__init__(self, commandType=wxEVT_NULL, winid=0)
(Constructor)

An instance of this class (or one of its derived classes) is sent from a control when the control's state is being changed and the control allows that change to be prevented from happening. The event handler can call Veto or Allow to tell the control what to do.

Parameters:

commandType
           (type=wxEventType)

winid
           (type=int)

Returns:

NotifyEvent

Overrides:

wx.CommandEvent.__init__

Allow(self)

This is the opposite of Veto: it explicitly allows the event to be processed. For most events it is not necessary to call this method as the events are allowed anyhow but some are forbidden by default (this will be mentioned in the corresponding event description).

IsAllowed(self)

Returns true if the change is allowed (Veto hasn't been called) or false otherwise (if it was).

Returns:

bool

Veto(self)

Prevents the change announced by this event from happening.

It is in general a good idea to notify the user about the reasons for vetoing the change because otherwise the applications behaviour (which just refuses to do what the user wants) might be quite surprising.