Grow height of parent div that contains floating nested divs - html

I can’t seem to auto-grow my parent div’s height based on its floating child divs. All the children are floating, to take up space horizontally, and then wrapping to the next line. There can be a changing number of floating children, and the parent has to auto-size its height. (The parent div serves as a background for all the floating divs). There is also a second div below the parent div that needs to be pushed down, so that it is below the floating divs.
It’s of major importance that the solution works in IE.

If the parent container only has floating children, it will have no height. Adding the following CSS to the parent container should help:
.parent {
overflow:hidden;
width: 100%;
}
Read this article for more: http://www.quirksmode.org/css/clearing.html.

You could insert a div that clears the floaters after the last child.
HTML:
<div style="clear: both"></div> <!-- This goes after the last floated element - no floating elements are allowed on either side of this. -->
fiddle: http://jsfiddle.net/Rc5J8/

You need to clear floated elements the height of their parents will collapse.
The current accepted answer is correct, however it's usually a better idea to clear floats by applying the clearfix hack or overflow: hidden to a wrapping parent element so that margins continue to functions as expected, and to get rid of an empty HTML element.
The overflow-method:
CSS:
.wrap { overflow: hidden }
.box { float: left; }
Markup:
<div class="wrap">
<div class="box">
Content
</div>
<div class="box">
Content
</div>
</div>
The clearfix-method, as linked above:
CSS:
.cf:before,
.cf:after {
content: " ";
display: table;
}
.cf:after { clear: both; }
.cf { *zoom: 1; }
.box { float: left; }
Markup:
<div class="wrap cf">
<div class="box">
Content
</div>
<div class="box">
Content
</div>
</div>

You should use the clearfix technique on the containing div
http://www.webtoolkit.info/css-clearfix.html
That removes the need to add extra markup.

Adding the overflow css property on the parent element will fix the issue (no need for an empty & ugly div element to clear the float) :
.parentelement {
overflow:auto;
display: block;
width: 100%;
}
I added the display and width properties because some browsers will need theses properties to be defined.

You need to apply clearfix to the parent as floats are removed from the flow of the document an don't automatically add any height to the parent's contents. Clearfix instructs teh parent to extend to a height tall enough to clear its last floated child. This method is well established and works across browsers.

Related

Why doesn't the height of a container element increase if it contains floated elements?

