A callback is a class method called by a control on sudden events, such as when the user clicks the control, the control resizes or changes.

All callback methods has a standard signature :

  methodname(self,sender,args)

where self is the class instance, sender is the actual control calling the event and args is variable due to context/event

  class InspectionCounterPlugin(object):
    
    def __init__(self,cntr,name):
      self.name=name

      self.panel=cntr.addControl('Panel',0,0)
      self.panel.align=5  #client
      self.panel.caption='Inspections=%d' % self.count
      
      self.panel.onResize  = self.panelResize
      self.panel.onClick = self.panelClick
      

    def panelResize(self,sender,args):
      print 'panelResize',self,sender,args

    def panelClick(self,sender,args):
      print 'panelClick',self,sender,args