Sometime you need to work with a kind of global state management throughout your Vue.js app to share data across components without the use of a state manager like Vuex, for any reasons, or just for the sake of simplicity...

In that prospect, we can create a simple store mechanism based on the instantiation of one ES6 class shared by components. Let's demonstrate how to quickly achieve this !

For this example, we're going to build a simple counter where we use components to increment - decrement - restore and return its value.

src/store/index.js

class Store {

    // constructor(...)
    // identifies the signature of Store(...) function
    constructor(){
        this.state = {
            count: 0
        }
    }

    // methods
    increment(){ this.state.count++ }

    decrement(){ this.state.count-- }

    restore(){ this.state.count = 0 }

}

// export new class instance
export default new Store()

We can now import our class instance in our components and access the count property of our state object with the 3 methods we have declared.

src/components/DecrementBtn.vue

  <template>
      <div class="card">
          <h2>Child Component #2</h2>
          <button @click="decrement">Decrement state.count</button>
      </div>
  </template>

  <script>
  // import store instance
  import Store from '../store'

      export default {
          methods: {
              decrement: () => Store.decrement()
          }
      }
  </script>

  //...

We create a button component DecrementBtn.vue and we bind an event listener to decrease the count value in the store when the button is clicked. We also store the Store.decrement() function call as a property of the methods object to make it available in our template.

Now that we have the idea, we can create the IncrementBtn.vue and RestoreBtn.vue components using Store.increment() and Store.restore() in the methods...

If you want to try this example yourself, I've compiled for you in this CodeSandbox, go check it out!

https://codesandbox.io/s/381mnn8oq5

# install dependencies
npm install

# serve with hot reload at localhost:8080
npm run dev

# build for production with minification
npm run build

For detailed explanation on how things work, consult the docs for vue-loader.