements. When called on a visible element, the element's display style property is set to none once the opacity reaches 0, so the element no longer affects the layout of the page.
$(<element>).fadeToggle();
Where <element> is a valid selector ....

var toggleState = 'none';
toggleAllertOverlay: function()
{
if(toggleState == 'none')
{
$('#element').fadeIn();
toggleState == 'showing';
}
else
{
$('#element').fadeOut();
toggleState == 'none';
}
}
is just a concept based on what you have. Note the variable outside of the function. Its outside so it doesn't get destroyed upon function complete. But aside from that, theres various other methods you can try if this doesn't suit you. Up to and including jQuery toggle()

Related

Get child div of existing div using anchors next element without ID or class using JQuery

As you can see below $(nextDiv + ' > div').eq(i).fadeIn('slow'); does not work as it seems to be malformed. nextDiv is on inspection the div below the anchor, how do I achieve getting the two divs that sit inside it?
HTML:
Sub Click
<div>
<div>I want this to fade in on the click</div>
<div>Followed by this etc.</div>
</div>
Javascript:
function subClick(myAnchor)
{
var nextDiv = $(myAnchor).next();
function showDiv(i) {
if (i > 2) return;
setTimeout(function () {
$(nextDiv + ' > div').eq(i).fadeIn('slow');
showDiv(++i);
}, 50);
}
showDiv(0);
}
You are trying to concatenate a string with jQuery, that won't provide a valid selector. The concatenation would provide something like "[object Object] > div" which doesn't select any elements in your code.
Instead, get the div children using children() method on the jQuery nextDiv object.
nextDiv.children('div').eq(i).fadeIn('slow');
If there are only two divs then you can reduce the code using delay() method.
function subClick(myAnchor) {
var nextDivs = $(myAnchor).next().children();
// if you want to do the animation after the first then
// use the below code, where second animation initializing within
// the first animation success callback, which also provides a 50ms
// delay for second animation(avoid .delay(50) if you dont nedd that delay)
// nextDivs.eq(0).fadeIn('slow', function() {
// nextDivs.eq(1).delay(50).fadeIn('slow');
// });
// in case you just want to provide a 50ms delay
// between animation then use, your code does this
nextDivs.eq(0).fadeIn('slow');
nextDivs.eq(1).delay(50).fadeIn('slow');
}
var nextDiv = $(myAnchor).next(); then nextDiv is an object not a selector. If you want to access its div children use this:
nextDiv.children('div').eq(i).fadeIn('slow');

jquery wrap, append, prepend to parent div

I am trying to detect when a certain div element has a height of 0 in order to display a div element with a message.
function checkads()
{
if ($('#container').height() == 0)
{
$('.wp_bannerize').wrap($('<div id="notice">ENABLE ADS</div>'));
};
}
$(document).ready(checkads);
The above works fine, however, is there anyway to make the script wrap the parent div that is 1 or 2 levels above the child div without having to define the class name of the parent manually "wp_bannerize"
You could try something like this:
function checkads() {
var $container = $('#container');
if ($container.height() == 0) {
$container.parent().wrap($('<div id="notice">ENABLE ADS</div>'));
// OR $container.parent().parent().wrap($('<div id="notice">ENABLE ADS</div>'));
}
}
Or change your checkads() function to:
function checkads($current) {
if ($current.height() == 0) {
$current.parent().wrap($('<div id="notice">ENABLE ADS</div>'));
}
}
And call it like:
checkads($('#container');
checkads($('#container2');
//etc...
You can use $('#container').parent().parent() to find the parent of the parent, for example. You can also use $('#container').closest('div') to search through the parent list for the closest div (or whatever). You don't need to know the class name (although you can also use that with closest!)

