public VectorTileLayer(string layername, SymbolProvider symbolProvider) : base(layername)
 {
     SymbolProvider = symbolProvider ?? throw new ArgumentException("SymbolProvider must not be null");
 }
 public VectorTileLayer(SymbolProvider symbolProvider) : base()
 {
     SymbolProvider = symbolProvider ?? throw new ArgumentException("SymbolProvider must not be null");
 }