Array.length reading 0 after pushing objects on array

Question

I'm trying to push objects on to array and process the array as a queue. Nothing is currently removing anything from the array, and each time the acme.addToValidateQueue function is called ( several times in succession ) it always shows 1 as the array length. What am I doing wrong?

var acme = {};
acme.validateQueue = [];
acme.validateQueueLastIndex = 0;

acme.addToValidateQueue = function(fieldData,fieldName){
    var queueItem = {
        index : acme.validateQueueLastIndex,
        fieldData : fieldData,
        fieldName : fieldName
    };
    acme.validateQueue.push(queueItem);
    acme.validateQueueLastIndex++;
    console.log(acme.validateQueue.length); // shows 1 everytime the queue is called.
    if(acme.validateQueue.length === 1){
        acme.processValidateQueue();
    };
}

acme.processValidateQueue = function(){
    if(acme.validateQueue.length){
        acme.validate_field(acme.validateQueue.shift());
    }
}

Are you sure you're not doing this with a new `acme` and `acme.validateQueue` every time? — user2357112, Aug 29 '14 at 22:19
And shouldn't you be using `this` in the method instead of `acme`, so the method uses the instance it's being called on instead of the `acme` variable? — user2357112, Aug 29 '14 at 22:20
@PabloMatíasGomez acme.validate_field(acme.validateQueue.shift()); — cactusphone, Aug 29 '14 at 22:26
Then it seems your question might be a duplicate of http://stackoverflow.com/questions/14220321/how-to-return-the-response-from-an-ajax-call — elclanrs, Aug 29 '14 at 22:30
As pointed out, you ARE removing items from the queue. shift() removes the first item from the array and returns it. So if you push an item into the array, and then promptly call something that performs a shift, then you are, as the answer below states, immediately removing the item you just pushed. — Thomas W Tupper, Aug 29 '14 at 22:59

score 2 · Answer 1 · answered Aug 29 '14 at 22:38

Every time you call addToValidateQueue, that calls processValidateQueue, which promptly removes the item you just added:

acme.validate_field(acme.validateQueue.shift());
//                            Right here ^

That means that on the next call, you only see the item you're adding on that call. The old item is gone.

Array.length reading 0 after pushing objects on array

1 Answers1