/// <inheritdoc/>
public Task <bool> StopListeningAsync()
{
if (listener == null)
{
return(Task.FromResult(true));
}
if (listeningProviders == null)
{
return(Task.FromResult(true));
}
var providers = listeningProviders;
listener.PositionChanged -= OnListenerPositionChanged;
listener.PositionError -= OnListenerPositionError;
for (var i = 0; i < providers.Count; i++)
{
try
{
Manager.RemoveUpdates(listener);
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("Unable to remove updates: " + ex);
}
}
listener = null;
return(Task.FromResult(true));
}
/// <summary>
/// Start listening for changes
/// </summary>
/// <param name="minimumTime">Time</param>
/// <param name="minimumDistance">Distance</param>
/// <param name="includeHeading">Include heading or not</param>
/// <param name="listenerSettings">Optional settings (iOS only)</param>
public async Task <bool> StartListeningAsync(TimeSpan minimumTime, double minimumDistance, bool includeHeading = false, ListenerSettings listenerSettings = null)
{
var hasPermission = await CheckPermissions();
if (!hasPermission)
{
throw new GeolocationException(GeolocationError.Unauthorized);
}
var minTimeMilliseconds = minimumTime.TotalMilliseconds;
if (minTimeMilliseconds < 0)
{
throw new ArgumentOutOfRangeException(nameof(minimumTime));
}
if (minimumDistance < 0)
{
throw new ArgumentOutOfRangeException(nameof(minimumDistance));
}
if (IsListening)
{
throw new InvalidOperationException("This Geolocator is already listening");
}
var providers = Providers;
listener = new GeolocationContinuousListener(Manager, minimumTime, providers);
listener.PositionChanged += OnListenerPositionChanged;
listener.PositionError += OnListenerPositionError;
var looper = Looper.MyLooper() ?? Looper.MainLooper;
listeningProviders.Clear();
for (var i = 0; i < providers.Length; ++i)
{
var provider = providers[i];
//we have limited set of providers
if (ProvidersToUseWhileListening != null &&
ProvidersToUseWhileListening.Length > 0)
{
//the provider is not in the list, so don't use it.
if (!ProvidersToUseWhileListening.Contains(provider))
{
continue;
}
}
listeningProviders.Add(provider);
Manager.RequestLocationUpdates(provider, (long)minTimeMilliseconds, (float)minimumDistance, listener, looper);
}
return(true);
}
