Please explain to me when to use the classes container
and row
. I\'m not sure because the documentation of Bootstrap is quite unclear about this pa
Container
The container provide the width constraints on responsive widths. When the responsive sizes change, it’s the container that changes. Rows and columns are all percentage based so they don’t need to change. Note that there is a 15px margin on each side, canceled by rows.
Rows
Rows should always be in a container.
The row provides the columns a place to live, ideally having columns that add up to 12. It also acts as a wrapper since all the columns float left, additional rows don’t have overlaps when floats get weird.
Rows also have a 15px negative margin on each side. The div that makes up the row would normally be constrained inside of the containers padding, touching the edges of the pink area but not beyond. The 15px negative margins push the row out over top of the containers 15px padding, essentially negating it. Furthermore, rows ensure you that all of the divs inside of it appear on their own line, separated from the previous and the following rows.
Columns
The columns now have 15px padding. This padding means that the columns actually touch the edge of the row, which itself touches the edge of the container since the row has the negative margin, and the container has the positive padding. But, the padding on the column pushes anything inside the column in to where it needs to be, and also provides the 30px gutter between columns. Never use a column outside of a row, it won’t work.
For more information, I suggest you to read this article. It is really clear, and explain well how Bootstrap's grid system works.
Class 'container' wraps the content within to center of view port. Entire content with in body tag can be placed in results the page displayed of specified width in center of page.
Class 'row' is used when you need to place content in columns with in a row, you can have upto 12 columns in total in each row.
I was wondering about the same and to understand that I went through the bootstrap.css
of version 3. The answer lies in from line no. 1585 to 1605. I'll post those lines here for better understanding as below.
.container
{
padding-right: 15px;
padding-left: 15px;
margin-right: auto;
margin-left: auto;
}
@media (min-width: 768px) {
.container {
width: 750px;
}
}
@media (min-width: 992px) {
.container {
width: 970px;
}
}
@media (min-width: 1200px) {
.container {
width: 1170px;
}
}
Whole of the code is self explanatory. However, to elaborate on this, container would take 750px
if screen width is between 768px
and 992px
and so forth as the code shows. Now, for common screen resolution of more than 1200, container would take 1170px
, but subtracting the padding of 30 px
(15px+15px
), the effective space left is 1140px
, which is centered on the screen as the margin of left and right is set to auto.
Now, in case of class="row"
, there is below code:
.row {
margin-right: -15px;
margin-left: -15px;
}
So, if row is inside the container, it would effectively snatch the padding of 15px each side from the container and use the full space. But if the class row is inside the body tag, it would tend to move out of the visible area into both the left and right side of the browser due to negative margins.
I hope it was made clear.
In the traditional CSS practices you would probably use the following classes:
wrapper, header, navigator, contents, footer
the usage of the above classes can be like this example:
<body>
<div class="wrapper">
<div class="header">
</div>
<div class="navigator">
</div>
<div class="content">
</div>
<div class="footer">
</div>
</div>
</body>
In bootstrap you can use if you wish or if you are used to the above template the bootstrap classes like this example:
<body>
<div class="container">
<div class="col-md-12">
<h1>Header</h1>
<p>Header contents goes here</p>
</div>
<div class="col-md-12">
<nav role="navigation" class="nav navbar">
<h1>Navigation</h1>
<p>Navigation contents goes here</p>
</nav>
</div>
<div class="col-md-12">
<div class="pagination">
<h1>Page contents</h1>
<p>Webpage contents goes here</p>
</div>
</div>
<div class="col-lg-12">
<h1>Footer contents</h1>
<p>footer contents goes here</p>
</div>
</div>
</body>
For the row class you can use row class when you want to design tabular layout for the page, but when you want to display data in table format you should use table class, but the table will not be responsive.
To create tabular layout which different from data tables use the row class like in this example:
<body>
<div class="container">
<div class="row">
<div class="col-sm-4" >.col-sm-4</div>
<div class="col-sm-4" >.col-sm-4</div>
<div class="col-sm-4" >.col-sm-4</div>
</div>
</div>
</body>
You must try to avoid using table-based layout and try to use responsive tables like described here
container
is a container of row
elements.
row
elements are containers of columns (the docs call it grid system)
Also, container
sets the content's margins dealing with the responsive behaviors of your layout.
Thus the container
class is often used to create 'boxed' contents based on the style guidelines of the Bootstrap project.
If you want to go "out of the box" creating a full width grid you can use only row
elements with columns inside (spanning the usual 12cols total).
The container
and row
classes are for elements inside the body.
So a basic layout would be:
<html>
<body>
<div class="container">
<div class="row">
<div class="col-md-xx"></div>
...
</div>
<div class="row">
<div class="col-md-xx"></div>
...
</div>
</div>
</body>
</html>
For a boxed responsive layout.
If you omit the container
you'll get a full-width layout.
Jumbotron is a good example of the container
behavior. If you put a Jumbotron element in a container
element it has rounded borders and a fixed width based on the responsive width.
If the Jumbotron is outside a container, it spans full-width without borders.