I have variables $person-color and $animal-color in a separate variables.scss file which I want to use in my main.scss file.
What I want to achieve is the following CSS:
.person-container {
background: blue;
}
.animal-container {
background: red;
}
My SCSS looks like below:
$items: person animal;
#each $item in $items {
.$item-container {
background: #{$item}-color;
}
}
This won't work. But I want to expand the value of the variable in the string #{$item}-color. Is there a way to get the output above without using a map?
Partials need to start with an underscore ex. _variables.scss or else it will compile into a .css
_variables.scss
$person: red;
$animal: blue;
main.scss
#import 'variables';
$items: person $person, animal $animal;
#each $item in $items {
$key: nth($item, 1);
$value: nth($item, 2);
.#{$key}-container {
background: $value;
}
}
Edit: Now should give you the right results!
Related
I'm trying to use string interpolation on my variable to reference another variable:
// Set up variable and mixin
$foo-baz: 20px;
#mixin do-this($bar) {
width: $foo-#{$bar};
}
// Use mixin by passing 'baz' string as a param for use $foo-baz variable in the mixin
#include do-this('baz');
But when I do this, I get the following error:
Undefined variable: "$foo-".
Does Sass support PHP-style variable variables?
This is actually possible to do using SASS maps instead of variables. Here is a quick example:
Referencing dynamically:
$colors: (
blue: #007dc6,
blue-hover: #3da1e0
);
#mixin colorSet($colorName) {
color: map-get($colors, $colorName);
&:hover {
color: map-get($colors, #{$colorName}-hover);
}
}
a {
#include colorSet(blue);
}
Outputs as:
a { color:#007dc6 }
a:hover { color:#3da1e0 }
Creating dynamically:
#function addColorSet($colorName, $colorValue, $colorHoverValue: null) {
$colorHoverValue: if($colorHoverValue == null, darken( $colorValue, 10% ), $colorHoverValue);
$colors: map-merge($colors, (
$colorName: $colorValue,
#{$colorName}-hover: $colorHoverValue
));
#return $colors;
}
#each $color in blue, red {
#if not map-has-key($colors, $color) {
$colors: addColorSet($color, $color);
}
a {
&.#{$color} { #include colorSet($color); }
}
}
Outputs as:
a.blue { color: #007dc6; }
a.blue:hover { color: #3da1e0; }
a.red { color: red; }
a.red:hover { color: #cc0000; }
Sass does not allow variables to be created or accessed dynamically. However, you can use lists for similar behavior.
scss:
$list: 20px 30px 40px;
#mixin get-from-list($index) {
width: nth($list, $index);
}
$item-number: 2;
#smth {
#include get-from-list($item-number);
}
css generated:
#smth {
width: 30px;
}
http://sass-lang.com/docs/yardoc/file.SASS_REFERENCE.html#lists
http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#list-functions
Anytime I need to use a conditional value, I lean on functions. Here's a simple example.
$foo: 2em;
$bar: 1.5em;
#function foo-or-bar($value) {
#if $value == "foo" {
#return $foo;
}
#else {
#return $bar;
}
}
#mixin do-this($thing) {
width: foo-or-bar($thing);
}
Here's another option if you're working with rails, and possibly under other circumstances.
If you add .erb to the end of the file extension, Rails will process erb on the file before sending it to the SASS interpreter. This gives you a can chance to do what you want in Ruby.
For example: (File: foo.css.scss.erb)
// Set up variable and mixin
$foo-baz: 20px; // variable
<%
def do_this(bar)
"width: $foo-#{bar};"
end
%>
#target {
<%= do_this('baz') %>
}
Results in the following scss:
// Set up variable and mixin
$foo-baz: 20px; // variable
#target {
width: $foo-baz;
}
Which, of coarse, results in the following css:
#target {
width: 20px;
}
I came across the need to reference a colour dynamically recently.
I have a _colours.scss file for every project, where I define all my colours once and reference them as variables throughout.
In my _forms.scss file I wanted to setup button styles for each colour available. Usually a tedious task. This helped me to avoid having to write the same code for each different colour.
The only downside is that you have to list each colour name and value prior to writing the actual css.
// $red, $blue - variables defined in _colours.scss
$colours:
'red' $red,
'blue' $blue;
#each $name, $colour in $colours {
.button.has-#{$name}-background-color:hover {
background-color: lighten($colour, 15%);
}
}
I needed to use dynamic color values in sass variables.
After lots of search, I applied this solution:
In application.html.erb:
<style>
:root {
--primary-color: <%= current_client.header_color %>;
--body-color: <%= current_client.footer_color %>;
}
</style>
In variables.sass:
$primary: var(--primary-color);
And boom you are good to go!
