I have 3 divs:
(blue) containing div with position: relative
(red) div with overflow: hidden, floated left
(green) div with position: absolute that I want positioned relatively to the first div.
see jsfiddle.
I want the green div hidden outside the red div, so making the overflow: hidden work without positioning it, because I want the green one positioned relative to the blue one.
I found some similar questions, but none that really fit this same case.
You are on the right track, but you need to make the red div have relative positioning.
Right now, your green div is being positioned absolutely relative to the blue one, but as long as that is happening, it is bound by the overflow rules of the blue one, not the red one.
When you use absolute positioning, the positioned element is bound by the overflow of the nearest parent element with relative positioning, ultimately the window if no others exist.
.two{
background-color: red;
overflow: hidden;
float: left;
position:relative;
}
JSFiddle
I believe this is impossible using only css. You could make it look like what your talking about using javascript or jquery fairly easy, but I wasn't sure if you wanted an answer in that form.
Related
I'm asking this for learning purposes; there aren't any negative aspects on this behaviour, but I just wonder if this could have any negative consequences in the future.
So I have a container div: content_wrap, which has two other div's: side_bar and main_content. The container div is 980px width, and is used to center its contents using margin-left and margin-right.
It's doing this correctly, however, when I was debugging the page (in Firefox), I noticed that the browser renders the div as being 0x0px and renders the parent div off-screen. However, it does position the child divs correctly. See this JSFiddle for an example: http://jsfiddle.net/7fsXp/7/
I Googled this and most of the answers have something to do with floats and are solved by using clear:both, but I don't use any floats. I did notice that if I change the main_content div from position:absolute; to position:relative;, the content_wrap is displayed correctly. Or I can fix it by setting a height for content_wrap.
I don't actually need to be able to see the content_wrap, so there isn't really a problem, as it is doing its job in means of centering the child divs. I just wondered if it would be a bad practice to leave it like this? Is it a bad thing, or does it matter?
Try adding other elements to this HTML and enjoy the horror :D
There are actually many things in your code, that I wouldn't do. First of all, when an element is with position: absolute or position: fixed its layout is "ignored" by other elements or in other words cannot "push" any element and that is why your container is having 0 height. It's like they are ethereal (best explanation ever, I know).
You should check this article on positioning -- http://css-tricks.com/absolute-relative-fixed-positioining-how-do-they-differ/
The fact that they are in the place you expect them to be is that there are actually no other elements in the HTML and the absolute element is positioned relatively to the body and so is the fixed one (but that's what elements with position: fixed always do). Looks what happens when I add some other content to the parent div -- http://jsfiddle.net/7fsXp/13/
So long story short - you shouldn't form your layout with absolute or fixed elements if you can do it without them.
position: fixed and position: absolute take the elements out of the flow, so using either of these positions on all child divs will collapse the parent div entirely.
If you have content below a collapsed div, it will flow up and over/under that content like this.
You don't need to position the main_content div absolutely, but you'll need to change a few things to top align the sidebar and main_content.
DEMO
Since sidebar is fixed, it's using the document, not the container div as a reference for top, while main_content would use the body (unless you add position: relative to the container). Getting rid of the body's default padding/margin will fix the small alignment difference.
body {
padding: 0;
margin: 0;
}
#main_content {
//remove position: absolute;
margin-top:70px; //top: 70px won't work unless you specify position
}
It depends on what you are willing to do, but because the default position for div is position: static; changing the position: relative; will avoid the collapse of parent div.
I have a site with absolute positioned elements on it, for example the top Navigation of the site:
#topNav
{
position: absolute;
top: 100px;
left: 50%;
height: 40px;
width: 1000px;
margin-left: -500px;
}
Now I created a sticky footer like on the following site:
http://ryanfait.com/resources/footer-stick-to-bottom-of-page/
Now, the problem is that the footer will "overlap" the topNav,
because the topNav is positioned absolute, which means it's "outside of the normal float of elements". The relative position will not "notice" that there is the topNav before.
Before I start creating additional "pusher divs" for each absolute positioned element I would better ask if there are better practices than "pusher divs" or should I even not use position absolute on my elements?
EDIT:
JsFiddle here: http://jsfiddle.net/dkxUX/15/
When you scale down your browserwindow you'll find #footer overlapping all elements before it.
You could just apply a 140px top margin/padding to the body or other container element which would make the topNav's height and offset accounted for.
Better yet, don't set position to absolute in this case - it appears to me that all you're doing is horizontally centering a 1000px wide div.
/*top-margin of 100px + center the element*/
#topNav {width:1000px; height:40px; margin:100px auto 0;}
Update: I see your jsfiddle now. You could account for all absolutely positioned elements when setting the margin/padding as suggested in the first paragraph You are using absolutely positioned elements when normal document flow could be relied on.
a little bit too late to give an answer but it may help someone in the future, I came up with that problem not too long ago so here was my shot at it, using jquery since I couldn't came up with a CSS solution that wasn't removing the DOCTYPE tag (which isn't something you should do, anyways).
