So a little background for my question; I am writing a simple driving instructions web application using Google Maps directions API which provides me with a LatLng path along with text instructions.
In order to test this application (without driving around in a car) I need to simulate a geolocation-path. Google Chrome supports overriding geolocation data via the sensors developer settings, which works fine with one coordinate at the time.
So my question is - is it possible to set the browsers navigator.geolocation data via the console (i.e. javascript api) instead manually updating the value in the sensors settings menu?
I know that in this case I could just use another input source than the browser geolocation data and use a static array of LatLng's, or override the browsers navigator.geolocation.getCurrentPosition, but I figured that it would be more sophisticated to override the sensors instead.
Thanks in advance.
One way is to override the function navigator.geolocation.getCurrentPosition with your own custom function. Inside the custom function you can customize the value of latitude & longitude.
var customPosition = {};
customPosition.coords = {};
customPosition.coords.latitude = 41.89;
customPosition.coords.longitude = 2.89;
navigator.geolocation.getCurrentPosition = function(success, error){
success(customPosition);
};
function success(position) {
var latitude = position.coords.latitude;
var longitude = position.coords.longitude;
console.log("latitude: " + latitude);
console.log("longitude: " + longitude);
}
Related
I have script for geolocalization. It's working only when user is on website. When browser is miminalized or tab is inactive, script is not working. How can I fix it?
var int=self.setInterval(function(){getLocation()},2000);
function getLocation()
{
navigator.geolocation.getCurrentPosition(showPosition);
}
function showPosition(position)
{
var latitude = position.coords.latitude;
var longitude = position.coords.longitude;
console.log('Position: '+latitude+' '+longitude);
$.ajax({
type : "POST",
data : { latitude : latitude, longitude : longitude },
url : "mylinktosaveposition",
success : function(data){}
});
}
This is a security feature built into browsers, there is no way to get around this! Browsers simply freeze or shut down scripts when they go inactive to increase performance on active tabs and reduce power usage on battery powered devices. I would recommend creating an app if you are looking into geotracing people for whatever reason. Take a look at ionic which is a framework on cordova which uses angular to built apps for ios and android in javascript/html like language.
I have been working on an app that uses the getCurrentPosition(), but that doesn't work anymore in the latest version of Chrome, see:
Deprecating Powerful Features on Insecure Origins
So my code here doesn't work in latest stable version of Chrome:
var latitude = 0;
var longitude = 0;
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(function(position){
latitude = position.coords.latitude;
longitude = position.coords.longitude;
$("#data").html("latitude: " + latitude + "<br>longitude: " + longitude);
});
}
What are alternatives to getting the user's position with HTML Geolocation API? Any thoughts?
I'm grappling with this myself. If HTTPS is not an option for you, then maybe add a fallback for Chrome where you prompt the user to submit their address. Then have your app geocode it.
I'm currently working on a mobile application with Intel XDK (In background it's Cordova finally, that's why I put Cordova in title.)
With an Ajax request, I get some adresses and with these adresses I want to calculate the distance between them and the current position of user.
So, I get adresses, I convert them and I make the difference.
But actually, nothing is working !
function codeAddress(id, addresse) {
geocoder.geocode( { 'address': addresse}, function(results, status) {
if (status == google.maps.GeocoderStatus.OVER_QUERY_LIMIT) {
setTimeout(function(){}, 100);
}
console.log(id);
console.log(addresse);
//document.addEventListener("intel.xdk.device.ready",function(){
if (navigator.geolocation)
{
if (status == google.maps.GeocoderStatus.OK)
{
navigator.geolocation.getCurrentPosition(function(position) {
addressEvent = results[0].geometry.location;
var pos = {
lat: position.coords.latitude,
lng: position.coords.longitude
};
var position = new google.maps.LatLng(pos.lat, pos.lng)
var resultat = google.maps.geometry.spherical.computeDistanceBetween(addressEvent, position);
console.log(resultat);
console.log(addressEvent);
console.log(pos);
console.log(position);
var convert = Math.floor(resultat);
var finalConvert = convert + " m";
var distance = document.createElement('span');
distance.innerHTML = finalConvert;
distance.className = "geo";
document.getElementsByClassName('meta-info-geo')[id].appendChild(distance);
}, function() {
handleLocationError(true, infoWindow);
});
}
}
//},false);
});
}
In the console.log(id), console.log(addresse), I HAVE results !
Actually i'm getting 4 IDs and 4 adresses.
