Wijmo and Sass
We recently switched to Sass to make it easier to create and maintain Wijmo CSS files.
Sass improves CSS the same way TypeScript improves JavaScript. It provides modularization, variables, structure, compile time syntax checking, selector nesting, functions, and more. Over the last few years, Sass has become the most popular CSS preprocessor, being supported by all popular JavaScript frameworks and bundler tools.
Just like TypeScript, Sass is optional. You can use the CSS files we build with Sass and forget it exists. But if you want to customize the Wijmo styles, create your own themes, or create smaller CSS files that include only the Wijmo modules you use, then we suggest you use Sass.
If you choose to use Sass, you will a Sass tool. Our favorites are:
Folder Structure
We use the following folder structure for Wijmo's Sass files:
wijmo.scss // main scss file
misc
_constants.scss // color names
_glyphs.scss // Wijmo glyphs
_mixins.scss // utility functions
_variables.scss // theme variables
core // modules in Wijmo core
_chart.scss
_chart_hierarchical.scss
_chart_interaction.scss
_core.scss
_gauge.scss
_grid.scss
_grid_filter.scss
_grid_grouppanel.scss
_input.scss
_nav.scss
enterprise // modules in Wijmo enterprise
_chart_finance.scss
_multirow.scss
_olap.scss
_sheet.scss
_viewer.scss
themes // bundled themes
wijmo.theme.cerulean.scss
wijmo.theme.cleandark.scss
wijmo.theme.cleanlight.scss
// etc
Following Sass conventions, files with names that start with an underscore are included by other files and do not generate stand-alone CSS files.
The wijmo.scss file is used to generate our main CSS file, wijmo.css. It contains the following:
// wijmo.scss
// misc
@import "misc/mixins"; // functions
@import "misc/constants"; // named colors
@import "misc/variables"; // theme variables
@import "misc/glyphs"; // wijmo glyphs
// core modules
@import "core/core";
@import "core/input";
@import "core/grid";
@import "core/grid_grouppanel";
@import "core/grid_filter";
@import "core/chart";
@import "core/chart_interaction";
@import "core/chart_hierarchical";
@import "core/gauge";
@import "core/nav";
// enterprise modules
@import "enterprise/sheet";
@import "enterprise/multirow";
@import "enterprise/olap";
@import "enterprise/viewer";
@import "enterprise/chart_finance";
If you run this through the Web Compiler or any other Sass tool, you will get the regular wijmo.css and wijmo.min.css output.
Smaller CSS files
If you don't use any of the Wijmo enterprise modules and would like to reduce the size of your CSS files, you could create a wijmo-core.scss file that looks like the wijmo.scss above minus the last five lines (the ones that include the enterprise modules).
This will create a wijmo-core.css file that is about half the size of the full wijmo.css.
We have done this for you already. The wijmo-core.css file is included in our distribution. But you can use this approach to generate optimized CSS files that include only the modules your application needs. For example, you could create a CSS file that contains rules only for the input and grid modules.
Custom Themes
In addition to the standard wijmo.css file, Wijmo includes many custom themes. Most themes are created by overriding the value of a few Sass variables. For example, the cerulean theme is created from the wijmo.theme.cerulean.scss file:
// wijmo.theme.cerulean.scss -- cerulean theme
$wj-bkg: #fcfcfc;
$wj-txt: #082d43;
$wj-bdr: none;
$wj-hdr-bkg: #033c73;
$wj-hdr-txt: #fff;
$wj-sel-bkg: #2a9fd6;
$wj-msel-bkg: #77afc9;
$wj-cell-grp-bkg: #777777;
//� etc �
@import "../wijmo.scss";
The theme file sets some Wijmo variables and then includes the base wijmo.scss file. That's all there is to it. The output is a wijmo.theme.cerulean.css file that can be used instead of the standard wijmo.css.
NOTE: The theme files are self-contained. They replace rather than extend the standard wijmo.css file. This is a change from previous versions of Wijmo.