Trigger function when Picker changes

Hi,

I have a picker of style SegmentedPickerStyle and based on the selection (Inbound, Outbound) a chart below displays different data. How can I send an event to my chart model to reload the data based on the picker selection? I know how to send the picker value to the model but how do I trigger it every time when the picker changes?

I have tried something like

SunburstView(configuration: self.sunburstController.configuration).onAppear{
  self.sunburstController.loadNodes(countMode: self.selectedCountMode, direction: self.selectedDirection)
  }

but that obviously only works first time the view is loading and not after every picker change.

Thanks for any hints!

Max