Sass : A simplified way to write CSS – Part 3

This is the third post in series on SASS. In my first post, I briefly discussed about SASS and Variables. In my second post I discussed about operators and some important inbuilt functions. Links of earlier posts are

Sass : A simplified way to write CSS – Part 1

Sass : A simplified way to write CSS – Part 2

In my today’s post, We’ll discuss nesting, mixins and inheritance with SASS.

Nesting is very common practice in programming languages and supported in all the major languages in one or other way. Even if we see the normal HTML page then we find that the whole page is structured in a nested manner. Similarly we find it in XAML or even normal aspx page as well. But it is not supported in CSS.

Sass supports nesting. Let’s see via an example

NestedIf we see above code then we see the whole section is defined for navigation bar in a nested manner. Now let’s see the above CSS when it renders on client and looks like

nestedrenderedThe rendered version is above. Here the Sass pre-processor processes the file and converts it that can be understood by the browser. Here all the classes are rendered in separate blocks as required.

Now let’s move to other topic that is Mix-ins. In our CSS files, many times we write the same css style at several places. If we require to change the same then we need to update the same at several places. Let’s see it via an example

mixin-codeIn above code, we have defined a mix-in variable named custom-style and the same variable, we have used in another classes (class1, class2, class3). To use mix-in variable at another places,  use @include keyword as above in the code. Mix-ins can be used in another scenarios as well.

SASS also supports Inheritance. @extend keyword allows us to use the properties of another class. Let’s see it via an example

In this example, say we want to show messages based on response and change the background color based on response type like on error, warning, success etc. This could be written as

ineritanceHere if we see the above code then we find that we have created a class .message and later we used this class in other classes success, error and warning with extend keyword. Just let’s see how it gets rendered.

renderedinheritanceAs it clearly shows that the classes success, error and warning has power of .message class as well. So we can easily use the inheritance feature as well.

So we have seen in last three articles that Sass provides us the capability to use our normal programming techniques that we are using since long, can be used with CSS. This helps us in writing better and organized manner and also helps not to devote much time on normal CSS.

Hope you all have enjoyed this post.

Cheers,
Brij

Advertisements

Sass : A simplified way to write CSS – Part 2

In my last post, I have discussed briefly about Sass (Syntactically awesome style sheets) and Sass variables with examples. You can find the last post link below.

Sass : A simplified way to write CSS

Now in today post, we’ll discuss about operators and inbuilt functions provided by Sass.

Sass supports math operators like +, -, *, /, and %. There could be various scenarios using operators like say we have created some basic variables say a variable with font size as 9px. Now in our application we may require various font size based on locations like top, middle, different headers and other sizes for different sections which can be derived from the base font size. Similarly that can be done while using colors and other various case.

Let’s see it via an example. So my scss file is as

operator-1

If we see above, I have created a variable $base-font-size as 9px then used the same variable to derive font size for multiple classes h1, h2, h3. In h1, * (multiplication) operator is used, in h+ (addition) operator is used and in h3 % opertaor is used. Here if we see the variable in not a pure numeric variable, it contains px as well. But it is taken care while processing the scss file so we dont need to care about it and we can use any other —- as well. So let’s run the code and see the generated css file

operator-2

Lets see another example

$basepadding : 1%;
.thinpadding
{
    padding : $basepadding;
}
.thickpadding
{
    padding : $basepadding*5;
}
.superthickpadding
{
    padding : $basepadding*10;
}
.normalpadding
{
    padding : $basepadding*2;
}

Here I have defined a base padding and then use the same variable to define the different padding  classes that can be used to define padding at various places.

We can use these operators at various places based on the requirement.

