I'm trying to understand this code in order to both crop and center an image.
I think I've understood most of it, but I'm still not figuring out why I need this:
.img-crop img{
/* removes(sorta) image from the flow */
padding-left: 100%;
margin: -100% -100%;
}
I think margin: -100% -100% is for centering the image both vertically and horizontally, but why is it placed on the left of the container (and therefore: why do I need that padding-left: 100%)?
I think I figured out how it works. here you can find an example I tried to write for you from scratch. The image has been replaced by a div, but since they are both displayed as inline-block, the last one is convenient for changing heights and play with it.
Let me say it's quite useful if you don't want to use jquery to heavily manipulate all your DOM! Crop and centering just in a bunch of css rulesets.
Related
I was searching around for a way to vertically center a div in a container. I found a few different ways, but all of them seemed to be very "hacky".
My question is, why is there not just a css property, such as align-vertical that can simply be set to center to center the content? It seems like adding this to css would make so many things much easier.
I am assuming there must be a reason why something like this is not implemented, and I would like to hear if anyone has any idea why.
It's because how browsers traditionally work.
In a browser, by default, the content scrolls vertically. The viewport width is well defined (width of the device), but the viewport height can be one or two times the height of the device, or can even be infinite (as in infinite scrolling).
Traditionally blocks were meant to be horizontally oriented. You place a div and it's automatically occupying 100% of the width of the parent. But its height value is contrained to its content.
If you do
.mydiv {
background: red;
width: 100%;
height: 100%
}
Nothing changes, since divs have already 100% of width, and it can't calculate the height, since it doesn't know how far the viewport will go. You need to add:
html, body {
height: 100%;
}
to tell the browser to use the device height as the 100% value.
That's why horizontal center is easy: you know what the boundaries are, and how to center the element. But vertical center is more complicated, that's why (before flexbox), you need to resort to absolute positioning or hacks.
Flexbox allows you to render content horizontally or vertically, so it's prepared to handle centering along two axes.
If you want to read more about this, I suggest the spec:
Visual formatting model
Visual formatting model details
#outerDiv{
display:flex;
width:100%;
height:200px;
background:#ccc;
align-items:center;
}
#innerDiv {
background:#aaa;
width:80%;
margin:0 auto;
}
<div id="outerDiv"><div id="innerDiv">Hello</h1></div>
Run the script and the div remain in the center.
You can mix and match the combination like this.
Earlier you need to play with the height of the parent container and self height.
But with flex it becomes easy.
If I'm trying to center an element I do the following -
*parent-item {
margin: 0 auto;
width: 100%;
display: block;
It's important to define the width of the element you are centering.
So I've read a couple of CSS guides and understood most properties, but I still can't position elements PROPERLY.
What I mean by properly: right now I position stuff using specific values ofmargin, margin-right, margin-left, padding, (margin-left:50px), etc... What this means is that my divs are all positioned properly when I view it in my own computer with a specific resolution.
So I hope this isn't too general, but how do I position stuff in a way that they will be in the same relative spot in the page, for every resolution/page size, no matter who and what views it (I guess if it's the same for 99% of cases it's also a good start).
A bit more specific: which properties can I use to position elements in the manner I described?
Here's a link of one of my little projects which are badly positioned (it's all good in my screen, but not so much on others:
http://kash.hostzi.com/utopia/minesweeper.html
check out #gameTable's css for example - I wanted to center that and did it in a horrible way.
In your linked example, it looks like you want the gameboard to be centered. If it's a block-level element, such as a div or table, and you want to center it, you can use this on the element itself:
margin-left: auto;
margin-right: auto;
If it's an inline element, and you want to center it, you can use this on the parent element:
text-align: center;
If you weren't trying to center it, but just want to have the position scale with the screen size, do something like this:
margin-left: 10%;
margin-right: 10%;
If you want the position to scale with the font size, do something like this:
margin-left: 10ex;
margin-right: 10ex;
You can start using percentages. Like:
margin-left: 20%;
margin-right: 20%;
and it will be margined depending on the window(the element in which it is) size.
I'm trying to set up a responsive header that takes an image and resizes it to the browser – easy enough. What I can't manage to achieve is centring the image vertically within it's container (in this case an a element)
See example:
http://jsfiddle.net/jwoodcreative/tUW3k/
I've tried a few css tricks that havent worked and some jQuery. Either type of solution would suit if anyone knows of one.
You can always use the top:50%, bottom: 50% trick like here: jsfiddle v13
.outerElement {
position: relative;
height: XXpx;
top: 50%;
}
.innerElement {
position: absolute;
bottom: 50%;
}
This works, because the height of the innerElement is not the same as the one of the outer Element, so you can center your element (if the heights were identical, you'd just position it to pos:0 again)
Like this? I've changed the image to be a background-image, which can be centered very easily in CSS. To make sure the link is shown, I have added a non-breaking space ( ). I think this is what you want, right?