I would like to ask how height and float work. I have an outer div and an inner div that has content in it. Its height may vary depending on the content of the inner div but it seems that my inner div will overflow its outside div. What would be the proper way to do it?
<html>
<body>
<div style="margin:0 auto;width: 960px; min-height: 100px; background-color:orange">
<div style="width:500px; height:200px; background-color:black; float:right"></div>
</div>
</body>
</html>
The floated elements do not add to the height of the container element, and hence if you don't clear them, container height won't increase...
I'll show you visually:
More Explanation:
<div>
<div style="float: left;"></div>
<div style="width: 15px;"></div> <!-- This will shift
besides the top div. Why? Because of the top div
is floated left, making the
rest of the space blank -->
<div style="clear: both;"></div>
<!-- Now in order to prevent the next div from floating beside the top ones,
we use `clear: both;`. This is like a wall, so now none of the div's
will be floated after this point. The container height will now also include the
height of these floated divs -->
<div></div>
</div>
You can also add overflow: hidden; on container elements, but I would suggest you use clear: both; instead.
Also if you might like to self-clear an element you can use
.self_clear:after {
content: "";
clear: both;
display: table;
}
How Does CSS Float Work?
What is float exactly and what does it do?
The float property is misunderstood by most beginners. Well, what exactly does float do? Initially, the float property was introduced to flow text around images, which are floated left or right. Here's another explanation by #Madara Uchicha. So, is it wrong to use the float property for placing boxes side by side? The answer is no; there is no problem if you use the float property in order to set boxes side by side.
Floating an inline or block level element will make the element behave like an inline-block element.Demo
If you float an element left or right, the width of the element will be limited to the content it holds, unless width is defined explicitly ...
You cannot float an element center. This is the biggest issue I've always seen with beginners, using float: center;, which is not a valid value for the float property. float is generally used to float/move content to the very left or to the very right. There are only four valid values for float property i.e left, right, none (default) and inherit.
Parent element collapses, when it contains floated child elements, in order to prevent this, we use clear: both; property, to clear the floated elements on both the sides, which will prevent the collapsing of the parent element. For more information, you can refer my another answer here.
(Important) Think of it where we have a stack of various elements. When we use float: left; or float: right; the element moves above the stack by one. Hence the elements in the normal document flow will hide behind the floated elements because it is on stack level above the normal floated elements. (Please don't relate this to z-index as that is completely different.)
Taking a case as an example to explain how CSS floats work, assuming we need a simple 2 column layout with a header, footer, and 2 columns, so here is what the blueprint looks like...
In the above example, we will be floating only the red boxes, either you can float both to the left, or you can float on to left, and another to right as well, depends on the layout, if it's 3 columns, you may float 2 columns to left where another one to the right so depends, though in this example, we have a simplified 2 column layout so will float one to left and the other to the right.
Markup and styles for creating the layout explained further down...
<div class="main_wrap">
<header>Header</header>
<div class="wrapper clear">
<div class="floated_left">
This<br />
is<br />
just<br />
a<br />
left<br />
floated<br />
column<br />
</div>
<div class="floated_right">
This<br />
is<br />
just<br />
a<br />
right<br />
floated<br />
column<br />
</div>
</div>
<footer>Footer</footer>
</div>
* {
-moz-box-sizing: border-box; /* Just for demo purpose */
-webkkit-box-sizing: border-box; /* Just for demo purpose */
box-sizing: border-box; /* Just for demo purpose */
margin: 0;
padding: 0;
}
.main_wrap {
margin: 20px;
border: 3px solid black;
width: 520px;
}
header, footer {
height: 50px;
border: 3px solid silver;
text-align: center;
line-height: 50px;
}
.wrapper {
border: 3px solid green;
}
.floated_left {
float: left;
width: 200px;
border: 3px solid red;
}
.floated_right {
float: right;
width: 300px;
border: 3px solid red;
}
.clear:after {
clear: both;
content: "";
display: table;
}
Let's go step by step with the layout and see how float works..
First of all, we use the main wrapper element, you can just assume that it's your viewport, then we use header and assign a height of 50px so nothing fancy there. It's just a normal non floated block level element which will take up 100% horizontal space unless it's floated or we assign inline-block to it.
The first valid value for float is left so in our example, we use float: left; for .floated_left, so we intend to float a block to the left of our container element.
Column floated to the left
And yes, if you see, the parent element, which is .wrapper is collapsed, the one you see with a green border didn't expand, but it should right? Will come back to that in a while, for now, we have got a column floated to left.
Coming to the second column, lets it float this one to the right
Another column floated to the right
Here, we have a 300px wide column which we float to the right, which will sit beside the first column as it's floated to the left, and since it's floated to the left, it created empty gutter to the right, and since there was ample of space on the right, our right floated element sat perfectly beside the left one.
Still, the parent element is collapsed, well, let's fix that now. There are many ways to prevent the parent element from getting collapsed.
Add an empty block level element and use clear: both; before the parent element ends, which holds floated elements, now this one is a cheap solution to clear your floating elements which will do the job for you but, I would recommend not to use this.
Add, <div style="clear: both;"></div> before the .wrapper div ends, like
<div class="wrapper clear">
<!-- Floated columns -->
<div style="clear: both;"></div>
</div>
Demo
Well, that fixes very well, no collapsed parent anymore, but it adds unnecessary markup to the DOM, so some suggest, to use overflow: hidden; on the parent element holding floated child elements which work as intended.
