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Wrapping of *Bootstrap CSS* as Polymer web componentto be used as shared style in full ShadowDOM mode




[ This description is mirrored from at on 2019-05-22 ]

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granite-bootstrap is a wrapping of Bootstrap CSS as Polymer shared styles modules (i.e. inside <dom-module> tags).

This project replaces and updates polymer-bootstrap, that won't be updated anymore Hybrid Polymer element, 1.x-2.x ready

Doc & demo

Using granite-bootstrap modules

Using polymer style modules modules is a two-step process: you need to use ES6 module imports to import the module, and a <style> tag to include the styles in the correct place.

To use granite-bootstrap in an element:

1. Add the dependency

Add the dependency to the package.json of your application:

   "dependencies": {
     "polymer3-granite-bootstrap": "^4.0.0-polymer3"

And then recover them via bower install.

2. Import the granite-bootstrap module you want to use

Usually you will simply want to import granite-bootstrap.js (wrap around bootstrap.css) or granite-bootstrap-min.js (wrap around bootstrap.min.css).

Supossing you're using the standard folder locations for your components:

 import 'granite-bootstrap.js';

3. Inside your component, use granite-bootstrap as shared style

In your element's template you add the include for the granite-bootstrap module:

<style include="granite-bootstrap"></style>

A complete example

<!-- import the module  -->
 <script type="module">
    import 'granite-bootstrap.js';
<dom-module id="x-foo">
    <!-- include the style module by name -->
    <style include="granite-bootstrap"></style>
    <style>:host { display: block; }</style>
  <script>Polymer({is: 'x-foo'});</script>

Generating the style modules

To generate the style modules we use the granite-css-modularizer node script:

1. Clone the repository and recover the dependencies of granite-css-modularizer

Clone the granite-css-modularizer repository and recover the dependencies using yarn (or npm) :

$ yarn install
yarn install v1.2.1
info No lockfile found.
[1/4] Resolving packages...
[2/4] Fetching packages...
[3/4] Linking dependencies...
[4/4] Building fresh packages...
success Saved lockfile.
Done in 0.83s.

2. Recover Bootstrap

Recover Bootstrap distribution using yarn (or npm):

$ yarn add bootstrap@4.0.0-beta.2
yarn add v1.2.1
info No lockfile found.
[1/4] Resolving packages...
[2/4] Fetching packages...
[3/4] Linking dependencies...
warning "bootstrap@4.0.0-beta.2" has unmet peer dependency "jquery@1.9.1 - 3".
warning "bootstrap@4.0.0-beta.2" has unmet peer dependency "popper.js@^1.12.3".
[4/4] Building fresh packages...
success Saved lockfile.
success Saved 1 new dependency.
└─ bootstrap@4.0.0-beta.2
Done in 0.55s.

Currently granite-bootstrap uses Bootstrap version 4.0.0-beta.2, if you need another version you can change simply install it.

3. Generate the components

Using NodeJS and the granite-css-modularizer.js to transform Bootstrap CSS files into polymer elements.

$ node ../granite-css-modularizer.js ./node_modules/bootstrap/dist/css ./css_modules/granite-bootstrap

After executing it, a series of HTML files is generated in the ./css_modules/granite-bootstrap folder, each one corresponding to a Bootstrap CSS file.

$ ls ./css_modules/granite-bootstrap/*.html
granite-bootstrap-grid.html  granite-bootstrap-grid-min.html  granite-bootstrap.html  granite-bootstrap-min.html  granite-bootstrap-reboot.html  granite-bootstrap-reboot-min.html


  1. Fork it!
  2. Create your feature branch: git checkout -b my-new-feature
  3. Commit your changes: git commit -m 'Add some feature'
  4. Push to the branch: git push origin my-new-feature
  5. Submit a pull request :D

Install dependencies and run the demo

  • Run npm install from the repo directory:

     npm install
  • Run the Polymer development server from the root project directory:

    polymer serve --open

Note on semver versioning

I'm aligning the versions of this element with Bootstrap version, in order to make easier to choose the right version


Apache 2.0


(Loading compatibility data...)

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  • @polymer/polymer#3.3.0
MIT License


Polymer 3.0+
Polymer 2.0+ in 4.0.0-0
Browser Independent