Reference: https://medium.com/angular-in-depth/build-truly-dynamic-theme-with-css-variables-539516e95837
To make a dynamic variable is not possible in SASS as of now, since you will be adding/connecting another var that needs to be parsed once when you run the sass command.
As soon as the command runs, it will throw an error for Invalid CSS, since all your declared variables will follow hoisting.
Once run, you can't declare variables again on the fly
To know that I have understood this, kindly state if the following is correct:
you want to declare variables where the next part (word) is dynamic
something like
$list: 100 200 300;
#each $n in $list {
$font-$n: normal $n 12px/1 Arial;
}
// should result in something like
$font-100: normal 100 12px/1 Arial;
$font-200: normal 200 12px/1 Arial;
$font-300: normal 300 12px/1 Arial;
// So that we can use it as follows when needed
.span {
font: $font-200;
p {
font: $font-100
}
}
If this is what you want, I am afraid as of now, this is not allowed
I'm trying to use string interpolation on my variable to reference another variable:
// Set up variable and mixin
$foo-baz: 20px;
#mixin do-this($bar) {
width: $foo-#{$bar};
}
// Use mixin by passing 'baz' string as a param for use $foo-baz variable in the mixin
#include do-this('baz');
But when I do this, I get the following error:
Undefined variable: "$foo-".
Does Sass support PHP-style variable variables?
This is actually possible to do using SASS maps instead of variables. Here is a quick example:
Referencing dynamically:
$colors: (
blue: #007dc6,
blue-hover: #3da1e0
);
#mixin colorSet($colorName) {
color: map-get($colors, $colorName);
&:hover {
color: map-get($colors, #{$colorName}-hover);
}
}
a {
#include colorSet(blue);
}
Outputs as:
a { color:#007dc6 }
a:hover { color:#3da1e0 }
Creating dynamically:
#function addColorSet($colorName, $colorValue, $colorHoverValue: null) {
$colorHoverValue: if($colorHoverValue == null, darken( $colorValue, 10% ), $colorHoverValue);
$colors: map-merge($colors, (
$colorName: $colorValue,
#{$colorName}-hover: $colorHoverValue
));
#return $colors;
}
#each $color in blue, red {
#if not map-has-key($colors, $color) {
$colors: addColorSet($color, $color);
}
a {
&.#{$color} { #include colorSet($color); }
}
}
Outputs as:
a.blue { color: #007dc6; }
a.blue:hover { color: #3da1e0; }
a.red { color: red; }
a.red:hover { color: #cc0000; }
Sass does not allow variables to be created or accessed dynamically. However, you can use lists for similar behavior.
scss:
$list: 20px 30px 40px;
#mixin get-from-list($index) {
width: nth($list, $index);
}
$item-number: 2;
#smth {
#include get-from-list($item-number);
}
css generated:
#smth {
width: 30px;
}
http://sass-lang.com/docs/yardoc/file.SASS_REFERENCE.html#lists
http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#list-functions
Anytime I need to use a conditional value, I lean on functions. Here's a simple example.
$foo: 2em;
$bar: 1.5em;
#function foo-or-bar($value) {
#if $value == "foo" {
#return $foo;
}
#else {
#return $bar;
}
}
#mixin do-this($thing) {
width: foo-or-bar($thing);
}
Here's another option if you're working with rails, and possibly under other circumstances.
If you add .erb to the end of the file extension, Rails will process erb on the file before sending it to the SASS interpreter. This gives you a can chance to do what you want in Ruby.
For example: (File: foo.css.scss.erb)
// Set up variable and mixin
$foo-baz: 20px; // variable
<%
def do_this(bar)
"width: $foo-#{bar};"
end
%>
#target {
<%= do_this('baz') %>
}
Results in the following scss:
// Set up variable and mixin
$foo-baz: 20px; // variable
#target {
width: $foo-baz;
}
Which, of coarse, results in the following css:
#target {
width: 20px;
}
I came across the need to reference a colour dynamically recently.
I have a _colours.scss file for every project, where I define all my colours once and reference them as variables throughout.
In my _forms.scss file I wanted to setup button styles for each colour available. Usually a tedious task. This helped me to avoid having to write the same code for each different colour.
The only downside is that you have to list each colour name and value prior to writing the actual css.
// $red, $blue - variables defined in _colours.scss
$colours:
'red' $red,
'blue' $blue;
#each $name, $colour in $colours {
.button.has-#{$name}-background-color:hover {
background-color: lighten($colour, 15%);
}
}
I needed to use dynamic color values in sass variables.