Checking if Element hasClass then prepend and Element

What I am trying to achieve here is when a user clicks an element it becomes hidden, once this happens I want to prepend inside the containing element another Element to make all these items visible again.
var checkIfleft = $('#left .module'),checkIfright = $('#right .module');
if(checkIfleft.hasClass('hidden')) {
$('#left').prepend('<span class="resetLeft">Reset Left</span>');
} else if(checkIfright.hasClass('hidden')) {
right.prepend('<span class="resetRight">Reset Right</span>');
}
I tried multiple ways, and honestly I believe .length ==1 would be my best bet, because I only want one element to be prepended. I believe the above JS I have will prepend a new element each time a new item is hidden if it worked.
Other Try:
var checkIfleft = $('#left .module').hasClass('hidden'),
checkIfright = $('#right .module').hasClass('hidden');
if(checkIfleft.length== 1) {
$('#left').prepend('<span class="resetLeft">Reset Left</span>');
} else if(checkIfright.length== 1) {
right.prepend('<span class="resetRight">Reset Right</span>');
}
else if(checkIfleft.length==0){
$('.resetLeft').remove()
} else if (checkIfright.length==0){
$('.resetRight').remove()
}
Basically if one element inside the container is hidden I want a reset button to appear, if not remove that reset button...
hasClass() only works on the first item in the collection so it isn't doing what you want. It won't tell you if any item has that class.
You can do something like this instead where you count how many hidden items there are and if there are 1 or more and there isn't already a reset button, then you add the reset button. If there are no hidden items and there is a reset button, you remove it:
function checkResetButtons() {
var resetLeft = $('#left .resetLeft').length === 0;
var resetRight = $('#left .resetRight').length === 0;
var leftHidden = $('#left .module .hidden').length !== 0;
var rightHidden = $('#right .module .hidden').length !== 0;
if (leftHidden && !resetLeft) {
// make sure a button is added if needed and not already present
$('#left').prepend('<span class="resetLeft">Reset Left</span>');
} else if (!leftHidden) {
// make sure button is removed if no hidden items
// if no button exists, this just does nothing
$('#left .resetLeft').remove();
}
if (rightHidden && !resetRight) {
$('#right').prepend('<span class="resetRight">Reset Right</span>');
} else if (!rightHidden) {
$('#right .resetRight').remove();
}
}
// event handlers for the reset buttons
// uses delegated event handling so it will work even though the reset buttons
// are deleted and recreated
$("#left").on("click", ".resetLeft", function() {
$("#left .hidden").removeClass("hidden");
$("#left .resetLeft").remove();
});
$("#right").on("click", ".resetRight", function() {
$("#right .hidden").removeClass("hidden");
$("#right .resetRight").remove();
});
FYI, if we could change the HTML to use more common classes, the separate code for left and right could be combined into one piece of common code.
Add the reset button when hiding the .module, if it's not already there :
$('#left .module').on('click', function() {
$(this).addClass('hidden');
var parent = $(this).closest('#left');
if ( ! parent.find('.resetLeft') ) {
var res = $('<span />', {'class': 'resetLeft', text : 'Reset Left'});
parent.append(res);
res.one('click', function() {
$(this).closest('#left').find('.module').show();
$(this).remove();
});
}
});
repeat for right side !
I've recently experimented with using CSS to do some of this stuff and I feel that it works quite well if you're not trying to animate it. Here is a jsfiddle where I can hide a module and show the reset button in one go by adding/removing a 'hideLeft' or 'hideRight' class to the common parent of the two modules.
It works by hiding both reset button divs at first. Then it uses .hideLeft #left { display:none;} and .hideLeft #right .resetLeft { display: block; } to hide the left module and display the reset button when .hideLeft has been added to whichever element both elements descend from. I was inspired by modernizr a while back and thought it was a neat alternative way to do things. Let me know what you think, if you find it helpful, and if you have any questions :)

hide one div when another is showing in jQuery?

I am trying to hide a div when another one is visible.
I have div 1 and div 2.
If div 2 is showing then div 1 should hide and if div 2 is not showing then div 1 should be visible/unhide.
The function would need to be function/document ready upon page load.
I've tried this but I'm not having any luck, can someone please show me how I can do this.
<script>
window.onLoad(function () {
if ($('.div2').is(":visible")) {
$(".div1").fadeOut(fast);
} else if ($('.div2').is(":hidden")) {
$('.div1').fadeIn(fast);
}
});
</script>
Add a class of hidden to each div, then toggle between that class using jQuery. By the way, window.onload is not a function, it expects a string like window.onload = function() {}. Also, put fast in quotations. I don't know if that's required, but that's how jQuery says to do it.
<div class="div1"></div>
<div class="div2 hidden"></div>
.hidden { display: none }
$(document).ready(function() {
if($(".div1").hasClass("hidden")) {
$(".div2").fadeIn("fast");
}
else if($(".div2").hasClass("hidden")) {
$(".div1").fadeIn("fast");
}
});
You should pass a string to the .fadeIn() and .fadeOut() methods.
Instead of .fadeIn(fast) it'll be .fadeIn("fast"). Same for .fadeOut().
And in general since you're already using jQuery it's better to wrap your code like this:
$(function () {
// Code goes here
});
It looks like you're using jquery selectors (a javascript library). If you're going to use jquery make sure the library is loaded properly by including it in the document header (google makes this easy by hosting it for you <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>)
With jQuery loaded you can do it like this
$(document).ready(function(){
if ($('.div1').is(":visible")) {
$('div2').hide();
}
else if ($('.div2').is(":visible")) {
$('div1').hide();
}
});
WORKING EXAMPLE: http://jsfiddle.net/HVDHC/ - just change display:none from div 2 to div 1 and click 'run' to see it alternate.
You can use setTimeout or setInterval to track if these divs exists
$(function() {
var interval = window.setInterval(function() {
if($('#div2').hasClass('showing')) {
$('#div1').fadeOut('fast');
}
if($('#div2').hasClass('hidden')) {
$('#div1').fadeIn('fast');
}
}, 100);
// when some time u don't want to track it
// window.clearInterval(interval)
})
for better performance
var div1 = $('#div1')
, div2 = $('#div2')
var interval ....
// same as pre code

Can someone explain the following javascript code?

