Do not allow relative positioned div to overlap absolute positioned div - html

My actual issue is more complicated, but it boils down to this. How can I use CSS to disallow a relative positioned div to stack on an absolute positioned div.
Example of issue:
<div id="absolute"></div>
<div id="relative"></div>
div{
width: 100px;
height: 100px;
opacity: .5;
}
#absolute{
position: absolute;
background-color: red;
}
#relative{
position: relative;
background-color: blue;
}
Codepen
Is this possible with css? So the relative positioned div would be pushed down or to the side until it is not longer covering the other absolute positioned div. Basically the relative div would act as if the absolute div is relative.
To add a little detail of the nature do the issue:
I have a webpage with an absolutely positioned menu on the top and left. I then have a div in which I am injecting templates (Angular). The issue is that the templates end up under the menus. I have tried to apply a margin or padding, but is is messing up my bootstrap grid. So I was hoping the menu could be treated Iike it was relative in regards to the main div, but still stay in place.

When you use position:absolute, you're telling the browser layout engine that this element is removed from the layout of the page. You are specifying a manual position that will not impact the layout of the page in any way. Thus, you cannot both position it manually and have things layout around it.
You must pick one of the other, either don't use position: absolute so that it will participate in the layout of the page or make everything absolute and manually position things not to overlap.
There are some hybrid approaches where a item can be positioned absolutely in a container and the container itself is relative (not absolute) so that the container participates in the layout of the page and things will lay out around the container (and thus around the absolute positioned element if the container is set to be the right size), but this is really just a technicality as it puts the absolute positioned item into a non-absolute positioned container so it isn't really absolute positioned on the overall page any more.

It sounds like your problem would be solved by separating the elements and applying a float property. However, per your question, when your use the relative property, it allows you to set the position relative to it's parent. If the absolute positioned element is the parent, then your code is incorrect and keeping them separated would be a matter of hard-coding them to maintain a minimum distance from one another. However, it is not the parent then the elements have no relation to each other and you must explicitly define their position in order for them to not interact with each other. But again, it sounds like a situation to apply the float property.

Related

CSS absolute position orients on sibling rather than parent

I am a little confused about absolute positioning right now. I have always thought that if I position an element absolutely it would be positioned relative to it's parent element (in contrast to relative to it's usual position like relative positioning). During homework I now came across this situation and I'm confused:
<body>
<div> <!-- This is colored red in my example -->
...
</div>
<div style="position: absolute;"> <!-- This is colored green in my example -->
...
</div>
</body>
What I would expect:
What I got:
Of course when I set an actual position with left/right/top/bottom I get what I would expect from an absolutely positioned element. So is position: absolute just set to take the exact position it would be at without position: absolute when not specified otherwise?
To clarify:
"I have always thought that if I position an element absolutely it would
be positioned relative to it's parent element"
Nope. If an element has position: absolute;, it is positioned relative to the nearest parent in the DOM chain that has position: relative; or position: absolute; specified on it. If no parents have it (ie. they are all position: static, which is the default), then it is positioned relative to the document (page).
When using position: absolute, always:
Be aware of what parent you want it positioned relative to, and make sure that parent has position: relative; on it.
Specify one or more of the top/right/bottom/left attributes on the absolutely positioned object.
You are confused with the difference between position and display.
Position will change which element your element will be positioned relative to. In your case, your child div is now positioned to the body element. That's why it's on top.
Also you need to be aware that div is displayed as block, which means it will take all the width. If you want to align 2 divs left and right, the modern way is to use flexbox. The old way is float left/right.
I have made an article to explain CSS position in details:
https://www.youtube.com/watch?v=nGN5CohGVTI

Absolutely positioned elements with scrolling containers

An absolute positioned element is supposed to be removed from the element flow, and (so I understand) not able to make the document larger (creating scrollbars) but just go out of sight and out of mind.
But in my experiment when I offset an absolute element to the left I get scrollbars and to the right I get the expected behaviour. Why does it do this, and how could I get the behaviour I was expecting?
http://jsbin.com/bosajigapifu/6/edit
If you put the positioned absolute element into a container that is width: 100%, but overflow: hidden you can "push it into the void" that way. As long as its container does not go outside of the realm of the window it will not show scroll bars.
Elements:
<div id="container">
<div id="absolute"></div>
</div>
Styles:
<style>
#container{
width: 100%;
overflow: hidden;
}
#absolute{
position: absolute;
}
</style>
Absolutely positioned elements don't push other elements, but it does push out scroll-boxes if the element it's positioned relative to is the nearest scrolling ancestor.
The idea is that it's content and should be displayed. Kind of annoying tho when you want to position something outside a scroll container.
You may use position: fixed instead of absolute.
The diference is that it is not subject to any parent element, only to the viewport itself, but it does not create scrollbars when offset...
http://jsfiddle.net/t6g4421a/

