forms/src/plugins/plugin.js

// we need our modal component
import ModalDialog from './ModalDialog'

const Modal = {
	// every plugin for Vue.js needs install method
	// this method will run after Vue.use(<your-plugin-here>) is executed
	install(Vue, options) {
		// We must create new Eventbus
		// which is just another Vue instance that will be listening for and emiting events from our main instance
		// this EventBus will be available as Modal.EventBus
		this.EventBus = new Vue()

		// making our modal component global
		// eslint-disable-next-line vue/match-component-file-name
		Vue.component('ModalDialog', ModalDialog)

		// exposing global $modal object with method show()
		// method show() takes object params as argument
		// inside this object we can have modal title, text, styles... and also our callback confirm function
		Vue.prototype.$modal = {
			show(params) {
				// if we use this.$modal.show(params) inside our original Vue instance
				// we will emit 'show' event with parameters 'params'
				Modal.EventBus.$emit('show', params)
			},
		}
	},
}

export default Modal