In addition to the explanation, what does the $ mean in javascript? Here is the code:
var ZebraTable = {
bgcolor: '',
classname: '',
stripe: function(el) {
if (!$(el)) return;
var rows = $(el).getElementsByTagName('tr');
for (var i=1,len=rows.length;i<len;i++) {
if (i % 2 == 0) rows[i].className = 'alt';
Event.add(rows[i],'mouseover',function() {
ZebraTable.mouseover(this); });
Event.add(rows[i],'mouseout',function() { ZebraTable.mouseout(this); });
}
},
mouseover: function(row) {
this.bgcolor = row.style.backgroundColor;
this.classname = row.className;
addClassName(row,'over');
},
mouseout: function(row) {
removeClassName(row,'over');
addClassName(row,this.classname);
row.style.backgroundColor = this.bgcolor;
}
}
window.onload = function() {
ZebraTable.stripe('mytable');
}
Here is a link to where I got the code and you can view a demo on the page. It does not appear to be using any framework. I was actually going through a JQuery tutorial that took this code and used JQuery on it to do the table striping. Here is the link:
http://v3.thewatchmakerproject.com/journal/309/stripe-your-tables-the-oo-way
Can someone explain the following
javascript code?
//Shorthand for document.getElementById
function $(id) {
return document.getElementById(id);
}
var ZebraTable = {
bgcolor: '',
classname: '',
stripe: function(el) {
//if the el cannot be found, return
if (!$(el)) return;
//get all the <tr> elements of the table
var rows = $(el).getElementsByTagName('tr');
//for each <tr> element
for (var i=1,len=rows.length;i<len;i++) {
//for every second row, set the className of the <tr> element to 'alt'
if (i % 2 == 0) rows[i].className = 'alt';
//add a mouseOver event to change the row className when rolling over the <tr> element
Event.add(rows[i],'mouseover',function() {
ZebraTable.mouseover(this);
});
//add a mouseOut event to revert the row className when rolling out of the <tr> element
Event.add(rows[i],'mouseout',function() {
ZebraTable.mouseout(this);
});
}
},
//the <tr> mouse over function
mouseover: function(row) {
//save the row's old background color in the ZebraTable.bgcolor variable
this.bgcolor = row.style.backgroundColor;
//save the row's className in the ZebraTable.classname variable
this.classname = row.className;
//add the 'over' class to the className property
//addClassName is some other function that handles this
addClassName(row,'over');
},
mouseout: function(row) {
//remove the 'over' class form the className of the row
removeClassName(row,'over');
//add the previous className that was stored in the ZebraTable.classname variable
addClassName(row,this.classname);
//set the background color back to the value that was stored in the ZebraTable.bgcolor variable
row.style.backgroundColor = this.bgcolor;
}
}
window.onload = function() {
//once the page is loaded, "stripe" the "mytable" element
ZebraTable.stripe('mytable');
}
The $ doesn't mean anything in Javascript, but it's a valid function name and several libraries use it as their all-encompassing function, for example Prototype and jQuery
From the example you linked to:
function $() {
var elements = new Array();
for (var i=0;i<arguments.length;i++) {
var element = arguments[i];
if (typeof element == 'string') element = document.getElementById(element);
if (arguments.length == 1) return element;
elements.push(element);
}
return elements;
}
The $ function is searching for elements by their id attribute.
This function loops through the rows in a table and does two things.
1) sets up alternating row style. if (i % 2 == 0) rows[i].className = 'alt' means every other row has its classname set to alt.
2) Attaches a mouseover and mouseout event to the row so the row changes background color when the user mouses over it.
the $ is a function set up by various javascript frameworks ( such as jquery) that simply calls document.getElementById
The code basically sets alternating table rows to have a different CSS class, and adds a mouseover and mouseout event change to a third css class, highlighting the row under the mouse.
I'm not sure if jQuery, prototype or maybe another third party JS library is referenced, but the dollar sign is used by jQuery as a selector. In this case, the user is testing to see if the object is null.
$ is the so-called "dollar function", used in a number of JavaScript frameworks to find an element and/or "wrap" it so that it can be used with framework functions and classes. I don't recognize the other functions used, so I can't tell you exactly which framework this is using, but my first guess would be Prototype or Dojo. (It certainly isn't jQuery.)
The code creates a ZebraTable "object" in Javascript, which stripes a table row by row in Javascript.
It has a couple of member functions of note:
stripe(el) - you pass in an element el, which is assumed to be a table. It gets all <tr> tags within the table (getElementsByTagName), then loops through them, assigning the class name "alt" to alternating rows. It also adds event handlers for mouse over and mouse out.
mouseover(row) - The "mouse over" event handler for a row, which stores the old class and background colour for the row, then assigns it the class name "over"
mouseout(row) - The reverse of mouseover, restores the old class name and background colour.
The $ is a function which returns an element given either the elements name or the element itself. It returns null if its parameters are invalid (non-existent element, for example)
I believe the framework being used is Prototype, so you can check out their docs for more info
Have a look at the bottom of the article that you have got the code from, you'll see that they say you'll also need prototype's $ function. From article
In your CSS you’ll need to specify a
default style for table rows, plus
tr.alt and tr.over classes. Here’s a
simple demo, which also includes the
other functions you’ll need (an Event
registration object and Prototype’s $
function).

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