Angular 组件的全局 scss 变量，无需每次都导入它们

Question

I do already have SCSS variables defined in src/styles/settings/_variables.scss and I am importing them into src/styles.scss , but still these variables aren't available for every single component.

Is there any way to make a global file which holds all SCSS variables for the rest of my components? Because writing @import in every single component .scss file it is very frustrating, especially if I have many nested components.

I know, there is a lot of similar questions, but it seems like they're all outdated and do not relate to the recent versions of Angular.

I use Angular 7.3 with CLI.

Answer 1

You just need to add a little more config, so where you are declaring your global variables, you need to wrap it up in :root{} . So in src/styles/settings/_variables.scss .

:root 
{
--blue: #00b; // or any global you wish to share with components 
}

Then when you use them in the SCSS you will need to access them like so.

.example-class {
  background-color: var(--blue)
}

To add to this regarding comments, this method can use mixins , @media and keyframes and is not limited to just colours / font. That was an example.

From my understanding you need a global file src/assets/style/global and then to import each scss file into there where you are defining them like so.

@import 'filename';

If you dont want global variables to be used in within a component look when you have the globals working. Look into ViewEncapsulation , as this can be used to ignore them.

Answer 2

Is there any ways to make global file with scss variables available for all components?

Without importing global file everytime in each component, you want those sass variables been available, it's not possible.

The way it works in SASS , if using partials to better organize code, you can apply @import directive for referencing. So if there're some sass variables in shared/_variables.scss :

$lightslategray: #778899;
$darkgray: #A9A9A9;

and these variables need to be used in another stylesheet, stylesheet with them must be @import-ed into it firstly:

// Shared
@import "shared/variables";

.content {
  background: $lightslategray;
}

In Angular it works in a similar way (related referencing external stylesheet). So if you need some sass variables, mixins or functions to be used by a particular component.scss , there is no other clean way, but to reference them in that component.scss using @import directive. To ease the task, you can create a file src/_variables.scss and use syntax like this in your component.scss :

@import “~variables.scss”;

Answer 3

Easily possibe to access sass style(s) from a global file with two steps.

1. Add folder path of the style files to includePaths array in angular.json file.
2. Import style file by file-name in any component.

let say your files and folder structures is as follows: src > my-styles-folder > var.scss

angular.json

"architect": {
  "build": {
    ...
    "options": {
      "stylePreprocessorOptions": {
        "includePaths": [
          "src/my-styles-folder" // add path only, do not include file name
        ]
      },
      "styles": [
        ...
      ]
    }
    ...
  }
}

some-component.scss

@import "var"; // var.scss

mat-toolbar {
  height: $toolbar-height;
}

Answer 4

step one : go to custom scss file (shared/css/_variable.scss) and write this part

 :root{ --color-text: red; --color-btn-success: green; }

after go to style.scss (this is main file) and import this file :

 @import './shared/css/Variables';

now you can use variables in all components with this Syntax:

 .sample{ color : var(--color-text); }

Answer 5

In angular 8 work for me.

In your _variable.scss file you have to add:

:root{--my-var:#fabada}

After that go in your angular.json and add this in "styles":

{"input":"yourPath/_variables.scss"}

Answer 6

TL;DR

No, there is no better way in Angular and there will be no more convenient way to solve your problem.

More detailed answer

If I understood you correctly, you're messing up with all these dependency injection, for instance @import a specific SCSS holding your variables. So, your question is:

Is this a bug or a feature?

And, I have to say, it's a feature. This makes your components more flexible and the payoff is, that you have to care about these dependencies, but in the long run your code will be easier to maintain and will be more structured. Dependency is a core feature of modern JavaScript programming. So, if you like, you can stick to more old-fashioned style of programming, putting everything you need for your application into one single file. This is more kind of rethorical question.

If you look for instance to the „React world“, you will find even more necessity of structuring your injections. You do not just import a whole file and serve all variables, methods, classes etc. to your target component, instead you choose each single variable, each single method, which you'd like to use in your target component. This increases the effort of planning and structuring your whole application, but keep in mind the long run. Programming good maintainable software has more in common with a marathon than a sprint.

I'd like to share with you this Wikipedia article about „Dependency Injection“ . Maybe you'll find your answers there.

Motivation

To prevent you from leaving you with bad feelings, here is a wonderful saying of HL Mencken :

„For every complex problem there is an answer that is clear, simple, and wrong.“