controllerim

Controllerim

A simple, clean and well structured state management library for react

Installation

npm install controllerim --save

Migrating from Controllerim v2 to v3

The migration process should be very easy. Follow the docs and the example project for understanding the new API.

Basic usage example

Inside ParentController.js:

import { controller } from 'controllerim';

class _ParentController {
  constructor() {
    this.state = {
      message: 'hello' 
    };
  }
  getMessage() {
    return this.state.message;
  }
  setMessage(value) {
    this.state.message = value;
  }
}

export const ParentController = controller(_ParentController);

Inside Parent.jsx:

import React, { Component } from 'react';
import { observer } from 'controllerim';
import { ParentController } from './ParentController';

class Parent extends Component {
  constructor(props) {
    super(props);
    this.controller = ComponentController.create(); //returns a fresh controller instance
  }

  render() {
    return (
      <div>
        <h1>{this.controller.getMessage()}</h1>
        <Child/>
        <button onClick={() => this.controller.setMessage('hello world!')}>Click me to change message</button>
      </div>
    );
  }
};

export default observer(Parent);

Inside Child.jsx:

import React, { Component } from 'react';
import { observer} from 'controllerim';
import {ParentController} from './ParentController'

class Child extends Component {
  constructor(props){
    super(props);
    this.parentController = ParentController.getInstance(); //returns an existing instance of the parentController. You could supply an id if you you have more than one instances of the parent controller.
  }
 
  render() {
    return (
      <div>
        <span>This is a message from parent: {this.parentController.getMessage()}</span>
      </div>
    );
  }
};

export default observer(Child);

Example project

Here is a Simple example project You can see the source code under the example folder: demo-app/src If you want to run it locally: After cloning the repository, navigate to the demo-app folder and type in your terminal:

npm install
npm start

How

Controllerim utilizes Mobx behind the scenes. You don't need to learn Mobx in order to use Controllerim, but a basic understanding of Mobx is recommended.

Api

controller(controllerClass)

Arguments:

• controllerClass: any es6 class with a state member.

Returns:

• Object: { create(), getInstance() }: an object with two factory methods for getting a new controller instance

A controller is a plain Javascript class that holds a state and methods for manipulating the state. All the methods of the controller are smartly memoized and computed, thus if you do some heavy calculation, it will be re-calculated when really needed.

The observers (React Components that you wrapped within observer) will react to any change in the state, even changes of deep nested properties.

create(id?: string (default: 'globalInstance') ):

Returns a new instance of the given controller. You should use this method when you know for sure that you need a fresh instance and not an existing one (most of the time you should prefer create over getInstance). You can pass an id, for being used later by getInstance.

getInstance(id?: string (default: 'globalInstance')):

Returns an existing instance of the given controller, or a new one if there isn't any existing instance yet. If you don't supply an id, the return value will be the default global instance.

controller Usage example:

import {controller} from 'controllerim';

class _AppController {
  constructor() {
    this.state = {totalNotesCount: 2};                                 
  }

  getTotalNotesCount() {
    return this.state.totalNotesCount;
  }

  increaseCounter() {
    this.state.totalNotesCount++;
  }
}

export const AppController = controller(_AppController);

Your React component will create an instance of the controller like this:

import {AppController} from 'controllerim';

class App extends React.Component {
  constructor(props) {
    super(props);
    this.controller = AppController.create();
  }

  render(){
    <div>
      <div>{this.controller.getTotalNotesCount()}</div>
      <div onPress={() => this.controller.increaseCounter()}>click me</div>
    </div>
  }
}

useController(controllerInstance)

Allows you to use controller inside a functional component. Note that you still have to wrap your functional component within observer.

import React from 'react';
import {observer, useController} from 'controllerim';
import {FunctionalComponentController} from './TestComponentController';

export const FunctionalComponent = observer(() => {
  const controller = useController(FunctionalComponentController.create());
  return (
    <div>
      <div>{controller.getUserName()}</div>
      <div onClick={() => controller.changeUserName()}>click me</div>
    </div>
  );
});

observer(ReactComponent)

To become reactive, every React component that uses a controller, should be wrapped within observer.

import {observer} from 'controllerim';

export const SomeSmartComponent = observer(class extends React.Component {
...
})

store(storeClass)

A store is just a global singleton controller that is not conceptually bound to any specific component.

inside AppStore.js:

  import {store} from 'controllerim';

  class _AppStore {
    constructor(){
      this.state = {useName: 'bla'};
    }

    getUserName() {
      return this.state.userName;
    }
  }

  export const AppStore = store(_AppStore);

Inside component.jsx:

import React from 'react';
import {observer} from 'controllerim'
import {AppStore} from './AppStore';

class SomeComponent extends React.Component {
  render(){
    <div>{AppStore.getUserName()}</div> // <== The component will re-render on any change in getUserName
  }
}

export default observer(SomeComponent);