You can attach StateChange event like below
Xrm.Page.data.process.addOnStageChange(functionname)
You can attach StateSelected event like below
Xrm.Page.data.process.addOnStageSelected(functionname)
You can attach StateChange event like below
Xrm.Page.data.process.addOnStageChange(functionname)
You can attach StateSelected event like below
Xrm.Page.data.process.addOnStageSelected(functionname)