You can change the appearance of the image more by looking here, at the documentation of the background property.
I have been trying for an hour to get a list in a sidebar of WordPress to have a negative margin. Fooled around with margins, padding, sidebar placement in the php files... But the link images just keep disappearing behind the background.
Here's the page where I'm working: http://kirahenschel.com/
This is what I am trying to achieve:
http://emgraphics.net/kira/idea2-11.jpg
Ideally I'd also like that sidebar to be a finite height so the white boxes on the bottom spread, but I can cope with them being off to the right.
Anyone have any ideas? Neg margins are working fine on the logo, so it is just a list thing?
Thanks
If you're merely trying to get the list to be bumped to the left, why not use a CSS positioning property? Negative margins can get really wonky, and are (most likely) unneeded in this application.
#nameoflistdiv {
left: -20px;
}
You may also need to change the value of your div's position element, but this will bump your div and everything in it left, overlapping the container div.
If that doesn't answer your question, can you post the HTML and CSS you are using? The CSS code
margin-left: -20px;
really should work in this application as well, so show us what you've got.
Your negative margin is working as expected. The reason the images are getting cut off is because you have set overflow:hidden on the #main container. If you remove that property your images will appear.
#main {
background: url("images/blend.png") repeat-x scroll center top #2765CA;
clear: both;
height: 630px;
overflow: hidden; /* delete this line */
padding: 0;
}
Just a quick question regarding CSS positioning. I have several "segments" on my site which are 100% wide (fills the screen), and I want them floated next to each other. So only the first one will be visible, the other ones will be off-screen. I've tried playing around with positions and the overflow property without luck. Right now they just pop down below each other instead of floating.
This would work perfectly if the elements did not exceed the screen width, but as they do, they just pop down as I said earlier. I've tried setting a huge width to the "wrapper", something like 99999px. And then setting the segments to 100%, but that will just fill the whole 99999px width instead of the screen.
Any ideas?
JSFiddle example: http://jsfiddle.net/9xGPb/
Do you mean like this?
Example Fiddle: here
I used my favourite alternative to floats, inline-blocks
if you actually take it out of the fiddle it has some pretty (gaudy?) colours which show that it allows for the min-width: 900px; on the centered_content div to work too, and I removed the absolute positioning for the menu so the content would go below it, for demo only but you may find it useful..
let me know if any good or if you have any questions
Updated with some jQuery and to make corrections for default word-spacing
New Example: here
re: the IE6/7 hack rightly mentioned in the comments;
.segment {
display: inline-block;
overflow: hidden;
width: 0;
}
.segment {display: inline !ie7;}
needn't be a "parse hack" if that's your preference as long as that second rule is given to [lte IE 7] somehow, and separately at that it cannot be combined into the original rule with the * hack or anything, it won't work.. has to be in a separate ruleset.
I discovered word-spacing might be a problem if relying on width to hide, the natural behaviour of inline blocks is to put 3-4px between the elements like the space in between words, the workaround to this is to correct the word-spacing on the wrapper
.segment-wrapper {
white-space: nowrap;
word-spacing: -4px;
}
then restore it normal for the actual content divs, same place as you would restore the normal wrapping behaviour
.centered_content {
width: 900px;
margin: 0px auto;
background: #fcf;
white-space: normal;
word-spacing: 0;
}
and last, apart from this was fun.. there's 2 effects in that new fiddle - uncomment and comment the other.. forgive me I was playing! :)
The meaning of float is to try to float to the right or left unless there is not room for it.
This means that you cannot ever float an element off the page.
If you need to keep the element off the page, you will need to use a different positioning mechanism like position: absolute.
It sounds like you're creating a horizontal one-page portfolio. I've recently been working on something similar.
Using your fiddle I've set the .segment class to
.segment {width:90%;height:90%;position:absolute;}
and then offset each left positioning further off the screen
#home {background-color:red;left:5%;}
#work {background-color:yellow;left:105%;}
#portfolio {background-color:green;left:205%;}
#contact {background-color:blue;left:305%;}
http://jsfiddle.net/9xGPb/2/
I also added some jQuery logic to switch views for the divs.
I'm still not entirely sure which segments you want to start off the page but this jsfiddle uses positioning to shove the #two div off to the right: http://jsfiddle.net/EdAZP/1/
Which part of your example did you want to start off the page?
Did you try to just hide the other elements and toggle them with some javascript (jQuery is much easier)?
http://api.jquery.com/toggle/