Vue 2 and child component events with multiple components - events

Question

I've read this question / answer, and whilst that works when the parent contains a specific component, in my scenario the parent contains this:
<component :is="currentView"></component>
and the value of currentView determines which component is 'loaded' at any particular time. So, using v-on:event="handler" in the component tag here means all child components must use the same event name :(. Is it possible in the created() function of the parent to set up specific handlers which will be called regardless of which component is currently 'in view', and when they each might send different events? For example, I have a login component which sends a 'login' event, and a data view component which sends an 'update' event. In the parent, I want something like this:
this.$on('login', doLogin)
this.$on('update', doUpdate)
However, that's listening to events from itself, not its children. I also tried giving the component a ref:
<component ref="main" :is="currentView"></component>
and using this.$refs.main.$on('login', doLogin), but the $refs object isn't created until the initial render, so that can't go in the mounted() method (too early), and in the updated() method it will be repeatedly called which I'm sure isn't a good idea...

Answer 1

you could set a global event and then pass the name of the action as a part of the payload, i.e
const Login = {
template: `<h1>Login</h1>`,
mounted() {
this.$emit('global-event', {
action: 'login',
data: {
user: 'foo',
},
})
},
}
const Update = {
template: `<h1>Update</h1>`,
mounted() {
this.$emit('global-event', {
action: 'update',
data: {
user: 'foo bar',
},
})
},
}
new Vue({
el: '#app',
data: {
called: {
update: 0,
login: 0,
},
currentView: 'login',
},
components: {
Login,
Update,
},
methods: {
// within doSomething you would process the various events based on their payload.action
doSomething (payload) {
this.called[payload.action]++
},
toggleView () {
this.currentView = this.currentView === 'login' ? 'update' : 'login'
},
},
})
<script src="https://unpkg.com/vue/dist/vue.js"></script>
<div id="app">
<component #global-event="doSomething" :is="currentView"></component>
<button #click="toggleView">toggle view</button>
<pre>{{ called }}</pre>
</div>

Answer 2

Gah! After spending ages searching, finding nothing, then posting here, I of course immediately stumble on the answer.
But this only applies if you have control over the child components (I'm building all of them). In the child, you simply:
this.$parent.$emit('login', {some: 'data'})
And then set up the event listeners with this.$on('login', doLogin) in the parent as normal in the created() method.
I'm sure there will be a scenario where I'm using a third party component that simply calls this.$emit(), and at the moment, I can't see any alternative to v-on:eventName="handler" in the parent.