Call another method from a method in same Lightning controller

Question

Given two controller methods defined for a Lightning component as follows, how can I call bar() from foo()? If I try it using the code shown below, I get the error, "bar is not defined".

({
    bar : function(component, event, helper) {
        console.log('bar just happened');
    },
    foo : function(component, event, helper) {

        // I would love for this to work,
        // but it doesn't work as expected.
        bar(component, event, helper);

        // I've also tried this but get a slightly 
        // different but equally discouraging error.
        this.bar(component, event, helper);
    }
})

Answer 1

try this, it works perfectly

({
    bar : function(component, event, helper) {
        console.log('bar just happened');
    },
    foo : function(component, event, helper) {

        // I would love for this to work,
        // but it doesn't work as expected.
        //bar(component, event, helper);

        // I've also tried this but get a slightly 
        // different but equally discouraging error.
        //this.bar(component, event, helper);

        var a = component.get('c.bar');
        $A.enqueueAction(a);


    }
})

Answer 2

The shortest way of calling a controller function from another controller function you can use:

$A.enqueueAction(component.get('c.controllerMethod'));

When you are calling a helper function from a controller function you can use:

helper.helperMethod(component, event, helper);

When you are calling a helper function from a helper function you can use:

this.helperMethod(component, event, helper);

However, if you are calling a helper function from a helper function, but within a callback method you need to do the following:

// Here we assign the value of this into the self variable
var self = this;

var action = component.get('c.serverSideControllerMethod');

action.setCallback(this, function(response){
    var state = response.getState();

    if(state == 'SUCCESS'){
        // Code here.

        // Here we trigger the helper method with the self variable previously defined
        self.helperMethod(component, event, helper);
        // If we call this.helperMethod(component, event, helper); here it will look at this in the context of the callback function NOT the helper function
    }
})

Answer 3

I find this link:

How to call one controller function from another controller function in Lightning?

From me you can use:

Controller:

foo : function(component, event, helper) {
    helper.bar(component, event, helper);
}

Helper:

bar : function(component, event, helper) {
        console.log('bar just happened');
    }

OR:

I find aura method - documentation https://developer.salesforce.com/docs/atlas.en-us.lightning.meta/lightning/ref_tag_method.htm

this look like that:

In component:

<aura:method name="bar" action="{!c.foo}"
  description="Sample method with parameters">
    <aura:attribute name="parametr" type="String" default="valueOfParam" />
</aura:method>

Controller:

foo : function(component, event, helper) {
    component.bar(parametr);
}

Let me know if this help you.

Answer 4

If I do need to add a method in controller which I can use from multiple places then I add that method in component attribute in doing.

doinit: function doinit(component){
      component.reusableMethod = function(attribute){
           console.log(attribute);
      }
},
action1: function action1(component) {
    component.reusableMethod('action1'); 
},
action2: function action2(component) {
    component.reusableMethod('action2'); 
}

Generally I don't do so. Only Scenario where I do use above method is, if i have to release a patch and we do not have any helper file. We cannot add any helper file in patch release.

Answer 5

As per my knowledge, you can't call other methods of lightning controller from the same lightning controller method. But, you can call other methods of helper from the helper. To call other helper methods, you will have to use this keyword.

Example:

ExampleController.js :

onValueChange : function(component, event, helper){

         helper.callMethodOne(component, event);

}

ExampleHelper.js :

callMethodOne : function(component, event){

         this.callMethodTwo(component, event);

},

callMethodTwo : function(component, event){

         console.log("calling callMethodTwo");

         // Your re-usable code inside the related Component.

}

Note : Whenever you call helper method from controller, the calling method of controller should have below 3 parameters in the exact same order.

1. component. 2. event 3. helper

Answer 6

If you want to call a function from another function you will need to have the two functions defined in your lightning helper rather than the lightning controller.

You can then call

bar : function(component, event, helper) {
    console.log('bar just happened');
},
foo : function(component, event, helper) {
    this.bar(component, event, helper);
}

Answer 7

Lightning has been enhanced with a way to call a controller function after this question was posted in 2017.

You can declare the target controller function using the tag aura:method like below:

<aura:method name="barMethod" action="{!c.bar}" 
             description="bar controller function" />

Then you can reference it on the controller:

({
    bar : function(component, event, helper) {
        // Do something cool
    },
    foo : function(component, event, helper) {
        // This is how you call bar() from here
        component.barMethod();
    }
})

If you need to pass a parameter other than those 3, you'll need to add an aura:attribute tag to the aura:method:

<aura:method name="barMethod" action="{!c.bar}"
      description="bar controller function">
    <aura:attribute name="param1" type="the type" default="default value" />
</aura:method>

And the bar function needs to extract the parameter from the event like below:

var params = event.getParam( 'arguments' );
if( params ) {
   var param1 = params.param1;
   // rest of the code here
}

See more at: Calling Component Methods