Watch Vue 3 global variable for changes

Question

I set a provider in my main.ts file:

app.provide('currentPage','test1')

And then inject it in a component Home.vue:

inject: ['currentPage'],

I then can update it and show it in that component without a problem using {{ currentPage }}.

But I want another component DeepNestedComponent.vue to be able to edit it, and Home.vue to be aware of the change.

When I inject the same provider in DeepNestedComponent.vue, I can edit and display in the component, but Home.vue is not aware of the change and {{ currentPage }} still display 'test1'.

How can I do that?

Answer 1

This pattern is designed only to pass some property from grandparent component to grandchild one, your case needs a shareable state based on Vuex or a composable function, let's build a solution based on the second approach :

define the composable function :

usePagination.ts

import {  ref } from "vue";

const currentPage=ref('test')

export default function usePagination(){

  function setCurrentPage(val:string){
      currentPage.value=val;
 }

return {currentPage, setCurrentPage}
}

DeepNestedComponent.vue

import usePagination from './usePagination'
...
setup(){
  const { setCurrentPage} =usePagination();

  // then use setCurrentPage to update the page

}

Home.vue :

import usePagination from './usePagination'
...
setup(){
  const { currentPage} =usePagination();

  // now you could receive the changes made in the other component.
  return {
       currentPage // expose it to the template 
   }
}