flake-determined
This is a different implementation of @sightread/flake. In this library, classNames are determinstic (hashes the class definition), and you will insert the css to be added yourself. This often has better results with SSG and SSR, and gives you more control.
A minimalist css in javascript renderer. Our mission is to be as small as possible while supporting all of the important use cases.
Features
- media queries
- pseudo-classes/pseudo-selectors
- your favorite css properties
- SSR
- no dependencies
- written in typescript
Installation
$ npm i @sightread/flake-determined
or
$ yarn add @sightread/flake-determined
Usage
import { css } from "@sightread/flake-determined";
const flake = css({
...
},
// optional second arg (default true) for caching classes
true | false | undefined
)
calling css
function returns an object:
{
// key, value mapping with [your key]: class name string
classes : { ... },
// the css string compiled from the css definitions
append: "",
// a hash key that corresponds to the append css string.
id: ""
}
Example:
import { css } from "@sightread/flake-determined";
const flake = css({
headerItem: {
color: "blue",
fontSize: "24px",
},
});
function MyComponent() {
// ... react stuff
return (
<div>
<h1 className={flake.classes.headerItem}>It works!</h1>
{flake.append && <style>{flake.append}</style>}
</div>
);
}
css
function returns the classes as well as the css string to insert yourself. Since the classes are deterministic, multiple instances of a component will only return the append string once. After the first addition of a component, append will be an empty string. Also individual class definitions are cached so multiple calls to css
with the same definitions will not return css.
This is done by creating a hash for each class definition. If this hash key has been seen before, the css string does not have to be added again.
Example:
import { css } from "@sightread/flake-determined";
const flake = css({
button: {
backgroundColor: "white"
border: "1px solid lightgrey",
borderRadius: 5,
fontSize: 15,
},
header: {
color: "blue",
fontSize: "24px",
},
});
function MyComponent1() {
// ... react stuff
return (
<div>
<style>{flake.append}</style>
<h1 className={flake.classes.header}>It works!</h1>
<button className={flake.classes.button}>Click me</button>
{/* or:
{flake.append && <style>{flake.append}</style>}
*/}
</div>
);
}
/* since the definition of
header: {
color: "blue",
fontSize: "24px"
}
has been seen before, this call to css will
return {
...
classes: {
header: "header-[hash]"
}
append: "",
id: 0,
}
*/
const flake2 = css({
header: {
color: "blue",
fontSize: "24px",
},
})
function OtherHeader() {
return (
<>
{flake.append && <style>{flake.append}</style>}
<h2 className={flake.classes.header}>It works too!</h2>
</>
)
}
function App() {
return (
<div>
<MyComponent1/>
<OtherHeader/>
</div>)
}
Turn off caching
If you would like to tell flake to always return a full append
string, pass false
as a second argument to css
.
With nextjs
A convenient way to return style tags in the dom is to use Head
with the flake id as the key.
import Head from "next/head"
// same as previous example
function MyComponent() {
return (
<div>
{/* same as previous example */}
<Head>
<style key={flake.id}>{flake.append}</style>
</Head>
</div>
);
Peudoclasses
const flake = css({
navLink: {
color: "blue",
"&:hover": {
color: "black",
textDecoration: "underline"
},
"&:focus": {
color: "black"
}
}
},
})
Selectors
const flake = css({
container: {
'& p:nth-child(odd)': {
fontSize: 18,
color: 'lightgrey',
transition: '300ms',
},
}
})
...
...
<div className={flake.classes.container}>
<p>paragraph one</p>
<p>paragraph two</p>
<p>paragraph three</p>
<p>paragraph four</p>
</div>
Media Queries
We provide a small api for media queries for classes. The following example is equivalent to:
@media only screen and (min-width: 900px) {
.container {
width: 50%;
}
}
@media only screen and (max-width: 900px) {
.container {
width: 100%;
}
}
import { mediaQuery } from "@sightread/flake-determined";
const flake = css({
container: {
[mediaQuery.up(900)]: {
width: "50%",
},
[mediaQuery.down(900)]: {
width: "100%",
},
},
});
Combining multiple classes
Often you may want to use multiple defined classes for one element, or conditionally use classes.
For either of these, use our classNames
function.
classNames
takes a variable number of arguments of either type string or object.
If the argument is a string, it will be concatonated the the return string.
If the parameter is an object, the associated keys of truthy values will be added.
In the example bellow, the button will have the classes associated with button
and
btnPrimary
while error
is false
, else button
and btnDisabled
.
import { classNames } from "@sightread/flake-determined";
const classes = css({
button: {
padding: "5px 10px",
fontSize: "16px",
color: "white",
},
btnPrimary: {
backgroundColor: "blue",
},
btnDisabled: {
backgroundColor: "red",
},
});
function MyComponent() {
const [error, setError] = useState(false);
// .. react stuff..
return (
<div>
...
<button
className={classNames(classes.button, {
[classes.btnPrimary]: !error,
[classes.btnDisabled]: error,
})}
>
Submit
</button>
</div>
);
}
License
MIT