Why do absolute elements stack up on each other instead of stacking one after the other?

How can get both #row1 and #row2 in the following code to be visible, one after the other vertically, as if there wasn't any absolute/relative positioning involved (though without removing the positioning properties)? I.e. having the two .row <div> to appear as "normal" block elements.
body { position:relative; min-height: 2em; width: 100%; }
.container {position:absolute;}
.row {position:relative;}
.col1, .col2 {position: absolute;}
<body>
<div class="container">
<div id="row1" class="row">
<div class="col1">Hello</div>
<div class="col2">World</div>
</div>
<div id="row2" class="row">
<div class="col1">Salut</div>
<div class="col2">le monde</div>
</div>
</div>
</body>
(Sample also available as a fiddle.)
I need the elements to have the positioning provided in the CSS rules, for reasons excluded here.
The content is programmatically dynamic; I don't know the elements' heights beforehand, so a solution can't be based on specifying an absolute length (e.g. 'px') anywhere.
Well you have some weird wishes here so let me explain you what those positions really mean in CSS and how they work, using position: relative; is just like using static position, the difference is making an element position: relative;, you will be able to use top, right, bottom and left properties, though the element will move, but physically it will be in the document flow..
Coming to position: absolute;, when you make any element position: absolute;, it gets out of the document flow, hence, it has nothing to do with any other element, so in your example
you have .col1, .col2 {position: absolute;} which are positioned absolute and since both are out of the document flow, they will overlap... Because they are already nested under position: absolute; parent i.e .container and since no width is assigned, it will take the minimal width and hence, your elements overlap, if you cannot change your CSS(which according to me doesn't make any sense why you can't change) still if you want, than you can do is this..
Demo (Without removing any of your position property) And this is really dirty
For the s characters, it will be at the top as your container element is out of the flow, and hence, no height will be considered in the document flow, unless and until you wrap that s in some element, and bring it down with, margin padding or CSS Positioning.
CSS Positions Explained
As I commented, here are few examples of how CSS Positioning actually works, to start with, there are 4 values for position property i.e static which is the default one, relative, absolute and fixed, so starting with static, nothing to learn much here, elements just stackup one below the other unless they are floated or made display: inline-block. With static positioning, top, right, bottom and left won't work.
Demo
Coming to position: relative; I've already explained you in general, it's nothing but same as static, it stacks up on other element, it is in the document flow, but you can tweak the elements position using top, right, bottom and left, physically, the element stays in the flow, only position of the element is changed.
Demo 2
Now comes absolute which generally many fails to understand, when making an element absolute it gets out of the document flow, and hence it stays independent, it has nothing to do with other elements positioning unless it's overlapped by other position: absolute element which can be fixed using z-index to change the stack level. The main thing to remember here is to have a position: relative; container so that your absolute positioned element is relative to that relative positioned element, else your element will fly out in the wild.
It's worth noting that position: absolute; element when positioned absolute; inside an absolute positioned parent element, than it is relative to that element and not relative to the grand parent element which may be positioned relative
Demo 3 (Without position: relative; container)
Demo 4 (With position: relative; container)
Last is position fixed, this is same as absolute but it flows along when you scroll, it's out of the document flow, but it scrolls, also, position: fixed; element cannot be relative to any container element having any type of position, not even relative, position fixed element is always relative to the viewport, so designers use position: absolute; when they want to have a fixed position behavior but relative to parent and tweak the top property onScroll.
Demo 5
What you want, is not possible without modifying the CSS position property. However, what you can do without touching the existing CSS, is overriding it with a more specific selector
.row .col1, .row .col2 {
position: relative;
}
See JSFiddle
when position:relative is used, the page layout will occur normally before being offset by top, left values, however position:absolute will ignore the document flow. The relative ones will work with no changes but absolute must be changed
.col1, .col2 {display:inline-block;}
http://jsfiddle.net/C4bQN/
EDIT: Depending on your circumstances, maybe you can wrap your table in an absolute positioned div then use normal document flow within the table?
<div class="absolute-wrap">
<div class="row">
<div class="col"> </div>
</div>
</div>

How to have a div be positioned relative to its parent, but float above it's siblings?

