Applying Events Handler to Child Elements (Event Propogation in jQuery) - asp.net

Edit : Problem wasn't related Event Propagation, if you want to know how to stop propagation in jQuery, then use event.stopPropagation();
When user moves his/her mouse over <span> element my jQuery code appends an <img>into this <span> element and when he moves out his mouse off <span> than the element appended is removed. It helps people to edit the field when clicking on the appended <img> element.
The reason I used append() method to add <img> into <span> is because I want to keep <img> element visible when user moves his mouse over to appended <img> element (<img> is becoming <span>'s child element) But it didn't happen and when user moves his mouse over it <img> is being deleted. I am thinking it is because event propagation but I couldn't find how to activate it in jQuery as we do with addEventListener in Firefox based browsers.
Here is the code :
JQuery Code :
$(document).ready(function() {
$('.EditEnabled').bind("mouseover", ShowEditFields);
$(".EditEnabled").bind("mouseout", HideEditFields);
});
function ShowEditFields(event) {
$(event.target).append(" <img id='editImg' src='images/edit.png' style='margin-bottom:-3px'/>");
}
function HideEditFields(event) {
$(event.target).children("#editImg").remove();
}
Simple HTML :
<span id="something" class="EditEnabled">Something Here</span>
Can you explain my how to solve it.
Thank you.

You want to use the jQuery mouseenter and mouseleave events, not mousover and mouseout. The reason is that mouseout will fire when you move the mouse over the img.
Thankfully, jQuery combines this into a hover method:
$(document).ready(function() {
$('.EditEnabled').hover(ShowEditFields, HideEditFields);
});
However I agree with the other answer that you should use CSS to do this vs. manipulating the DOM. I would just use the :hover pseudo selector, and then add special support for IE6.
CSS
span.EditEnabled img { display: none }
span.EditEnabled:hover img,
span.EditEnabled.hover img { display: block }
Make sure you have the img in the span in your HTML to begin with, and that is all you need for most browsers and IE7+
To support IE6 add:
<!--[if lte IE 6]>
<script type="text/javascript">
$(function(){
$(".EditEnabled").hover(
function(){ $(this).addClass('hover') },
function(){ $(this).removeClass('hover')}
);
});
</script>
<![endif]-->

Firstly, I would avoid as much DOM manipulation as you can. The ideal scenario is to construct your markup like this:
<span class="editEnabled">Some data<img ...></span>
with CSS:
span.editEnabled img { display: none; }
span.editEnabled img.visible { display: inline; }
and Javascript:
$(function() {
$("span.editEnabled").hover(function() {
$(this).children("img").addClass("visible");
}, function() {
$(this).children("img").removeClass("visible");
});
});
That should pretty much do it.
I would avoid the jQuery effects as making things visible will make them block level elements rather than inline like you want.

I've found another answer actually, the way I am looking for. It might not be a best practice but at least I've found out how to solve that.
$(document).ready(function() {
// $('.EditEnabled').bind("mouseenter", ShowEditFields);
// $(".EditEnabled").bind("mouseleave", HideEditFields);
$(".EditEnabled").hover(ShowEditFields, HideEditFields);
});
function ShowEditFields(event) {
var target = $(event.target);
if (target.is(":has(#editImg)") == false)
target.append(" <img id='editImg' src='images/edit.png' style='margin-bottom:-3px;display:inline'></img>");
}
function HideEditFields(event) {
// event.stopPropagation();
// if ($(event.relatedTarget).is("#editImg") == false)
$(event.target).children("#editImg").remove();
}

Related

SASS smart alternate link underline on hover

and if a link is underlined, i want it to get rid of the underline on hover. If a link has no underline, i want it to get one on hover.
Is there a smart way to do this with SASS rather than hard coding it for every link?
As others have stated, to do this within CSS or SASS this is something that requires a default style for links and a class or data attribute that must be applied to alternative links.
The type of auto-smart styling is possible with javascript though if that's an acceptable alternative. I made a quick jQuery Fiddle that would work by checking all links for the text-decoration style. This has performance drawbacks due to scanning the DOM for all links every page load. It also breaks the law of keeping styling with the CSS realm so it's up to you if it's worth it.
var links = $('a');
links.each(function (i) {
var $this = $(this);
// if this has underline
if ($this.css('text-decoration') == 'underline') {
$this.hover(
function() {
$this.css('text-decoration', 'none');
}, function() {
$this.css('text-decoration', 'underline');
});
} else {
$this.hover(
function() {
$this.css('text-decoration', 'underline');
}, function() {
$this.css('text-decoration', 'none');
});
};
});
https://jsfiddle.net/ym8s6Lwh/

