Script does not allow geolocation.getCurrentPosition to complete its callback function

Question

I need to pack the user's current location into an object and send it to a PHP script. So, I currently have the following.

position object

function position(lat, lon) {
    this.latitude = lat;
    this.longitude = lon;

    this.setlat = function(lat) {
        this.latitude = lat;
    };

    this.setlon = function(lon) {
        this.longitude = lon;
    };

    this.print = function() {
        alert(this.longitude + ", " + this.latitude);
    };
}

control flow

var origin = new position(0, 0);

$(document).ready(function() {

    getLocation();
    origin.print();


});

Functions

function getLocation() {

    if (navigator.geolocation) {
        navigator.geolocation.getCurrentPosition(setLocation, showError, {timeout:60000});
    } else {
        alert("GeoLocation is not supported on this browser or device.");
        return null;
    }

}

function setLocation(position) {
    alert('callback success!');
    origin.setlat(position.coords.latitude);
    origin.setlon(position.coords.longitude);
}

function showError(error) {
    switch(error.code) {
        case error.PERMISSION_DENIED:
            console.log("User denied the request for Geolocation.");
            break;
        case error.POSITION_UNAVAILABLE:
             console.log("Location information is unavailable.");
            break;
        case error.TIMEOUT:
             console.log("The request to get user location timed out.");
            break;
        case error.UNKNOWN_ERROR:
             console.log("An unknown error occurred.");
            break;
    }
}

The problem is that before the callback is called, the setLocationmain control flow continues and ignores the fact that I asked him to get something for me. I call getLocation and I get the warning "0, 0", since it was initially set. Therefore, for some reason, my callback is setLocationsimply not called until everything else in the program is completed.

I looked through the documentation, but it is quite simple, and not so much happens, so it is difficult to determine why this is happening.

, , , , - " ", , , , -.

, , , .

navigator.geolocation.getCurrentPosition() while, , .

- maximumAge timeout PositionOptions, , setLocation .

- $(document).ready(function(){});, getLocation() origin.print().

- watchPosition getCurrentPosition.

, getCurrentPosition , .

Answer 1

, getCurrentPostion, Javascript , . jQuery $.Deferred object, , .

function getLocation() {

    var deferred = $.Deferred();

    setTimeout(function() {
        navigator.geolocation.getCurrentPosition(function(pos) {

            origin = new position(pos.coords.latitude, pos.coords.longitude);
            deferred.resolve();

        });

    }, 2000);
    // 2.00 seconds
    return deferred.promise();
}

, origin deferred.resolve() .

getLocation(), , , , , getLocation(), , .

getLocation().done( function() {
    origin.print();
    //do other stuff with origin
});

, - , getCurrentPosition, , Google Maps.

Answer 2

:

var origin = new position(0, 0);

$(document).ready(function() {

    getLocation();
    origin.print();


});

var origin = new position(0, 0);

$(document).ready(function() {

    getLocation();

});

function getLocation() {

    if (navigator.geolocation) {
        navigator.geolocation.getCurrentPosition(setLocation, showError, {timeout:60000});
    } else {
        alert("GeoLocation is not supported on this browser or device.");
        return null;
    }
}

// this is the callback
function setLocation(position) {
    alert('callback success!');
    origin.setlat(position.coords.latitude);
    origin.setlon(position.coords.longitude);
    // this is a new function that makes stuff
    processLocation();
}

// do your stuff here
function processLocation(){
    origin.print();
    // do your stuff here like comparing to other locations or sending data
    if (origin.latitude == something) blah...
}

setLocation