## wxNotifyEvent

This class is not used by the event handlers by itself, but is a base class for other event classes (such as wxNotebookEvent).

It (or an object of a derived class) is sent when the controls state is being changed and allows the program to Veto() this change if it wants to prevent it from happening.

In some rare cases (so far only dragging the items in the tree control) the event is disabled by default in which case Allow() may be called to allow it.

If both Allow() and Veto() are called, only the last method called counts.

Derived from

wxCommandEvent
wxEvent
wxEvtHandler
wxObject

Include files

<wx/event.h>

Event table macros

None

See also

wxNotebookEvent

Members

wxNotifyEvent::wxNotifyEvent
wxNotifyEvent::Allow
wxNotifyEvent::IsAllowed
wxNotifyEvent::Veto

### wxNotifyEvent::wxNotifyEvent

wxNotifyEvent(wxEventType eventType = wxEVT_NULL, int id = 0)

Constructor (used internally by wxWindows only).

### wxNotifyEvent::Allow

void Allow(bool allow = TRUE)

Allow the action signalled by this event to be carried.

### wxNotifyEvent::IsAllowed

bool IsAllowed() const

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

### wxNotifyEvent::Veto

void Veto()

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.