Geolocation

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AppStudio programs can use the capabilities of the web browser. As a result, they can inherit a lot of the properties of the environment they run in. You can access these properties from within your app.

It is not a complete list: there are additional items in the full HTML documentation. In addition, some browsers may have additional properties not shown here.

On iOS, In Settings...Privacy...Location Sevices, make sure that Safari is set to "While using the App". It will then request permission when geolocation is used. The app needs to be loaded to your device using https: if you load using http, the OS will not allow you to use geolocation.

navigator.geolocation.getCurrentPosition(successFunction[, errorFunction[, parameters]])

successFunction(required) is the name of a function in your program, which will be called by the above statement. It is passed a single parameter: an object with the Geolocation Object Members:

errorFunction (optional) is the name of the function to call if the operation fails. It returns (code, message).

parameters (optional) is a PositionOptions object (see below) with information how the call should work.

Geolocation Object Members

location.coords.longitude The current longitude of the device. GPS required.
location.coords.latitude The current latitude of the device. GPS required.
location.coords.altitude The height of the location. GPS required.
location.coords.accuracy The accuracy of the location. GPS required.
location.coords.altitudeAccuracy The accuracy of the altitude. GPS required.
location.coords.heading Degrees clockwise from North. GPS required.
location.coords.speed Speed, meters per second. GPS required.
location.coords.timestamp time and date of the observation. GPS required.

PositionOptions Object Members

enableHighAccuracy True/False. May take a bit longer.
timeout Milliseconds to wait for the result.
maximumAge Use a cached result if within the specified number of milliseconds.

For more information on Google Maps, read http://code.google.com/apis/maps/documentation/staticmaps/.

Example

REM Geolocation
Function handler(location)
  Dim s
  Print "Longitude: " + location.coords.longitude 
  Print "Latitude: " + location.coords.latitude 
  Print "Accuracy: " + location.coords.accuracy
  s = "<img src='http://maps.google.com/maps/api/staticmap?center=" & _
  location.coords.latitude & "," & location.coords.longitude & _
  "&zoom=14&size=300x200&maptype=roadmap'>"
  print s
End Function

navigator.geolocation.getCurrentPosition(handler);

Example (JavaScript)

// Geolocation

function handler(location) {
  var s;
  NSB.Print("Longitude: " + location.coords.longitude);
  NSB.Print("Latitude: " + location.coords.latitude);
  NSB.Print("Accuracy: " + location.coords.accuracy);
  s = "<img src='http://maps.google.com/maps/api/staticmap?center=";
  s += location.coords.latitude + "," + location.coords.longitude;
  s += "&zoom=14&size=300x200&maptype=roadmap'>";
  NSB.Print(s);
}

navigator.geolocation.getCurrentPosition(handler);

Output

Longitude: -79.2098782
Latitude: 43.73776441
Accuracy: 100
(map of current location)