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Need help with 100% height float element


Question

Hey all. Right now I am trying to get the left navigation button to be a height of 100% because this will be my mobile CSS sheet.

I want it to go all the way down the white element that it is in.

The pink background color is there to help me see what's going on.

I'm using Firefox's web dev. inspector and it seems the #left-col is not height 100%, which means I won't be able to get the #prev-button-i to be height 100%, which is what I need.

My thought is maybe this is caused by the float? Maybe it really is at height 100% but it's just displayed differently because of the left float?

The site with the issue

http://alllols.com/index3.php

http://alllols.com/stylem.css

The main site with no issue (maybe it's useful?)

http://alllols.com/index.php

http://alllols.com/style.css

If anyone is curious, I just made this site for fun to learn PHP and MySQL :)

16 answers to this question

Recommended Posts

  • 0

Hard to figure out what is up because you seem to have height:100% on just about everything

Thank god I'm not the only one.

Could it be because, if when there is no float, it is at 100% height. So when it's floating, it is at 100%, we just perceive it to not be at 100% height?

  • 0

Thank god I'm not the only one.

Could it be because, if when there is no float, it is at 100% height. So when it's floating, it is at 100%, we just perceive it to not be at 100% height?

if you didn't abuse 100% height like this the height of all the elements should have been based on the content and there shouldn't have been any bug at all :p

Also don't use float on every single element either, float is usseless when there is no element next to it, and use other position types then static(default) if neccessary (absolute, relative, fixed).

  • 0

if you didn't abuse 100% height like this the height of all the elements should have been based on the content and there shouldn't have been any bug at all :p

Also don't use float on every single element either, float is usseless when there is no element next to it, and use other position types then static(default) if neccessary (absolute, relative, fixed).

Can you be more specific? I need that button to be 100% height because resolutions change. What am I supposed to do?

  • 0

Can you be more specific? I need that button to be 100% height because resolutions change. What am I supposed to do?

you mean the next and previous buttons right?

if so, try using fixed or absolute:


.nextbutton {
position: absolute;
top: 0;
bottom: 0;
right: 0;
width: 30px;
}
[/CODE]

  • 0

I don't want to sound rude but that's some nasty code here. I don't even know where to start. Maybe reading a book on css would be a good idea ...

prev-button-a cannot go all the way down the element it is in because there's a br after it. You should apply display:block to prev-button-a since you have a block level element inside it. Never put a block level element inside an inline element. The height 100% to prev-button-i will never ever do anything for 2 reasons. Its parent is an inline element (which doesn't support the height property). The height of an inline element is the height of the line (line-height). If you apply display:block to the parent of prev-button-i then it wont change anything cause the height of its parent (prev-button-a) is set to auto (ie the height of the content inside it which is min-height:100px).

<div id="left-col"> height is set to auto too. Like prev-button-a it will take the height of the content part of the normal page flow inside it. Its height will be 100px too if you remove the br (min-height:100px). Add to this the padding 60px at the top. Add to this the line-height of the br under it if you don't remove it. This element is floated. It is not part of the normal page flow. The reason <div id="left"> has an height is because of the central content (which is part of the normal page flow). As far as <div id="left-col"> goes its parent doesn't have any height other than min-height:220px.

Here's a quote from the css spec :

percentage

Specifies a percentage height. The percentage is calculated with respect to the height of the generated box's containing block. If the height of the containing block is not specified explicitly (i.e., it depends on content height), and this element is not absolutely positioned, the value computes to 'auto'.

So according to the css spec since the parent's height of <div id="left-col"> is not explicitely specified and <div id="col-left"> is floated then its height in % is then set to auto.

prev-button-i height is 100px because of min-height:100px. Remove this property and its height will then become 0px. You should try working with absolute positionning instead since absolu

  • 0

Here's something to help you start. It's not perfect by any mean since i did this really quickly in my break in about 10 min (with the previous post).

#left-col{
	width: 56px;
	height: 95%;
	position: absolute;
	left: 0px;
	top: 60px;
}

#prev-button-a{
	display: block;
	height: 100%;
}

#prev-button-i {
	height: 100%;
	width: 56px;
	background: url("./s_images/prev-button.png") no-repeat scroll 0% 0% rgb(255, 0, 255);
	min-height: 100px;
}

You should think about merging prev-button-i into prev-button-a. No reason to have both.

  • 0

It is indeed some messy css but rewriting it all might not be a option he would like to choose :p

That's why I posted the position absolute code, which should work no matter what the parent elements are like(ofcourse the parent elements shouldn't have position relative or fixed in that case)

  • 0

Thanks guys, I will try this later today. And LaP, why is my CSS so bad looking? Is there anywhere online that could help me with this?

You can read the specification. It's a daunting task but if you are serious about web design i think it's something that needs to be done once.

http://www.w3.org/TR/2011/REC-CSS2-20110607/

If you find reading the specification boring then a book is probably your best option. But i actually think the specification is easy to read and well explained.

After that you can find a good blog to learn about the quicks. I'm french so the blogs i'm reading are mostly french but i'm sure you can find good ones in english too. Here's one of the blog i read once a week.

http://www.alsacreations.com/

If you want to start with html5 there's a good free online book.

http://diveintohtml5.info/

http://html5please.com/

You should take a look at responsive web design too specially if you are into mobile web site.

http://alistapart.com/article/responsive-web-design

  • 0

Thanks guys, I will try this later today. And LaP, why is my CSS so bad looking? Is there anywhere online that could help me with this?

a large part is complexity. if you write the earlier rules only with what it ends up looking in mind without thinking forward (i.e. have a general plan of how you're laying everything out before writing any code) you often end up having to put in unnecessary properties to hack the result into what you want it to be. despite the name, too many cascades make it really difficult to work with because anyone troubleshooting can't tell head from toes.

  • 0

a large part is complexity. if you write the earlier rules only with what it ends up looking in mind without thinking forward (i.e. have a general plan of how you're laying everything out before writing any code) you often end up having to put in unnecessary properties to hack the result into what you want it to be. despite the name, too many cascades make it really difficult to work with because anyone troubleshooting can't tell head from toes.

This and the usual diseases called "classite" and "divite".

You don't have to put everything in a div with a class attached to it. When you have 5-6 levels deep of div it becomes as bad as using tables.

The web site is really simple yet the code is hard to read without a dom inspector.

Here's a good example :

&lt;div id="footer"&gt;&lt;div id="footer-text"&gt;&lt;span&gt; ? &lt;/span&gt;&lt;span&gt; ? &lt;/span&gt;&lt;span&gt; ? &lt;/span&gt;&lt;span&gt; ? &lt;/span&gt;&lt;span&gt; ? &lt;/span&gt;&lt;/div&gt;&lt;/div&gt;

There's no reason to have 2 divs here. The spans are also useless since all the text share the same visual style. The css of the span > a in this footer could be merged.

You should use meaningful tag as much as possible. a for link. p for paragraph. h for headers. etc etc etc

The div and span tags have no meaning. They do not inform the reader about the content. Ideally they should be used only when you need to group elements and apply a common visual style to them.

This topic is now closed to further replies.
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