com.google.gwt.geolocation.client
Class Geolocation

java.lang.Object
  com.google.gwt.geolocation.client.Geolocation

public class Geolocation
extends java.lang.Object

Implements the HTML5 Geolocation interface.

You can obtain a user's position by first calling Geolocation.getIfSupported()

Once you have a Geolocation, you can request the user's current position by calling getCurrentPosition(Callback) or watchPosition(Callback).

The first time an application requests the user's position, the browser will prompt the user for permission. If the user grants permission, the browser will locate the user and report it back to your application. If the user declines permission, the callback's Callback.onFailure(Object) method will be called with a PositionError with its code set to PositionError.PERMISSION_DENIED.

Experimental API: This API is still under development and is subject to change.

This may not be supported on all browsers.

See Also:

W3C Geolocation API, Dive Into HTML5 - Geolocation

Geolocation

protected Geolocation()

Should be instantiated by getIfSupported().

getIfSupported

public static Geolocation getIfSupported()

Returns a Geolocation if the browser supports this feature, and null otherwise.

isSupported

public static boolean isSupported()

Returns true if the browser supports geolocation.

clearWatch

public void clearWatch(int watchId)

Stops watching the user's position.

Parameters:

watchId - the ID of a position watch as returned by a previous call to watchPosition(Callback).

getCurrentPosition

public void getCurrentPosition(Callback<Position,PositionError> callback)

Calls the callback with the user's current position.

getCurrentPosition

public void getCurrentPosition(Callback<Position,PositionError> callback,
                               Geolocation.PositionOptions options)

Calls the callback with the user's current position, with additional options.

watchPosition

public int watchPosition(Callback<Position,PositionError> callback)

Repeatedly calls the given callback with the user's position, as it changes.

The frequency of these updates is entirely up to the browser. There is no guarantee that updates will be received at any set interval, but are instead designed to be sent when the user's position changes. This method should be used instead of polling the user's current position.

Returns:

the ID of this watch, which can be passed to clearWatch(int) to stop watching the user's position.

watchPosition

public int watchPosition(Callback<Position,PositionError> callback,
                         Geolocation.PositionOptions options)

Repeatedly calls the given callback with the user's position, as it changes, with additional options.

The frequency of these updates is entirely up to the browser. There is no guarantee that updates will be received at any set interval, but are instead designed to be sent when the user's position changes. This method should be used instead of polling the user's current position.

If the browser does not support geolocation, this method will do nothing, and will return -1.

Returns:

the ID of this watch, which can be passed to clearWatch(int) to stop watching the user's position.