CODEWITHSUNDEEP
javascript
Rocky
Rocky

Reputation: 415

How to call parent functions from inner nested function?

I have a simple jQuery ready event that initializes a view by calling the a function in the setupView object.

The question I have is, what is appropriate way to call the function setSomethingImportant from the init function as shown below?

Since the call is made from a different execution context than the init function, this.setSomethingImportant() does not work. However it works if I use setupView.setSomethingImportant(). The problem I have with this is that if the var name (setupView) changes, I will have to change the body of the code as well. 

   (function() {        
        $(document).ready(function() {              
            setupView.init();               
        });     
         var setupView = {          
            currentState : "CT",            
            init : function () {
               $("#externalProtocol").change( function () {
                    console.log("Changed =" + $(this).val());
                    setSomethingImportant(); 
                               // Question ? how to call a method in the setupView object   
                });         
             },         
             setSomethingImportant : function () {
                 this.currentState="TC";    
                 console.log("Something has changed :" + this.currentState );
             }      
         }  
 }(jQuery);

Upvotes: 3

Views: 1926

Answers (3)

dana
dana

Reputation: 18155

Please note that I changed my original solution. I am now passing data to the event handler using even.data.

(function() {        
    $(document).ready(function() {              
        setupView.init();               
    });     
    var setupView = {          
        currentState : "CT",            
        init : function () {
            $("#externalProtocol").change({ _this: this }, function (event) {
                console.log("Changed =" + $(this).val());
                event.data._this.setSomethingImportant(); 
            });         
        },         
        setSomethingImportant : function () {
            this.currentState="TC";    
            console.log("Something has changed :" + this.currentState );
        }      
    }  
 }(jQuery);

Upvotes: 1

Florent
Florent

Reputation: 12420

Store this into a variable:

var setupView = {
    currentState: "CT",
    init: function() {
        // Keep a reference to 'this'
        var self = this;
        $("#externalProtocol").change(function() {
            console.log("Changed =" + $(this).val());

            // Use the old 'this'
            self.setSomethingImportant();
        });
    },
    setSomethingImportant: function() {
        this.currentState = "TC";
        console.log("Something has changed :" + this.currentState);
    }
};

See the Working demo.

Upvotes: 4

xcopy
xcopy

Reputation: 2288

Just declare the function separately and then call like so:

function setSomethingImportant(context) {
    context.currentState="TC";    
    console.log("Something has changed :" + context.currentState );
};

(function() {        
        $(document).ready(function() {              
            setupView.init();               
        });     
         var setupView = {          
            currentState : "CT",            
            init : function () {
               $("#externalProtocol").change( function () {
                    console.log("Changed =" + $(this).val());
                    setSomethingImportant(this); 
                               // Question ? how to call a method in the setupView object   
                });         
             },         
             setSomethingImportant : function () {
                 setSomethingImportant(this);
             }      
         }  
}(jQuery);

Upvotes: 1

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