Hide a whole div with CSS with part of it is empty

Is there a way to hide a whole div if part of it is empty? For example if "dd" is empty as shown below can I hide the whole class "test" so the keyword Restrictions does not show either. I tried .test dd:empty { display: none; } but this does not work. thanks!
<div class="test"><dt>Restrictions:</dt>
<dd></dd></div>
I don't think there's any easy way to do what you're talking about with just CSS. Better to test it server-side if you can. But if you can't here's some JS that will do the job.
<script type="text/javascript">
// handles multiple dt/dd pairs per div and hides them each conditionally
function hideIfEmpty() {
// get all the elements with class test
var els = document.getElementsByTagName('dl');
// for every 'test' div we find, go through and hide the appropriate elements
Array.prototype.map.call(els, function(el) {
var children = el.childNodes;
var ddEmpty = false;
for(var i = children.length - 1; i >= 0; i--) {
if(children[i].tagName === 'DD' && !children[i].innerHTML.trim()) {
ddEmpty = true;
} else if(children[i].tagName === 'DT') {
if(ddEmpty) {
children[i].style.display = 'none';
}
// reset the flag
ddEmpty = false;
}
}
});
}
window.addEventListener('load', hideIfEmpty);
</script>
<div class="test">
<div style="clear: both;"></div>
<dl>
<dt>Restrictions:</dt>
<dd></dd>
<dt>Other Restrictions:</dt>
<dd>Since I have content, I won't be hidden.</dd>
</dl>
</div>
Just a fair warning: the code uses some functions that may not exist in older IE, such as Array.prototype.map, String.prototype.trim, and addEventListener. There are polyfills available for these and you could also write your own pretty easily (or just do it with a for loop instead).
CSS alone can't do that. Either, you need a javascript to retrieve empty elements and hide their parents, or your CMS applies special CSS classes if there's no content.
Put as an answer as requested by #Barett.
You could update your CSS to be
.test{
display: none;
color: transparent;
}
This would make the text transparent too, but display:none should hide it anyway.
To make the div with the id test ONLY show when the dd tag is EMPTY, and you can use jQuery, try the following JavaScript along with the CSS:
if($("dd").html().length ==0)
{show();
}
Note: this solution requires jQuery, which is a JavaScript library.

Hovering over an image changes HTML background

Basically:
div:hover
{
body{ background-image:(bg.png); }
}
This is logical code, I know it does not work, but its the best how I can show you my problem.
Well what your trying to accomplish cannot be achieved that way using Css only, You can do it using jquery like this
$("#someDiv").hover(function(){
$("body").css("background-image", "url('image_url')")
});
In css ,You can not do this as "body" is parent element to "div" and it should come next to the element hovered to use the for format like
firstelement:hover second_element {/*styles*/}
you can use jquery to achieve it
$("div").hover(function(){
$("body").css("background", "url('url_of_image_here')")
});
or javascript
elem = document.getElementById("ID");
elem.addEventListener("mouseout", function(){
document.getElementsByTagName("body")[0].style.backgroundImage="url()";
});

how to style a selected button/link with css or javascript?

I would like to style my selected button.
I would like to display a light-blue border around the image of my selected button to show which page the user is on. (or just use the same hover image as the selected button image when the button is pushed.)
I didn't have success with the css link selectors :visited, :focus, or :selected.
Does this require a javascript solution?
thanks for any pointers!
i usually just a extra class name called selected
<div class="button selected">Button 1</div>
<div class="button">Button 2</div>
.selected {
border: 1px solid #0000ff;
}
It depends on how you display your page (using ajax or refresh on every click). If you are using javascript to load the page content than you just put an extra classname using javascript when the button is clicked.
you should use :active pseudo class in css to achieve what you want.
jQuery Solution with your CSS
You would probably want to check first if it is selected, that way this solution works with things like Twitter Bootstrap, where you can make any element act like a button:
$(function () {
$('div.button').click(function(){
if ($(this).hasClass('selected') {
$(this).removeClass('selected');
//Insert logic if you want a type of optional click/off click code
}
else
{
$(this).addClass('selected');
//Insert event handling logic
}
})
});
You will, in fact, need to use javascript. I did this in a project a while back, by iterating through the links in the navbar, and setting a class called "selected" on the one the user is currently visiting.
If you use jQuery, you can accomplish it like this:
$(function() {
$('#navbar li').each(function() {
if ($(this).children('a').attr('href') == window.location.pathname)
{
$(this).addClass('active');
}
});
})
The CSS Pseudo-selector :active won't still be active after a pagereload.

IE select issue with hover

A friend and myself are trying to workaround IE (7/8). We have built a canonical example here:
http://www.mathgladiator.com/share/ie-select-bug-hover-css-menus.htm
Using a CSS menu, we would like to have selects in them. However, in IE, the menu goes away when you interact with the select box. We believe this has to do with a bug in how selects affect events.
Is there a workaround? At least with pure CSS or DOM hacks?
I do not think there is a pure CSS way around this. This is due to a very common bug to the way IE handles events on select elements.
You can however work around it with Javascript:
<script type="text/javascript">
$(document).ready(function () {
$('.nav_element a').mouseover(function() {
$('.submenu').hide();
$(this).parent().find('.submenu').show();
});
$('.submenu').mouseover(function() {
$(this).show();
});
$('.submenu').mouseout(function (e) {
// Do not close if going over to a select element
if (e.target.tagName.toLowerCase() == 'select') return;
$(this).hide();
});
});
</script>
The code above uses jQuery.
Here is a way to improver select behavior in IE7/8, but it does not fix the issue
Change DOCTYPE
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
Add script
<script>
function ddlOut(e) {
setTimeout(function() { e.className = e.className.replace(' over', ''); }, 1000)
}
</script>
Add css
#nav .over div.submenu
{
display: block;
}
#nav .nav_element{
behavior: expression(
this.onmouseover = new Function("this.className += ' over'"),
this.onmouseout = new Function("ddlOut(this)"),
this.style.behavior = null
);
}
It will work better at least but of course not perfect.
My advice is to change select control to html equivalent. I use OboutDropDown that has a nice view. There are many implementations that can suite you needs.
First you need to expand the :hover surface underneath your menu.
So in your css add width:310px;height:220px to #nav .nav_element a.
(also add a class or an id on the second div styled with top:220px)
Now you just need to simulate a mousedown triggered when you click on the select which will halt when the selection between the options is done - you can probably do the last part if you check for the onfocus state of the select which will stop the mousedown.

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