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Call a Vue.js component method from outside the component

Let's say I have a main Vue instance that has child components. Is there a way of calling a method belonging to one of these components from outside the Vue instance entirely?

Here is an example:

var vm = new Vue({ el: '#app', components: { 'my-component': { template: '#my-template', data: function() { return { count: 1, }; }, methods: { increaseCount: function() { this.count++; } } }, } }); $('#external-button').click(function() { vm['my-component'].increaseCount(); // This doesn't work });


So when I click the internal button, the increaseCount() method is bound to its click event so it gets called. There is no way to bind the event to the external button, whose click event I am listening for with jQuery, so I'll need some other way to call increaseCount.

EDIT

It seems this works:

vm.$children[0].increaseCount();

However, this is not a good solution because I am referencing the component by its index in the children array, and with many components this is unlikely to stay constant and the code is less readable.

I added an answer using mxins if you want to give it a try. In my opinion I prefer to setup the app this way.
Why do you need to do that? I mean why do you need to call that method? Maybe better to use something like v-model?

t
tony19

In the end I opted for using Vue's ref directive. This allows a component to be referenced from the parent for direct access.

E.g.

Have a compenent registered on my parent instance:

var vm = new Vue({
    el: '#app',
    components: { 'my-component': myComponent }
});

Render the component in template/html with a reference:

<my-component ref="foo"></my-component>

Now, elsewhere I can access the component externally

<script>
vm.$refs.foo.doSomething(); //assuming my component has a doSomething() method
</script>

See this fiddle for an example: https://jsfiddle.net/xmqgnbu3/1/

(old example using Vue 1: https://jsfiddle.net/6v7y6msr/)

Edit for Vue3 - Composition API

The child-component has to return the function in setup you want to use in the parent-component otherwise the function is not available to the parent.

Note: doc is not affacted, because it provides all the functions and variables to the template by default.


That's because you probably haven't defined it. Look at the linked fiddle.
If you are using webpack then you won't be able to access vm due to the way it scopes modules. You can do something like window.app = vm in your main.js. Source: forum.vuejs.org/t/how-to-access-vue-from-chrome-console/3606
There's so official definition of what's a hack vs what's "normal" coding, but rather than call this approach a hack (or look for a "less-hacky" way of achieving the same thing) it's probably better to question why you need to do this. In many cases it might be more elegant to use Vue's event system to trigger external component behaviour, or even ask why you're triggering components externally at all.
This can come up if you are trying to integrate a view component into an already existing page. Rather than redesigning the page entirely, it is nice sometimes to incrementally add additional functionality.
I had to use this. : this.$refs.foo.doSomething();
J
Jesse Reza Khorasanee

You can set ref for child components then in parent can call via $refs:

Add ref to child component:

<my-component ref="childref"></my-component>

Add click event to parent:

<button id="external-button" @click="$refs.childref.increaseCount()">External Button</button>

var vm = new Vue({ el: '#app', components: { 'my-component': { template: '#my-template', data: function() { return { count: 1, }; }, methods: { increaseCount: function() { this.count++; } } }, } });


the cleanest solution so far.
Great answer. I'm just going to edit the html to be a bit smaller vertically. Currently I can only see 'Internal Button' when I run it which was can be confusing.
You can access from the parent component a ref using this : this.$refs.childref, used this to make a generic alert component for example
t
tony19

For Vue2 this applies:

var bus = new Vue()

// in component A's method

bus.$emit('id-selected', 1)

// in component B's created hook

bus.$on('id-selected', function (id) {

  // ...
})

See here for the Vue docs. And here is more detail on how to set up this event bus exactly.

If you'd like more info on when to use properties, events and/ or centralized state management see this article.

See below comment of Thomas regarding Vue 3.


Short and sweet! If you dislike the global bus variable, you can go a step further and inject the bus into your component using props. I'm relatively new to vue so I can't assure you that this is idiomatic.
new Vue() is deprecated in vue 3 for alternative follow this question
Event bus is not recommended patter (at least in vue 2/3), that is why it has been removed from docs. for more information you can read this or the same on from image here - the answer was provided by skirtle (moderator, MVP on Vue's the discord chennel). "References to event buses were removed from the Vue 2 docs a long time ago and we recently added something to the Vue 3 docs to actively discourage it"
H
Helder Lucas

You can use Vue event system

vm.$broadcast('event-name', args)

and

 vm.$on('event-name', function())