SASS also provide a list of inbuilt functions that can be used for writing the scss which include color functions like darken, lighten, hue. Let’s see an example

We can have a base color and just we can use the same color or lighter color or darker color or any other color in our application. So it can be used as

$basebackgroundcolor : #EDF0F5;

.darkbackground
{
    background : darken($basebackgroundcolor, 50%)
}
.lightbackground
{
    background : lighten($basebackgroundcolor, 25%)
}

Here in first class we have used the darken color which produces the dark color by 50% while the second one produces the light color by 25%.
There are many other color functions and host other Number functions, List functions, String functions etc are available. For complete list, please refer the documentation here http://sass-lang.com/documentation/Sass/Script/Functions.html

In next post, I’ll discuss about Nesting and Mixins with examples.

Cheers,
Brij

Sass : A simplified way to write CSS

This is the age of revolutions. For me at least as a web developer, I am seeing it last few years. Once AJAX came into the market and become popular, it changed the whole web development and web experience as a user. Microsoft came up with the whole new AJAX control toolkit to make the UI very UI intuitive. The Client side technologies like JavaScript, CSS etc are always pain for a web developer like me. But jQuery gave a new flavor to Client side scripting and now get used in almost all web projects. There are many new plugins of jQuery came into existence and few of them got widely used.

And now it’s turn to CSS, I faced tough time working with CSS but new things are coming up. Microsoft always embraces these technologies so that the developer gets the benefit of these technologies and get the first class experience in their Visual studio itself. Today we’ll talk about SASS ( Syntactically awesome stylesheets).

So What is Sass?

As the full form of Sass it self says (Syntactically awesome style sheets). As per the sass website it is “Sass is the most mature, stable, and powerful professional grade CSS extension language in the world“. One does not need to learn any new technology instead uses the existing technology/learning and use that to write wonderful CSS in a very simple way.

So how does it actually works?

A Sass file is compiled into an normal CSS file while execution. When we run the application, the sass file get converted to css file and returned to the browser.

Next how to use Sass?

As now Microsoft introduces a new and very powerful tool Nuget to install packages/plugins for the project. It’s very simple and easy to install. In this example, I’ll be using ASP.NET, So I have installed the package SassAndCoffee.AspNet via nuget as

Go to -> Package Manager Console and type

Install-Package SassAndCoffee.AspNet

else you can also install via Manage Nuget Package.

It adds few dlls and some config entries in web.config. After installing it, It adds in HTTPModule which looks for any incoming request for all css request and tries to find the css file and if css file does not available then it looks for scss file and if it is available the process the scss file and convert it into css file and return it. So your page does not need to know about all the behind the seen processes, you just need to include the normal css file in your project.

.Sass provides us the capability to use programming language feature for writing StyleSheet. SASS provides us two syntaxes. The new syntax is known as SCSS (Sassy CSS) that is easy to write and also a superset of CSS3. I’ll be using it our posts. The file extension for it is scss. While the other older one is normal sass  and known as indented css and now is obselete.

Let’s see the basic feature of Sass. Sass provides us the capability

  • Declaring Variables
  • Allows Operations
  • Allows Nesting
  • Mixins
  • Extend/Inheritance

Doesn’t it look interesting? You get the basic features of any programming language for your css and you dont need to learn anything for this to use except some basics about how to use it.

So in this post, we’ll see the Variable and operations.

Variables – It means we can created the variables and use it in our file wherever require similar like in C# or other language. So variables can be created as

$common-font: verdana;
$common-font-size : 9px;
$basecolor : #000;
$custom-border : solid 5px, #000;

Variable could contain single value or contain list of items as $custom-border contains multiple values. So in my application, I have created a file with extension as scss ( Custom.scss) and that contains

first

Now if we run the application and access the file with URL

http://localhost:64983/style/custom.css

then it returns the processed css file as

secondAll the processing like here replacing with actual values, is done at server side. So it does not affect any client side catching.

If we have here option to create variable, then it should also provide the capability to do some operation over it. Yes, we can do it. We’ll discuss this in next part.

Also if we try to access the URL

http://localhost:64983/style/custom.scss

then it returns the error

HTTP Error 404.3 – Not Found

Hope you have enjoyed this post. In next post, I’ll discuss about various operations and few other examples.

Cheers,
Brij