Use overflow: hidden; on .wrapper
.wrapper {
border: 3px solid green;
overflow: hidden;
}
Demo
That saves us an element every time we need to clear float but as I tested various cases with this, it failed in one particular one, which uses box-shadow on the child elements.
Demo (Can't see the shadow on all 4 sides, overflow: hidden; causes this issue)
So what now? Save an element, no overflow: hidden; so go for a clear fix hack, use the below snippet in your CSS, and just as you use overflow: hidden; for the parent element, call the class below on the parent element to self-clear.
.clear:after {
clear: both;
content: "";
display: table;
}
<div class="wrapper clear">
<!-- Floated Elements -->
</div>
Demo
Here, shadow works as intended, also, it self-clears the parent element which prevents to collapse.
And lastly, we use footer after we clear the floated elements.
Demo
When is float: none; used anyways, as it is the default, so any use to declare float: none;?
Well, it depends, if you are going for a responsive design, you will use this value a lot of times, when you want your floated elements to render one below another at a certain resolution. For that float: none; property plays an important role there.
Few real-world examples of how float is useful.
The first example we already saw is to create one or more than one column layouts.
Using img floated inside p which will enable our content to flow around.
Demo (Without floating img)
Demo 2 (img floated to the left)
Using float for creating horizontal menu - Demo
Float second element as well, or use `margin`
Last but not the least, I want to explain this particular case where you float only single element to the left but you do not float the other, so what happens?
Suppose if we remove float: right; from our .floated_right class, the div will be rendered from extreme left as it isn't floated.
Demo
So in this case, either you can float the to the left as well
OR
You can use margin-left which will be equal to the size of the left floated column i.e 200px wide.
You need to add overflow:auto to your parent div for it to encompass the inner floated div:
<div style="margin:0 auto;width: 960px; min-height: 100px; background-color:orange;overflow:auto">
<div style="width:500px; height:200px; background-color:black; float:right">
</div>
</div>
jsFiddle example
You are encountering the float bug (though I'm not sure if it's technically a bug due to how many browsers exhibit this behaviour). Here is what is happening:
Under normal circumstances, assuming that no explicit height has been set, a block level element such as a div will set its height based on its content. The bottom of the parent div will extend beyond the last element. Unfortunately, floating an element stops the parent from taking the floated element into account when determining its height. This means that if your last element is floated, it will not "stretch" the parent in the same way a normal element would.
Clearing
There are two common ways to fix this. The first is to add a "clearing" element; that is, another element below the floated one that will force the parent to stretch. So add the following html as the last child:
<div style="clear:both"></div>
It shouldn't be visible, and by using clear:both, you make sure that it won't sit next to the floated element, but after it.
Overflow:
The second method, which is preferred by most people (I think) is to change the CSS of the parent element so that the overflow is anything but "visible". So setting the overflow to "hidden" will force the parent to stretch beyond the bottom of the floated child. This is only true if you haven't set a height on the parent, of course.
Like I said, the second method is preferred as it doesn't require you to go and add semantically meaningless elements to your markup, but there are times when you need the overflow to be visible, in which case adding a clearing element is more than acceptable.
Its because of the float of the div. Add overflow: hidden on the outside element.
<div style="overflow:hidden; margin:0 auto;width: 960px; min-height: 100px; background-color:orange;">
<div style="width:500px; height:200px; background-color:black; float:right">
</div>
</div>
Demo
You confuse how browsers renders the elements when there are floating elements. If one block element is floating (your inner div in your case), other block elements will ignore it because browser removes floating elements from the normal flow of the web page. Then, because the floated div has been removed from the normal flow, the outside div is filled in, like the inner div isn't there. However, inline elements (images, links, text, blackquotes) will respect the boundaries of the floating element. If you introduce text in the outside div, the text will place arround de inner div.
In other words, block elements (headers, paragraphs, divs, etc) ignore floating elements and fill in, and inline elements (images, links, text, etc) respect boundaries of floating elements.
An fiddle example here
<body>
<div style="float:right; background-color:blue;width:200px;min-height:400px;margin-right:20px">
floating element
</div>
<h1 style="background-color:red;"> this is a big header</h1>
<p style="background-color:green"> this is a parragraph with text and a big image. The text places arrounds the floating element. Because of the image is wider than space between paragrah and floating element places down the floating element. Try to make wider the viewport and see what happens :D
<img src="http://2.bp.blogspot.com/_nKxzQGcCLtQ/TBYPAJ6xM4I/AAAAAAAAAC8/lG6XemOXosU/s1600/css.png">
</p>
Try this one
.parent_div{
display: flex;
}
you can use overflow property to the container div if you don't have any div to show over the container eg:
<div class="cointainer">
<div class="one">Content One</div>
<div class="two">Content Two</div>
</div>
Here is the following css:
.container{
width:100%;/* As per your requirment */
height:auto;
float:left;
overflow:hidden;
}
.one{
width:200px;/* As per your requirment */
height:auto;
float:left;
}
.two{
width:200px;/* As per your requirment */
height:auto;
float:left;
}
-----------------------OR------------------------------
<div class="cointainer">
<div class="one">Content One</div>
<div class="two">Content Two</div>
<div class="clearfix"></div>
</div>
Here is the following css:
.container{
width:100%;/* As per your requirment */
height:auto;
float:left;
overflow:hidden;
}
.one{
width:200px;/* As per your requirment */
height:auto;
float:left;
}
.two{
width:200px;/* As per your requirment */
height:auto;
float:left;
}
.clearfix:before,
.clearfix:after{
display: table;
content: " ";
}
.clearfix:after{
clear: both;
}

