Notes by Collin

Current Location with Javascript

July 1st, 2012 • 2 notes

Both Breeze, and another little mobile app I’m working on utilize javascript’s geolocation API. It’s actually very easy to obtain a users longitude and latitude with this API, using the following snippet:

if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(function (position) {
        var lat = (position.coords.latitude);
        var lon = (position.coords.longitude);
    }, // next function is the error callback 
    function (error) {
        switch (error.code) {
        case error.TIMEOUT:
            alert('A timeout has occured, and your location was unable to be determined.');
            break;
        case error.POSITION_UNAVAILABLE:
            alert('Your current position was not able to be retrieved. This is most likely due to a lack of network connectivity.');
            break;
        case error.PERMISSION_DENIED:
            alert('Unable to retrieve your location because permission was denied. Please ensure location services are turned on for Safari.');
            break;
        case error.UNKNOWN_ERROR:
            alert('An unknown error occured. :(');
            break;
        }
    });
}

Easy right? Once you have a user’s coordinates, you can use all kinds of location based API’s to write to neat apps and features.