Style-builder

Style builder for React and React Native

Rationale

Style builder is a React plugin which makes it easy to do stateful styling of components. Styles are registered as functions, which depend on change to either state, props change or either. Whenever state or props change, the StyleBuilder is re-evaluated for the relevant style functions and the component is auto-matically re-rendered with the new (generated) style.

Example app

You can see a demo-app using style builder.

Getting Started

$ npm i -S style-builder

Usage

You can use StyleBuilder with React or React Native as shown below. Use StyleBuilder.create to creat a StyleBuilder class for your component with the styles map containing your styling functions (think "reactive style classes").

StyleBuilder.create(styleObj)

The styleObj can be either an Object or a class instance (via new).

React

import { StyleBuilder } from 'style-builder.js'

const TodoMixin = {
  title(state, props) {
    return {
      color: state.todo && state.todo.completed ? 'red' : 'green',
      backgroundColor: props.count > 1 ? 'yellow' : 'white'
    }
  },
  heading(state) {
    return {
      color: state.on ? 'blue' : 'gray',
    }
  }
};

export default StyleBuilder.create(TodoMixin, {
    name: 'MyComponent'
});

Using Style classes

As an alternative, pass a Style class and apply one or more class mixins to "mix and match" global and local styles if needed...

You can also use Object.assign or _.merge to merge objects directly.

import { mixin } from 'core-decorators';

@mixin(TodoMixin)
class Styles {
}

export default StyleBuilder.create(new Styles(), {name: 'App'});

Component usage

You currently need to use generators: @statefulStyling and @updateStyles

The @statefulStyling decorator adds the following functions to the component class:

• updateState
• initStyles
• updateStyles

The updateState function clears the "style cache key" before the state is set. Use updateState to set the state instead of setState for stateful styles to work correctly and avoid infinite recurssion! initStyles creates the initial StyleBuilder (in componentWillMount) and updateStyles is called by componentWillUpdate just before a new render to update the styling state.

Use the @updateStyles decorator on componentWillMount and componentWillUpdate. This ensures that the StyleBuilder is called whenever the component is about to render after a state/props change. It will then calculate the styles based on the new state/props and set it on local state. Styles are always local state (ie in local scope) of the component and should not be reflected in app state!

import Styler from './Styler.js'
import { statefulStyling, updateStyles } from 'style-builder'
import { injectProps } from 'relpers'

import React, {
  Component
} from 'react'

// use 'native' to use 'native' computer
@statefulStyling('browser', Styler)
export default class MyComponent extends Component {

  constructor(props) {
    super(props);
    this.state = {
      todo: {
        completed: false
      }
    }
  }

  @updateStyles
  componentWillMount() {
  }

  @updateStyles
  componentWillUpdate() {
  }

  _completed() {
    this.updateState({todo: {completed: true}});
  }

  _start() {
    this.updateState({todo: {completed: false}});
  }

  // https://github.com/goncalvesjoao/relpers
  @injectProps('state', 'props')
  render({ styles = {} }) {
    // console.log('render styles', styles);
    return (
      <div style={styles.header}>
        <div style={styles.title}>Blip</div>
        <button onClick={this._completed.bind(this)} >Complete</button>
        <button onClick={this._start.bind(this)} >Start</button>
      </div>
    )
  }
}

React Native

For React Native you need to register a special native computer, which wraps the built style result in a StyleSheet instance.

import { StyleBuilder } from 'style-builder.js'
import { StyleSheet } from 'react-native'

function native(state, props) {
    return StyleSheet.create(this.default())
}

export default StyleBuilder.create(TodoMixin, {
    name: 'MyComponent'
    computers: {
        native: native
    }
});

Development

Babel6 is used to compile into ES5.

npm compile

Testing

Mocha with chai is used for testing in /test

npm test

Contributing

Please submit all issues and pull requests to the kristianmandrup/style-builder repository!

Support

If you have any problem or suggestion please open an issue here.

License

The MIT License

Copyright (c) 2016, Kristian Mandrup

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.