After lots of search, I applied this solution:
In application.html.erb:
<style>
:root {
--primary-color: <%= current_client.header_color %>;
--body-color: <%= current_client.footer_color %>;
}
</style>
In variables.sass:
$primary: var(--primary-color);
And boom you are good to go!
Reference: https://medium.com/angular-in-depth/build-truly-dynamic-theme-with-css-variables-539516e95837
To make a dynamic variable is not possible in SASS as of now, since you will be adding/connecting another var that needs to be parsed once when you run the sass command.
As soon as the command runs, it will throw an error for Invalid CSS, since all your declared variables will follow hoisting.
Once run, you can't declare variables again on the fly
To know that I have understood this, kindly state if the following is correct:
you want to declare variables where the next part (word) is dynamic
something like
$list: 100 200 300;
#each $n in $list {
$font-$n: normal $n 12px/1 Arial;
}
// should result in something like
$font-100: normal 100 12px/1 Arial;
$font-200: normal 200 12px/1 Arial;
$font-300: normal 300 12px/1 Arial;
// So that we can use it as follows when needed
.span {
font: $font-200;
p {
font: $font-100
}
}
If this is what you want, I am afraid as of now, this is not allowed
I have a scss file with over 20 lines of color variables. I want to create a css file with these variables to have one class for color and class for background-color.
Example:
from scss variable
$color-red: #FF0000;
to css
.color-red { color:#FF0000; }
.bg-color-red { background-color:#FF0000; }
Is there any Gulp plugin that allows me to do it?
any recomendation accepted but i need to do it with gulp if it is possible.
As #chriskirknielsen suggested, sass maps and the #each rule is a good choice here. This is the first time I have used these concepts but this works in my testing.
Your colors.scss file would look like this:
$colors: ("color-red": "#FF0000", "color-green": "#00ff40"); // etc.
#each $color, $value in $colors {
.#{$color} {
color: #{$value};
}
.bg-#{$color} {
background-color: #{$value};
}
}
The gulp-sass output in colors.css is:
.color-red {
color: #FF0000; }
.bg-color-red {
background-color: #FF0000; }
.color-green {
color: #00ff40; }
.bg-color-green {
background-color: #00ff40; }
See https://sass-lang.com/documentation/values/maps#do-something-for-every-pair
I'm new with Sass stuff and I've been reading about different ways to use variables, this principle I'm trying to apply is just for colors, some of the solutions I've found were something like this (map-get):
$colors: (
lighestGray: #F8F8FA,
lightGray: #A5ACBA,
light: #FFFFFF,
dark: #000000,
link: #428bca,
linkHover: #555,
navBlue: #7AC243,
navGreen: #009CDC,
);
Then you use it on your class like this:
.my-class {
color: map-get($colors, dark);
}
And the other way is to use:
$color-black: #000000;
Then you use it like this:
.my-class {
color: $color-black;
}
My question is, which option is better? or map-getfunction has another purpose?, has Sass a pattern for this or it depends on each web-developer?.
Thanks for helping me out!.
Regards.
The differences is that when you use $map variables, they are best designed for using through iterations or using #each.
Sample case:
SCSS
// Map variable
$icons: (
facebook : "\f0c4",
twitter : "\f0c5",
googleplus : "\f0c6",
youtube : "\f0c7"
);
// Mixin doing the magic
#mixin icons-list($map) {
#each $icon-name, $icon in $map {
#if not map-has-key($map, $icon-name) {
#warn "'#{$icon-name}' is not a valid icon name";
}
#else {
&--#{$icon-name}::before {
content: $icon;
}
}
}
}
// How to use it
.social-link {
background-color: grey;
#include icons-list($icons);
}
CSS
// CSS Output
.social-link {
background-color: grey;
}
.social-link--facebook::before {
content: "";
}
.social-link--twitter::before {
content: "";
}
.social-link--googleplus::before {
content: "";
}
.social-link--youtube::before {
content: "";
}
This code was taken from my own answer in the following post but the answer is a case use of #each :)
Hope this help you
Example making a theme with css variables with fallback color
see codepen css variables
// VARS (FOR FALLBACK)
// -------------------
$theme-base: #70c1ac;
$theme-base-aa: adjust-color($theme-base, $blue: 125);
// PROCESSED THEME
$theme-color: $theme-base;
$theme-color-dark: darken($theme-color, 20%);
$theme-color-light: lighten($theme-color, 20%);
