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JavaScript

Posted by evanritscher
evanritscher
10,209 Points

Cannot understand async javascript

I am trying to record a browser's longitude and latitude with a lot of frustration.

I know that it is an asynchronous process but cannot seem to figure out how to handle that.

I can't see what I need to do to create the function that goes out and looks for the coordinates and then fills the global variables once it's received them.

if someone could walk me through this, I'd be eternally grateful.

Here is what I have so far and I am stuck: 

var userLong;
var userLat;  
$(document).ready(function(){


function currentLocal(coordinates){

    if(navigator.geoLocation){
        navigator.geolocation.getCurrentPosition(function(position){
        userLat = position.coords.latitude;
        userLong = position.coords.longitude;

    });
}}

1 Answer

evanritscher
evanritscher
10,209 Points
evanritscher
evanritscher
10,209 Points

So I've somehow seemed to get something that works but I don't understand why, how or what it does. Could someone please walk me through what's going here: 

var userLong;
var userLat;  
$(document).ready(function(){


    function currentLocal(callback){

            navigator.geolocation.getCurrentPosition(
            function(position){
            userLat = position.coords.latitude;
            userLong = position.coords.longitude;
            callback();

        })
    }

function findLong(){
    (userLong)

}

    currentLocal(findLong)
})