private async Task OnAppearing()
{
if (IsBusy)
{
return;
}
IsBusy = true;
SettingsModel settings = GetSettings();
GeoCacheModel lastGeoCache = settings.GeoCache;
if (!IsLastGeoCacheValid(lastGeoCache))
{
lastGeoCache = await UpdateLastGeoCache(lastGeoCache, settings);
}
if (lastGeoCache == null)
{
lastGeoCache = new GeoCacheModel();
}
Device.BeginInvokeOnMainThread(() =>
{
GeoCachePosition = new Position(lastGeoCache.GeoCacheLatitude, lastGeoCache.GeoCacheLongitude);
});
await StartListeningGps();
StartListeningCompass();
//SleepMode.ActivateAutoSleepMode(false);
IsBusy = false;
}
private bool IsLastGeoCacheValid(GeoCacheModel lastGeoCache)
{
if (lastGeoCache == null || lastGeoCache.GeoCacheLatitude == 0 || lastGeoCache.GeoCacheLongitude == 0)
{
return(false);
}
DateTimeOffset geoCacheHiddenTimestamp =
DateTimeOffset.FromUnixTimeSeconds(lastGeoCache.GeoCacheHiddenTimestamp);
return(DateTimeOffset.Now - geoCacheHiddenTimestamp < TimeSpan.FromDays(6));
}
private async Task UpdateGeoCache()
{
var lastGeoCache = await UpdateLastGeoCache(null, GetSettings());
if (lastGeoCache == null)
{
lastGeoCache = new GeoCacheModel();
}
Device.BeginInvokeOnMainThread(() =>
{
GeoCachePosition = new Position(lastGeoCache.GeoCacheLatitude, lastGeoCache.GeoCacheLongitude);
});
}
private async Task <GeoCacheModel> UpdateLastGeoCache(GeoCacheModel lastGeoCache, SettingsModel settings)
{
try
{
lastGeoCache = await(new DocumentService()).GetDocument();
lastGeoCache.GeoCacheHiddenTimestamp = DateTimeOffset.Now.ToUnixTimeSeconds();
settings.GeoCache = lastGeoCache;
Settings.GeneralSettings = JsonConvert.SerializeObject(settings);
}
catch (Exception ex)
{
Debug.WriteLine(ex);
lastGeoCache = new GeoCacheModel();
}
return(lastGeoCache);
}
public async Task <GeoCacheModel> GetDocument()
{
GeoCacheModel geoCacheInfos = null;
using (HttpClient client = GetHttpClient())
{
var url = _baseCloudantUrl + _documentName;
var response = await client.GetAsync(url);
if (response?.StatusCode == HttpStatusCode.OK)
{
var responseAsString = await response.Content.ReadAsStringAsync();
geoCacheInfos = JsonConvert.DeserializeObject <GeoCacheModel>(responseAsString);
}
}
return(geoCacheInfos);
}