Div is not as tall as the total height of its floated children

OK, I'm really having problems understanding the behavior of the float property.
The page is 750 px wide. In order to keep it positioned in the center of the screen, I used this code:
<div align="center">
<div align="left" style="width:750px; border-style:double;">
stuff
</div>
</div>
The elements within the main 750 px wide container are other containers that have the following styles:
div.infoCont //these containers usualy have two more containers within- for an image and text
{
width: 740px;
position: relative;
left: 2px;
border-style: double; //for debugging
float: left;
}
div.textContNI //text only
{
width: 730px;
float: left;
clear: right;
border-style: double; //for debugging
}
The small containers behave normally (they should be, because they are positioned and as big as the way I want to). But the height of the main container is A LOT less that the total height of the smaller containers... 0 px. It ignores the height of ALL the smaller containers.
This can be "fixed" by adding text right before the closing tag of the main container. I can also manipulate the height with <br> tags and no text: the height becomes as big as the total height of the borders. Another way to "fix" the problem is to add float:left; in the style, but that positions the container on the left side of the window and I can't have that.
I'm missing something and I don't know what it is.
Why does the main container ignore the total height of the containers within it and how can I take care of this bug?
Containing floated elements
This is the correct behavior of floated elements. It's not a bug.
By default, a floated element doesn't occupy space within its parent. The same happens with elements given absolute position. The parent has two children, but they're both floated, so nothing occupies space in the parent. As a result the parent has a height of zero, unless it contains some other non-floated content.
There are three common ways to make a parent contain its floated children, so that it's at least as tall as its children.
1. Fixed height
Give the parent a fixed height that's at least as tall as the height of the floated child. Technically, the floated element still does not occupy space within the parent, but the parent is tall enough to make it appear as if it does.
.parent { height: 30px; }
.child { height: 30px; float: left; }
2. clear div
Add a trailing div with clear:both inside the parent. This forces the parent to contain the floated children. The parent automatically increases in height as needed. By default, an empty div has a height of zero in all browsers, so no additional styling is required for the trailing div.
.clear { clear: both; }
...
<div class="parent">
<!-- Floated children go here -->
...
<!-- Trailing clear div goes here -->
<div class="clear"></div>
</div>
3. clearfix
Add a clearfix rule to the CSS stylesheet, and add the class clearfix to the parent. The end result is the same as adding a clear div, but it doesn't require adding additional HTML elements. Like adding a clear div, this forces the parent to contain the floated children. The parent automatically increases in height as needed.
/* The traditional version of clearfix, a good one to start with. */
.clearfix:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}
.clearfix {display: inline-block;}
* html .clearfix {height: 1%;}
.clearfix {display: block;}
...
<div class="parent clearfix">
<!-- Floated children go here -->
...
</div>