I have one div - the #container - that stretches across the window, filled with a graphic. I need a bar to float over the container div on the right side. If I use position:absolute and right:0, the div is positioned according to the window, not the #container div.
If I use position:relative, then the div is positioned according to the #container div but still takes up space and won't be hovering over the #container content.
Here is a JSFiddle that I made with my attempt.
http://jsfiddle.net/y8LCu/
NOTE that I do not want to use float:right, because that would keep the side div in the flow of the content, which I do not want.
I think I got it the way you wanted it?
http://jsfiddle.net/y8LCu/9/
You needed to make the parent position: relative and if you don't want the overflow you need overflow: hidden.
position:absolute; allows you to position an element compared to any positioned ancestor.
<div class="parent">
<div class="child">
</div>
</div>
.parent { position : relative; }
.child { position : absolute; }
Now, child will position itself based on the parent.
If the parent doesn't have a position set, then it will look at the position of the grandparent...
...and on and on, and if none of them have a position set, then it will look at the position of the actual web-page.
Also, if you have multiple positioned elements (whether relative/absolute/fixed) near the same place, and you want them to overlap in an order you set in CSS, and not in the order of which is set on the page last...
...then you also need to start using z-index (which only works on positioned elements).
The higher it is, the more stuff it stacks on top of.
Set the parent's position to relative
#container
{
position:relative;
}

How to put a static div on top of an absolute position div?

I am building a small web application.
I have two divs. One is absolute and the other is static.
I am trying to position my static div on top of my absolute one, so that it remains the top most item.
Very simple Code Sample:
http://jsbin.com/efuxe3/edit
How can this be done?
Edit:
I have been using z-index. It seems to have no effect.
z-index doesn't apply to static elements.
According to this page:
This property specifies the stack
level of a box whose position value is
one of absolute, fixed, or relative.
If you make your div relative instead, you can use z-index to determine the order.
position: relative positions the element relative to its default (static) position, so if you don't specify a top, bottom, left or right then there'll be no difference between static and relative other than that relative allows you to use z-index to move your element up the stack.
Edit: based on your code sample, here's a working demo.
Edit 2: based on Nathan D. Ryan's suggestion in the comments below, you could also apply a negative z-index to your absolutely-positioned div. This would move it behind everything else on the page that didn't have a lower z-index defined.
Rather than placing the statically positioned element over the absolutely positioned element, you can place the absolutely positioned element behind the statically positioned element. You can do this by setting the z-index of the absolutely positioned element to a negative value. However, as #Town mentioned, this will also place the absolutely positioned element behind everything else in the normal flow.
You can apply a negative z-index to the other elements placing them behind the static div. This can be applied directly to the other elements or you can use
*:not(connectedObjects){
z-index:-1000000000000000000000000000;
}
But this does not work in internet explorer
You could have a second absolutely positioned div to contain your statically positioned elements:
<div id="container">
<div class="underlay">
I want this to appear under my static items.
</div>
<div class="item_container">
<div class="item">blah</div>
<div class="item">yada</div>
<div class="item">foo</div>
<div class="item">bar</div>
</div>
</div>
And your css is
.underlay {
position: absolute;
z-index: 0;
}
.item_container {
position:absolute;
z-index:10;
top: 0;
left: 0;
height: 100%;
width: 100%;
}
.item {
position: static;
}
if by top you mean z-Index, you can set the style of that div with a higher z-index
div.divClassName {
z-Index:100;
}
edit:
you can change the z-index of your div, with absolute positioning to a negative, but then you will have to do so for every other element.
Unless you really have a really good reason to using positioning to static you can change it
to relative, and the z-index will have an effect.io have tried it in your code sample and it works fine;
Work with z-index attribute. The z-index of the object which should be at front must be higher than the other ones.