Is it possible to emit a custom event from the directive in the component to which this directive is attached.
I was expecting it to work as described in example, but it does not.
Example:
//Basic Directive
<script>
Vue.directive('foo', {
bind(el, binding, vnode) {
setTimeout(() => {
//vnode.context.$emit('bar'); <- this will trigger in parent
vnode.$emit('bar');
}, 3000);
}
});
</script>
//Basic Component
<template>
<button v-foo @bar="change">{{label}}</button>
</template>
<script>
export default{
data() {
return {
label: 'i dont work'
}
},
methods: {
change() {
this.label = 'I DO WORK!';
}
}
}
</script>
Any ideas on the matter? Am I missing something?
JSFiddle: https://jsfiddle.net/0aum3osq/4/
Update 1:
Okay, i've found that if I call vnode.data.on.bar.fn();
(or fns()
in latest Vue versions) in directive it will trigger bar
event handler.
Update 2:
Temporary solution:
/*temp. solution*/
var emit = (vnode, name, data) => {
var handlers = vnode.data.on;
if (handlers && handlers.hasOwnProperty(name)) {
var handler = handlers[name];
var fn = handler.fns || handler.fn;
if (typeof fn === 'function') {
fn(data);
}
}
}
//Basic Directive
<script>
Vue.directive('foo', {
bind(el, binding, vnode) {
setTimeout(() => {
emit(vnode, 'bar');
}, 3000);
}
});
</script>
So the solution I am using in Vue 2+ (considering there were no answers so far):
In directive add method:
var emit = (vnode, name, data) => {
var handlers = (vnode.data && vnode.data.on) ||
(vnode.componentOptions && vnode.componentOptions.listeners);
if (handlers && handlers[name]) {
handlers[name].fns(data);
}
}
And call it this way:
bind(el, binding, vnode) {
emit(vnode, 'bar' , {some: 'event', data: 'here'});
}
The benefits of an approach:
1 Keep the same code-style in your project, meaning that every handler can be declared as
v-on:handler_name
and be handled in meaningful (for developer) way. Other solutions, like sending callback as parameter, are sometimes confusing and not obvious without digging into documentation/code.
2 Using built-in events system also allows to gracefully handle event objects. For example, this code will work perfectly fine:
<button v-foo @bar="bar(1, $event, 2)">{{label}}</button>
...
methods: {
bar(one, event, two) { console.log(one, event, two); }
}
EDIT:
In v2.1+ you can use this inside directive binding:
vnode.context.$emit(eventname)