private void OnObjectDestroyed(ALayer arg1, AObject arg2)
{
if (this.mappingObjectToObject2D.ContainsKey(arg2))
{
LayerObject2D layer = this.mappingLayerToLayerObject2D[arg1];
AObject2D object2D = this.mappingObjectToObject2D[arg2];
layer.RemoveObject2D(object2D);
this.mappingObjectToObject2D.Remove(arg2);
}
}