How do I identify which widget emits or broadcasts an event in the Service Portal?

[nyancer3]

I've seen some very good content on using events to communicate between widgets (for example this post). However, I don't see how to identify the widget that is emitting or broadcasting the event.

Here is the scenario. I want to be able to dynamically embed catalog item widgets based on some user input (press a button, select it from a list of items, whatever). When the user selects the item, it gets added to an array and there is a widget embedded for each item in the array. What I would like to be able to do is to close the embedded widget once the catalog item has been submitted. The default cat item widget emits the event "$sp.sc_cat_item.submitted," but as far as I can tell there is no way to identify the widget that fired the event. If I can identify the widget, then I can remove it from the array.

[dvp]

Not sure if this is helpful..

$emit dispatches an event upwards ... $broadcast dispatches an event downwards

Detailed explanation
$rootScope.$emit only lets other $rootScope listeners catch it. This is good when you don't want every $scope to get it. Mostly a high level communication. Think of it as adults talking to each other in a room so the kids can't hear them.
$rootScope.$broadcast is a method that lets pretty much everything hear it. This would be the equivalent of parents yelling that dinner is ready so everyone in the house hears it.
$scope.$emit is when you want that $scope and all its parents and $rootScope to hear the event. This is a child whining to their parents at home (but not at a grocery store where other kids can hear).
$scope.$broadcast is for the $scope itself and its children. This is a child whispering to its stuffed animals so their parents can't hear.

[nyancer3 · Accepted solution]

Thanks for sharing this info. I already understand how $emit and $broadcast work, and also how they behave when called from $scope versus $rootScope. The issue I am running into is identifying which item fired the event.

I spent some additional time on this and was able to come up with a solution. In this case, I have an array of objects returned by spUtil.get() that I feed into the sp-widget directive. I made a copy of the widget-sc-cat-item widget so that I could add a parameter to the emitted event. I'm not sure if there is a more efficient way to do this, but I ended up sending c.widget with the event. Then, in the widget that embeds the cat item widget, I listen for the event and then loop through the widget item array, using angular.equals to do a deep compare on the widget objects. When I tested this, it worked as I expected and I was able to automatically close the catalog item widget that had already been ordered.