what is fourth item we are passing to js method?

Question

this is my code here:

handleKeyUpOnNewRecipient : function(component, event, helper, recipient){
    component.set("v.recipients", _.unionBy(component.get("v.recipients"), [recipient], 'id'));
    component.set("v.inputKeyword", '');
},

Call of this function from controller:

doInit : function(component, event, helper) {
    component.set("v.searchEmail", {
        onValueChange: helper.handleKeyUpOnNewRecipient,
        lookupAPI: component.get("c.searchEmail"),
        component: component, event: event, helper: helper
    })
},

I don't understand what the fourth 'recipient' is that we are passing to handleKeyUpOnNewRecipient which is a method in helper class. Could anyone tell me?

Answer 1

The method is a helper method, which means the parameters are set by the component calling the method. You should have a component somewhere that has an attribute like:

<aura:attribute name="searchEmail" type="Object" access="public" />

Which will then try to call the method as:

component.get("v.searchEmail").onValueChange(component, event, helper, recipient);

The specifics may differ somewhat, but I believe that finding v.searchEmail in your code base should find what the parameter is supposed to be.

We can't tell you much beyond that from the code you've provided here.