When I listen to events within a view it gets triggered 3 times. Is there any way to prevent this? When I move the event listener to the Entry Point it triggers only once. But I need a way to tell the view that information has changed. At first I had something like the following in the view.

cart.on("afterAddLine", function() {
    // do something
});

Then I tried moving it to the entry point and it triggers once, but then I try to pass an event to the view and again it is triggered 3 times. In the Entry Point I have the following.

cart.on("afterAddLine", function() {
    Backbone.trigger("change:total_weight");
});

Then in the view I have the following.

Backbone.on("change:total_weight", function() {
    self.calculateTotalWeight();
});

Typically either with something like _.debounce(), a promise or some of sort global flag that gets set to true after the first call

I did try

Backbone.once

and it still triggers 3 times, but not

_.once()

.