Floating divs in the absolute div are not expanding the parent. Clearfix doesn't seem to work

I have this issue: two floating divs inside an absolute-positioned parent div.
CSS:
.wrapper {
position: absolute;
left: 0;
top: 0;
overflow: hidden; /* doesn't do anything! */
}
.left {
float: left;
}
.right {
float: right;
}
.clear {
clear: both;
}
HTML:
<div class="wrapper">
<div class="left">some text here</div>
<div class="right">some text here too</div>
<div class="clear"></div>
</div>
In Firefox, if the wrapper doesn't have position:absolute, everything works, as intended. As soon as I make it absolute, the wrapper shrinks and the content in floating divs overlap the rest of the document. Also, if I set the wrapper's width to 100% it overlaps the vertical scrollbar.
What am I missing?
Since you're using the overflow: hidden clearfix, the div.clear is completely unnecessary. But since you're also positioning your wrapper absolutely the overflow: hidden clearfix is also unnecessary as position: absolute will also clearfix (at least in Chrome and FF).
http://jsfiddle.net/j6jkk/
Floating an element takes it out of the document flow. That means it will not have an impact on its parent's dimensions, and absolutely positioned elements are 0 x 0 by default. Clearing the floated element's next sibling is only going to expand the width of the parent container if you actually have content in that element, have its width set in its style, or one of its other siblings still in the document flow has width greater than the parent's initial width.
See this article from the Mozilla Developer Network, although this is true of CSS in general, not just Firefox:
float - MDN
Regarding the width: 100% issue, if the offset parent of the wrapper is the document, this may be how Firefox responds to the positioning style. You might be able to alleviate that by placing the absolutely positioned element in an empty div with position set to relative.
Try adding this:
.wrapper{
display: inline-block;
}

Vertically centering multiple div's in its parent div

I have a set of elements inside a parent element. The parent element's height can change (it will be changed by some jQuery files). Here is how the layout looks:
<div class = "parent">
<div class="child1">
</div>
<div class="child2">
</div>
</div>
I want the child elements to end up aligned at the middle of the parent div, but i can't figure out how to write the css to do so. I have tried writing things like:
.child1 {
...
vertical-align: middle;
}
Which doesn't work. I have also tried:
.parent {
display:table;
}
.child1 {
display:table-cell;
vertical-align:middle;
}
This also doesn't work. Any ideas how to do this?
You can create a wrapper for the elements you wish to center inside a container that gets centered instead like so:
HTML
<div class ="parent">
<div class="centerme">
<div class="child1">
....
</div>
<div class="child2">
....
</div>
</div>
</div>
Then you can simply do this:
CSS
.block:before {
content: '';
display: inline-block;
height: 100%;
vertical-align: middle;
margin-right: -0.25em; /* Adjusts for spacing */
}
Demo. Method found over at CSS-tricks.
Check this link : http://www.jakpsatweb.cz/css/css-vertical-center-solution.html
this will bring your child div's top to 50% of the container. just add margin-top: -(x)px; where (x) is half of your child div's height.
You have forgotten to apply the same styling on child2 as on child1, like so:
.child1, .child2 {
display:table-cell;
vertical-align:middle;
}
Here is a jsfiddle: http://jsfiddle.net/D853q/1/
This is slightly more complicated than your standard "how do I vertically align a single div inside a parent container."
If you have a multiple number (which can change) of child elements that need to be aligned vertically or if your parent container's height changes, then you will need to use Javsacript/JQuery to set the position as there is no "standard" way to apply a middle vertical alignment to multiple child elements inside a parent container utilizing just CSS.
EDIT: I've been proven wrong, you can apparently with using :before pseudo-element, but it won't work in IE7 unless you hack around it.
I've implemented this in a fiddle: http://jsfiddle.net/rJJah/20/
Key parts
Each Child element has a position:relative. This is important because certain child elements may have variable height, and this eliminates the need to calculate the top position separately for each.
Everytime you change the height of the parent container, you will need to rerun the height calculations and setting the top offset to each child.

