private void OnAreaChanged(LatLonRect oldArea, LatLonRect newArea)
{
if ((ZoomLevel < SmallThreshold && lastZoomLevel != -1) || (newArea.Span.Latitude > MAX_LAT_RANGE * 8 || newArea.Span.Longitude > MAX_LON_RANGE * 8))
{
ShownStops.Clear();
PendingRegions.Clear();
}
else
{
IEnumerable <LatLonRect> newRegion;
if (lastZoomLevel < SmallThreshold)
{
newRegion = new LatLonRect[] { newArea }
}
;
else
{
newRegion = oldArea.GetNewRegion(newArea);
}
AppendRegions(newRegion);
if (!IsBusy)
{
RefreshShownStops(TokenSource.Token, !ManuallyDownloadStops);
}
}
lastZoomLevel = ZoomLevel;
}
protected async void RefreshShownStops(CancellationToken token, bool download = false)
{
IsBusy = true;
try
{
if (ZoomLevel < SmallThreshold)
{
ShownStops.Clear();
}
else
{
//var toRemove = ShownStops.Where(stop => !Area.ContainsLatLon(stop.Position)).ToArray();
//ShownStops.RemoveRange(toRemove);
var area = Area;
for (int i = 0; i < ShownStops.Count; i++)
{
if (!area.ApplySubset(OuterStopCacheMargin).ContainsLatLon(ShownStops[i].Position))
{
ShownStops.RemoveAt(i);
i--;
}
}
var fwtc = MemoryCache.GetStop("FWTC");
if (fwtc.HasValue && area.ContainsLatLon(fwtc.Value.Position))
{
ShownStops.Add(fwtc.Value);
}
while (PendingRegions.Count > 0)
{
var region = PendingRegions.Dequeue();
//var fwtc = new string[] { "1_80439", "1_80431", "1_80438", "1_80432", "1_80437", "1_80433", "3_27814", "3_29410" };
if (region.Intersects(area))
{
var sResult = await DataSource.GetTransitStopsForAreaAsync(region, download?DataSourcePreference.All : DataSourcePreference.OfflineSources, token);
var stops = sResult.Data.Where(stop => !ShownStops.Contains(stop));
//var fwtcStop = new TransitStop() { ID = "FWTC", Position = new LatLon(47.31753, -122.30486), Path = "_vx_HlnniVF??LJ??MF??nIG??MK??LG?", Name = "Federal Way Transit Center" };
//TransitStop.SqlProvider.Insert(fwtcStop, DatabaseManager.MemoryDatabase);
if (stops == null)
{
return;
}
Cache.Add(stops.ToArray());
ShownStops.AddRange(stops);
}
//foreach (var stop in stops)
//{
// if (!ShownStops.Any(stp => stp.ID == stop.ID))
// ShownStops.Add(stop);
//}
}
}
}
catch (HttpRequestException)
{
PendingRegions.Clear();
}
catch (OperationCanceledException)
{
}
finally
{
IsBusy = false;
}
}