I checked on all the topics I could find on StackOverFlow, and I had normally to add the line in // with the addEventListener but it changes nothing.
Is there someone who knows how to change that ?
ps : Of course, cordova geoloc is in the build and permissions are granted !
EDIT : I'm targeting Android 4.0 min and iOS 5.1.1. I'm using SDK.
EDIT 2 :
Geolocation frequently does not work the way people expect it to work, for a variety of reasons that have been expressed here and here.
You can experiment with geo by using the "Hello, Cordova" sample app that is in the XDK and also available on GitHub. Try using it on a variety of devices to see how things work. Push the "fine" button to initiate a single geo call for a "fine" location and push the "coarse" button to initiate a single geo call for a "coarse" location. Push the "watch" button to initiate a request for a series of geo data points (set to coarse or fine by pushing one of the single buttons first).
The behavior you get in the Emulate tab will be dramatically different than what you get on a real device. The type of device (Android, iOS, etc.) and the version of that device will influence your results; the manufacturer of the device and your location (inside or outside) will influence your results. Do not assume that making a call to the geo APIs will always give you immediate and reliable data, geolocation hardware does not work that way... In fact, you cannot assume that you can even get a valid result! See the two links I pointed to earlier in the post for some reasons why.
I am building a hybrid mobile application using Intel's App Framework for user interface and Cordova to access the native device functionalities.
As a part of the development, I need to get the user's location(City and Country) and show it in a text box.
By using the code below, I am able to get the Latitude and Longitude and show it in two different text boxes(with ID latitude and longitude respectively). How can I translate the latitude and longitude to City and Country.
function Geolocation() {
var onSuccess = function(position) {
document.getElementById('latitude').value = position.coords.latitude;
document.getElementById('longitude').value = position.coords.longitude;
};
var onFail = function() {
navigator.notification.alert('Cannot get the location');
};
navigator.geolocation.getCurrentPosition(onSuccess, onFail, {maximumAge:0, timeout:5000, enableHighAccuracy: true});
}
Note - I don't use any other plugin other than Cordova's Geolocation to handle location services in my app. This is a hybrid app but currently I am working on the Android version of the app.
This is called reverse geocoding are there are many services out there to do that - eg. Google Maps, OpenStreetMaps and many more.
I love OpenStreetMaps because it's very easy to do. Just a JSONP callback:
http://nominatim.openstreetmap.org/reverse?lat=-23.5880894&lon=-46.6321951&format=json&json_callback=my_callback
So you can just make an Ajax request to this URL and get the desired values. For example:
function showCountry(lat, lon) {
$.getJSON('//nominatim.openstreetmap.org/reverse?json_callback=?&format=json', {lat: lat, lon: lon}, function(data) {
alert(data.address.country);
});
}
I know there are at least a couple of questions like this
detecting "we have no imagery" of google maps street view static images
How can I tell if Google's Streetview Image API Returns "Sorry, we have no imagery here" (ie. NULL) Result?
These articles offer a couple of solutions. The two most popular I've seen here and via Google searaches are:
Detecting the size of the image to determine if you got a "good" image or not from the google static image API
Call the getPanoramaByLocation service to determine if streetview is available for a location
Unfortunately, I don't want to use the first solution because it feels like the hack, and the second solution does not always seem to work.
var center = new google.maps.LatLng(latitude, longitude);
var streetViewService = new google.maps.StreetViewService();
var maxDistanceFromCenter = 75; //meters
streetViewService.getPanoramaByLocation(center, maxDistanceFromCenter, function (streetViewPanoramaData, status) {
if (status === google.maps.StreetViewStatus.OK) {
var key = /**smarty** #mapKey# **smarty**/;
var url = 'http://maps.googleapis.com/maps/api/streetview?size=320x320&location=' + latitude + ',%20' + longitude + '&sensor=false&key=' + key;
jQuery('.ui-page-active .streetView').attr('src', url);
} else {
console.log('error calling street view');
}
});
};
This code will correctly determine if panoramic imagery is available for a location, BUT sometimes static imagery is not available for that exact same location.
I started at 100 for my getPanoramaByLocation radius and that seemed like a safe number, but then I found a case where I was getting the "Sorry, we have no imagery here" error. So I went to 75, now I have to go to 50.
It seems like getPanoramaByLocation is not a safe indicator of static streetview imagery being available, or maybe it is but there's a particular value for the radius that should be used. I can't find it in the docs though. So my question: what's the safest radius to use for my maxDistanceFromCenter?