So here it is.
$("#CONTAINERDIV").prepend("<div id='relativefix' style='position:relative;margin-top:"+($("#YOUR_ABSOLUTE_DIV").offset().top+$("#YOUR_ABSOLUTE_DIV").outerHeight()+30)+"px'></div>");
$(window).resize(function(){
$("#relativefix").css("margin-top",($("#YOUR_ABSOLUTE_DIV").offset().top+$("#YOUR_ABSOLUTE_DIV").outerHeight()+30)+"px");
});
So yeah, that's all there is to it, you just dynamically add another div at the start of the container hard-placed under the absolute div, that will force all subsequent relative divs to me placed after it, it is like a clear fix for someone who ran out of ideas.
Basically, I want to center text, ignoring any floating sibling elements.
At first, I thought this wouldn't be a problem, as I was under the impression that a floating element did not take from the width of any sibling elements.
Example (I want the red text to be at the center of the blue box, despite the green text)
How is this best achieved?
You can't. If it were centered within the parent box, then the float would overlap the content at some point, which would be defeating the point of the float. There are two approaches you can use here. If you know the width of the float, you can apply an equal negative right margin. Otherwise, you can absolutely position the element like this.
Here's a link to a working fiddle: http://jsfiddle.net/cD657/3/
(in your example, you opened a <span>, and closed it with </div>)
I made it a div and gave it margin: 0px auto; and a width. -seemed to do the trick
You can keep as you have it but just adding padding on the opposite side with the same pixel value as the width of the floating element.
.parent{
text-align: center;
}
.centered.element{
padding-left: [width of floating element]px;
}
.floating.element{
float: left;
}
To find the width easily just use Developer Tools in any modern browser to Inspect the element.
See fiddle here: http://jsfiddle.net/cD657/369/
Note: This may not work if the centered element has an assigned background color.
This is a CSS issue that doesn't make sense to me..
Right now I have something like this:
.container {
height: 500px;
width: 500px;
position: relative;
padding: 10px;
}
.child {
top:0px;
left:0px;
position:absolute;
width: 100px;
height: 100px;
}
The child right now disregards padding of parent. This seems counter-intuitive to me. Am I missing a quick fix (I can't add padding/margin to child)? Did I mess up the DOCTYPE?
Thanks!
Matt Mueller
Since you have specified position absolute for the child element this behavior is the correct one. The child will be positioned absolutely with the left and top value.
In the absolute positioning model, a
box is explicitly offset with respect
to its containing block. It is removed
from the normal flow entirely (it has
no impact on later siblings). An
absolutely positioned box establishes
a new containing block for normal flow
children and absolutely (but not
fixed) positioned descendants.
However, the contents of an absolutely
positioned element do not flow around
any other boxes. They may obscure the
contents of another box (or be
obscured themselves), depending on the
stack levels of the overlapping boxes.
Visual Formatting model - Absolute positioning
<style type="text/css">
.a {
border: 1px solid #000;
position: relative;
}
.b {
background: #F93;
position: absolute;
top: 50px;
left: 50px;
}
</style>
<div class="a">
<div class="b">test</div>
</div>
a's height doesn't autoresize with it's content(beause b has flow), but how to resolve this problem, use css possible, not javascript.
If you are expecting to see your a-div resize, then I think you've misunderstood something. When you set an element to be absolute, you're taking it out of the "rendering flow", which means it won't interfere with any other elements on the page.
In the absolute positioning model, a box is explicitly offset with respect to its containing block. It is removed from the normal flow entirely (it has no impact on later siblings). An absolutely positioned box establishes a new containing block for normal flow children and absolutely (but not fixed) positioned descendants. However, the contents of an absolutely positioned element do not flow around any other boxes. They may obscure the contents of another box (or be obscured themselves), depending on the stack levels of the overlapping boxes.
You see the following documentation: Absolute positioning
When you have a Div with position:relative, you can control any absolute element inside. In fact, absolute Div is out of the flow of the normal document as Greg mentioned above. As I see you set left and top for b and then if you set width of a to 60px like this. Your <div class="b"> is outside the parent box. This is how absolute elements work.
Try "float: left;" in both classes. Didn't test, however. In wich browser are you testing?
if div b is positioned absolute it's not considered 'inside a' anymore, because it's not rendered inside of it.
so div a will not resize as div b gets larger or smalller...
By setting position: absolute you're taking the div outside the normal document flow, which is why the container won't resize to contain it.
Did you want to set margin-top: 50px; margin-left: 50px; instead?