Setting Complex react inline styles such as hover, active on react components such as button

Question

I have the following styles in css for my buttons. I am also using bootstrap.

.btn-primary {     background-color: #229ac8;     background-image: linear-gradient(to bottom, #23a1d1, #1f90bb);     background-repeat: repeat-x;     border-color: #1f90bb #1f90bb #145e7a;     color: #ffffff;     text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.25); } .btn-primary:hover, .btn-primary:active, .btn-primary.active, .btn-primary.disabled, .btn-primary[disabled] {     background-color: #1f90bb;     background-position: 0 -15px; } 

I have defined a button as a component in react.

const MyButton = ({children, onClick, classNames, ...rest }) => (     <button         onClick   = {onClick}         className = {`${classNames}`}         {...rest}     >         {children}     </button> ); 

Based on some value fetched from the server I want to change the complete color of the button.

Question 1:

How can I set the button's complete style as inline style?

Question 2:

Also, can I use some scss features like mixins in react to generate button styles dynamically passing color as variable ?

Question 3:

Should I use inline styles or classnames using css in js?

For a generic component such as a button should we use a global class which can be reused in all places where button is defined or use a local inline style and create inline styles in all places?

Answer 1

CSS in JS (with pseudo classes & MQ support)

There are lots of libs to write CSS with React that supports pseudo classes but all, if not all of them requires you to inline or write your CSS in JS Which I highly recommend

CSS Modules (Write your CSS as normal, but in a better way)

There is also CSS modules which if you are already using Webpack should be simple to set it up, which let you import/require your CSS as an object use it your component like so:

import styles from './Button.css'  const MyButton = ({children, onClick, type='primary', ...rest }) => (     <button         onClick   = {onClick}         className = {styles.primary}         {...rest}     >         {children}     </button> ); 

Decoupling your components

I'd also add that you shouldn't pass classes to the <Button /> and deal with the conditions inside the component itself. For example using classnames lib you can do something like the following.

import classnames from 'classnames'  const MyButton = ({children, onClick, type='primary', ...rest }) => (     <button         onClick   = {onClick}         {/*            depends on the type prop, you will get the relevent button            so no need for consumers to care about the internals of the component         */}         className = {classnames('.btn', { [`btn-${type}`]: true })}         {...rest}     >         {children}     </button> ); 

You can even combine CSS Modules & classnames lib to create some powerful combinations.

Answer 2

Personally, I would use global CSS and wire it up with Webpack. It will keep your React much cleaner and of course more modular and easily edited.

To the best of my knowledge, SCSS features cannot be used inline with your React.

If you need to set inline styles in React it's done like this;

var buttonStyle = {     backgroundColor: "#229ac8",     backgroundImage: "linear-gradient(to bottom, #23a1d1, #1f90bb)",     backgroundRepeat: "repeat-x",     borderColor: "#1f90bb #1f90bb #145e7a",     color: "#ffffff",     textShadow: "0 -1px 0 rgba(0, 0, 0, 0.25)" } 

<button style={buttonStyle}>Button</button>