Emit event from Directive to parent element

Question

I have an element in HTML template of an Angular 2 app. I add a directive to it:

<div myCustomDirective>HELLO</div> 

I want that whenever I hover over the div the text inside the div should be changed, but it needs to be done from Directive (mouseover) event.

How to emit an event from a Directive and capture it inside a parent element?

Answer 1

If myCustomDirective has an output @Output() someEvent:EventEmitter = new EventEmitter(); then you can use

<div myCustomDirective (someEvent)="callSomethingOnParent($event)">HELLO</div> 

Answer 2

I'd like to add to @GünterZöchbauer's answer that if you're trying to emit an event from a structural directive and using an asterisk (*) syntax when applying the directive, it won't work. Angular 5.2.6 still doesn't support @Output binding for structural directives if used with the * syntax (see GitHub issue).

You have to transform it to de-sugarized form (see here), i.e.:

<ng-template [customDirective]="foo" (customDirectiveEvent)="handler($event)">   <div class="name">{{hero.name}}</div> </ng-template> 

instead of:

<div *customDirective="foo" (customDirectiveEvent)="handler($event)" class="name">{{hero.name}}</div>