/// <summary>
/// Validate whether the new (temp) geometry can be saved - is it valid?
/// </summary>
/// <returns>valid/not valid</returns>
private bool CanSaveNewGeom()
{
if (GeometryType == "Punkt")
{
return(TempCoordinates.Count > 0);
}
else if (GeometryType == "Linie")
{
return(TempCoordinates.Count > 1);
}
else
{
var isValid = MapModel.CheckValidityOfPolygon(TempCoordinates);
if (TempCoordinates.Count <= 3)
{
CurrentPolygonSelfIntersecting = false;
}
if (TempCoordinates.Count > 3 && isValid)
{
CurrentPolygonSelfIntersecting = false;
return(true);
}
else
{
if (TempCoordinates.Count > 3)
{
if (!CurrentPolygonSelfIntersecting) //Polyon was not previously self-intersecting
{
CurrentPolygonSelfIntersecting = true;
Device.BeginInvokeOnMainThread(async() =>
{
bool ok = await App.Current.MainPage.DisplayAlert("Das aktuelle Polygon schneidet sich selbst", "Solange es eine ungültige Geometrie hat kann es nicht gespeichert werden", "Weiter zeichnen", "Rückgängig machen");
if (!ok)
{
try
{
TempCoordinates.RemoveAt(TempCoordinates.Count - 2);
CurrentPolygonSelfIntersecting = false;
MessagingCenter.Send <MapPageVM>(this, "ShapeDrawingUndone");
SaveGeomCommand.ChangeCanExecute();
}
catch (Exception e)
{
Console.WriteLine("Had a problem undoing the shape: " + e.Message);
}
}
});
}
}
return(false);
}
}
}