When should overflow:hidden be used for a <div>?

Suppose I have this HTML structure:
<div class="a">
<div class="floated-left">...</div>
<div class="floated-left">...</div>
</div>
I have noticed that if I don't set overflow:hidden to .a, then the <div class="a"> does not occupy any vertical size. For example, if I set its background to red, it is not visible at all. Inspecting it with FireBug shows that it's there but of almost no vertical size.
To fix this, I found that I have to set overflow:hidden to .a. Then the first <div> goes over all its content.
Here is a real example:
<html>
<head>
<style>
.a { background-color: red; }
.b { background-color: red; overflow: hidden }
.floated-left { float: left; width: 100px; height: 100px; background-color: blue; }
</style>
</head>
<body>
<p>div with class a, that doesn't overflow:hidden:</p>
<div class="a">
<div class="floated-left">Hi,</div>
<div class="floated-left">Mom!</div>
</div>
<div style="clear:both"></div>
<p>div with class b, that does overflow:hidden:</p>
<div class="b">
<div class="floated-left">Hi,</div>
<div class="floated-left">Dad!</div>
</div>
</body>
</html>
Notice how Hi, Mom! does not get red background (no overflow:hidden), while Hi, Dad! does get red background (has overflow:hidden).
Can anyone explain this behaviour?
Here is screenshot of the example:
Thanks, Boda Cydo.
When you float elements they are taken out of the document flow. Among other things, this means that they have no impact on the dimensions of the parent element (although its width will determine where the floats are positioned on the horizontal axis). They do however impact positioning of siblings within the container depending on whether those sibling are inline or block level elements and whether they have width or not.
In order to make the height of the floats impact the height of the container you must have an element after them that clears them. However, what you are seeing here is actually a part of the CSS standard that you can use to clear floats without additional, non-semantic markup. The only issue is this behavior can vary slightly in older browsers and their css implementations. This effect is present with both overflow auto and overflow hidden but does not present with overflow visible. In IE < 6 you must have a width set on the containing element for it to work.
Hi, Mom does not get any background because the background comes from the a div, which is height 0 (or near 0). The inner divs are actually overflowing its bounds (which is what floats do by default).
The thing to remember with floats is that they don't have inherent height (when it comes to layout and determining the parent's height). Inline content simply flows around them. So without overflow: hidden the parent div has no height. No height means no background. The floats are still rendered but they go beyond the bounds of the parent div ie the content in the floats is outside the parent div.
Floated elements don't occupy any vertical space for clearing, there are a few ways to fix this, something like:
<div class="a">
<div class="floated-left">Hi,</div>
<div class="floated-left">Mom!</div>
<br style="clear: left;" />
</div>
Would clear after, and make the outer div have a vertical height. Set a border: solid 1px red; on .a to see this in action.
Alternative CSS only solution:
.a:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}
Per the spec for CSS basic box model:
Margins of a floated box do not
collapse with any other margins.
Margins of a box with ‘overflow’ other
than ‘visible’ do not collapse with
its children's margins.
By providing it the "overflow" property explicitly you have allowed the children to fit into this model, thus the b div no longer has bounds attached to its children. If you apply visible or inherit (which the parent of b is visible by default), the bounds return and the children divs define the margins.
http://www.w3.org/TR/css3-box/ (RE: Example X)