Here is the fiddle: http://jsfiddle.net/hfalucas/wc1gg5v4/59/


@GusDeCooL the example has been edited. Not that after Vuejs 2.0 some methods used there have been deprecated
Works well if there is only 1 instance of component, but if there are many instances, works better use $refs.component.method()
u
urig

A slightly different (simpler) version of the accepted answer:

Have a component registered on the parent instance:

export default {
    components: { 'my-component': myComponent }
}

Render the component in template/html with a reference:

<my-component ref="foo"></my-component>

Access the component method:

<script>
    this.$refs.foo.doSomething();
</script>

R
Roland

Say you have a child_method() in the child component:

export default {
    methods: {
        child_method () {
            console.log('I got clicked')
        }
    }
}

Now you want to execute the child_method from parent component:

<template>
    <div>
        <button @click="exec">Execute child component</button>
        <child-cmp ref="child"></child_cmp> <!-- note the ref="child" here -->
    </div>
</template>

export default {
    methods: {
        exec () { //accessing the child component instance through $refs
            this.$refs.child.child_method() //execute the method belongs to the child component
        }
    }
}

If you want to execute a parent component method from child component:

this.$parent.name_of_method()

NOTE: It is not recommended to access the child and parent component like this.

Instead as best practice use Props & Events for parent-child communication.

If you want communication between components surely use vuex or event bus

Please read this very helpful article


Yes, you can, but not considered 'best practice': downward to Child use properties, upward to Parent use events. To also cover 'sidewards', use custom events, or e.g. vuex. See this nice article for more info.
Yes it is not recommended to do so.
D
Dotnetgang

This is a simple way to access a component's methods from other component

// This is external shared (reusable) component, so you can call its methods from other components

export default {
   name: 'SharedBase',
   methods: {
      fetchLocalData: function(module, page){
          // .....fetches some data
          return { jsonData }
      }
   }
}

// This is your component where you can call SharedBased component's method(s)
import SharedBase from '[your path to component]';
var sections = [];

export default {
   name: 'History',
   created: function(){
       this.sections = SharedBase.methods['fetchLocalData']('intro', 'history');
   }
}

N
Nick Web

Here is a simple one

this.$children[indexOfComponent].childsMethodName();

S
Sarvar N

Using Vue 3:

const app = createApp({})

// register an options object
app.component('my-component', {
  /* ... */
})

....

// retrieve a registered component
const MyComponent = app.component('my-component')

MyComponent.methods.greet();

https://v3.vuejs.org/api/application-api.html#component


g
greybeard

I am not sure is it the right way but this one works for me. First import the component which contains the method you want to call in your component

import myComponent from './MyComponent'

and then call any method of MyCompenent

myComponent.methods.doSomething()

this doesn't give you access to any data in your component. if your doSomething is using any thing from data, this method is useless.
@cyboashu you are right but it is a perfect idea for me since I wanted to use generic methods from a mixin.
n
norbekoff

Declare your function in a component like this:

export default {
  mounted () {
    this.$root.$on('component1', () => {
      // do your logic here :D
    });
  }
};

and call it from any page like this:

this.$root.$emit("component1");

O
ODaniel

Sometimes you want to keep these things contained within your component. Depending on DOM state (the elements you're listening on must exist in DOM when your Vue component is instantiated), you can listen to events on elements outside of your component from within your Vue component. Let's say there is an element outside of your component, and when the user clicks it, you want your component to respond.

In html you have:

<a href="#" id="outsideLink">Launch the component</a>
...
<my-component></my-component>

In your Vue component:

    methods() {
      doSomething() {
        // do something
      }
    },
    created() {
       document.getElementById('outsideLink').addEventListener('click', evt => 
       {
          this.doSomething();
       });
    }
    

This isn't a VueJS style solution. It bypasses the VueJS component system.
d
dotNET

If you're using Vue 3 with <script setup> sugar, note that internal bindings of a component are closed (not visible from outside the component) and you must use defineExpose(see docs) to make them visible from outside. Something like this:

<script setup lang="ts">
const method1 = () => { ... };
const method2 = () => { ... };

defineExpose({
  method1,
  method2,
});
</script>

G
Gorbas

I have used a very simple solution. I have included a HTML element, that calls the method, in my Vue Component that I select, using Vanilla JS, and I trigger click!

In the Vue Component, I have included something like the following:

<span data-id="btnReload" @click="fetchTaskList()"><i class="fa fa-refresh"></i></span>

That I use using Vanilla JS:

const btnReload = document.querySelector('[data-id="btnReload"]');
btnReload.click();                

This is not considered good practice at all within vue, especially in the context of OP's question.