Call event on PropertyChanged

Hi mates,

I am trying to call a method from the API when a node is set as input as the following;

private void CurrentWorkspaceModel_PropertyChanged(NodeModel obj)
    {
        RaisePropertyChanged("ActiveNodeTypes");
    }

I got it working when a node is added and removed as explained in https://github.com/DynamoDS/DynamoSamples/tree/master/src/SampleViewExtension but I cannot find the way on property change?

Any help would be much appreciated.
Thanks