$theme-color-mixed: mix(#fff, $theme-color, 75%);
$theme-color-trans: transparentize($theme-color, .4);
// PROCESSED SECONDARY
$theme-color-aa: $theme-base-aa;
$theme-color-aa-dark: darken($theme-color-aa, 20%);
$theme-color-aa-light: lighten($theme-color-aa, 20%);
$theme-color-aa-mixed: mix(#fff, $theme-color-aa, 75%);
$theme-color-aa-trans: transparentize($theme-color-aa, .4);
$theme-colors: (
"aa-dark": $theme-color-aa-dark,
"aa-light": $theme-color-aa-light,
"aa-mixed": $theme-color-aa-mixed,
"aa-trans": $theme-color-aa-trans,
aa: $theme-color-aa,
dark: $theme-color-dark,
light: $theme-color-light,
mixed: $theme-color-mixed,
theme: $theme-color,
trans: $theme-color-trans,
);
#mixin themeColor ($prop, $color: null) {
#if ($color) {
#{$prop}: map-get($theme-colors, $color);
#{$prop}: var(--theme-color-#{$color})
} #else {
#{$prop}: map-get($theme-colors, theme);
#{$prop}: var(--theme-color);
}
}
#mixin setThemeColors($base1: "", $base2: "") {
// BASE THEME COLORS
$color-base: $theme-base;
$color-aa: $theme-base-aa;
#if ($base1) {
$color-base: $base1;
$color-aa: $base2;
}
// PROCESSED THEME COLORS
$color-aa-dark: darken($color-aa, 20%);
$color-aa-light: lighten($color-aa, 20%);
$color-aa-mixed: mix(#fff, $color-aa, 75%);
$color-aa-trans: transparentize($color-aa, .5);
$color-aa: $color-aa;
$color-dark: darken($color-base, 20%);
$color-light: lighten($color-base, 20%);
$color-mixed: mix(#fff, $color-base, 75%);
$color-trans: transparentize($color-base, .5);
// CSS VARIABLES
--theme-color-aa-dark: #{$color-aa-dark};
--theme-color-aa-light: #{$color-aa-light};
--theme-color-aa-trans: #{$color-aa-trans};
--theme-color-aa: #{$color-aa};
--theme-color-dark: #{$color-dark};
--theme-color-light: #{$color-light};
--theme-color-mixed: #{$color-mixed};
--theme-color-trans: #{$color-trans};
--theme-color: #{$color-base};
}
:root {
#include setThemeColors($theme-base, $theme-base-aa);
}
body {
#include themeColor("background","mixed");
font-size: 2rem;
}
ul {
list-style: none; /* Remove default bullets */
}
ul li::before {
content: "\2022"; /* Add content: \2022 is the CSS Code/unicode for a bullet */
#include themeColor("color","dark");
font-weight: bold; /* If you want it to be bold */
display: inline-block; /* Needed to add space between the bullet and the text */
width: 1.2em; /* Also needed for space (tweak if needed) */
margin-left: -.8em; /* Also needed for space (tweak if needed) */
}
li {
#include themeColor("color", "light");
#include themeColor("background", "aa-dark");
}
Why pick one when you can have them both.
_variables.scss
$color0 : white;
$color1 : red;
$color2 : green;
$color3 : blue;
_lists.scss
#use "variables";
#use "sass:map";
#use "sass:meta";
#use "sass:list";
#function dynamic($variable){
$i: 0;
$list: ();
#while(variable-exists($variable + $i)){
$list: list.append($list, map.get(meta.module-variables(variables), $variable + $i));
$i: $i + 1;
}
#return $list;
}
$colors: dynamic('color'); // white red green blue
Import both into your scss files and use the list when you need to loop and the variables for shorthand when applying styles.
map-get is used for getting css value from more kind of object.
suppose you have $param where you have defined multiple properties and now you want to assign. you can use it in following ways -
color: map-get($params, "color");
Where else simple variable holds only single value
map-get to get css value from object holding multiple values whereas
variable to hold single value
I have a variable which have empty string as default value and it can be changed dynamically based on skin name. So I tried to write my sass selector like this.
default.scss:
$skin: '';
green.scss:
$skin: 'green';
main.scss:
#import 'default.scss';
.#{$skin} .header{
color: black;
}
So I expected the below output from generated CSS.
.header{
color: black;
}
and
.green .header{
color: black;
}
But it throws below error while compiling
Invalid CSS after ".": expected class name, was ".header"
You could use a function for this:
$skin: 'green';
#function skin(){
#if $skin != '' { #return '.' + $skin + ' '; }
#else { #return ''; }
}
Now you could use it like this:
#{skin()} .header { ... }
Which will output:
.green .header { display: block; }
It might be better to use a better global variable name (skin seems like something that might quickly be reused - I would suggest something like $global-skin-name or something, but thats just semantics).