END_EVENT_TABLE()
\end{verbatim}
-The first two entries map menu commands to two different member functions. The EVT\_SIZE macro
-doesn't need a window identifier, since normally you are only interested in the
-current window's size events. (In fact you could intercept a particular window's size event
-by using EVT\_CUSTOM(wxEVT\_SIZE, id, func).)
-
-The EVT\_BUTTON macro demonstrates that the originating event does not have to come from
-the window class implementing the event table - if the event source is a button within a panel within a frame, this will still
-work, because event tables are searched up through the hierarchy of windows. In this
-case, the button's event table will be searched, then the parent panel's, then the frame's.
-
-As mentioned before, the member functions that handle events do not have to be virtual.
-Indeed, the member functions should not be virtual as the event handler ignores that
-the functions are virtual, i.e. overriding a virtual member function in a derived class
-will not have any effect.
-These member functions take an event argument, and the class of event differs according
-to the type of event and the class of the originating window. For size
-events, \helpref{wxSizeEvent}{wxsizeevent} is used. For menu commands and most control
-commands (such as button presses), \helpref{wxCommandEvent}{wxcommandevent} is used.
-When controls get more complicated, then specific event classes are used, such
-as \helpref{wxTreeEvent}{wxtreeevent} for events from \helpref{wxTreeCtrl}{wxtreectrl} windows.
-
-As well as the event table in the implementation file, there must be a DECLARE\_EVENT\_TABLE
-macro in the class definition. For example:
+The first two entries map menu commands to two different member functions. The
+EVT\_SIZE macro doesn't need a window identifier, since normally you are only
+interested in the current window's size events.
+
+The EVT\_BUTTON macro demonstrates that the originating event does not have to
+come from the window class implementing the event table -- if the event source
+is a button within a panel within a frame, this will still work, because event
+tables are searched up through the hierarchy of windows for the command events.
+In this case, the button's event table will be searched, then the parent
+panel's, then the frame's.
+
+As mentioned before, the member functions that handle events do not have to be
+virtual. Indeed, the member functions should not be virtual as the event
+handler ignores that the functions are virtual, i.e. overriding a virtual
+member function in a derived class will not have any effect. These member
+functions take an event argument, and the class of event differs according to
+the type of event and the class of the originating window. For size events,
+\helpref{wxSizeEvent}{wxsizeevent} is used. For menu commands and most
+control commands (such as button presses),
+\helpref{wxCommandEvent}{wxcommandevent} is used. When controls get more
+complicated, then specific event classes are used, such as
+\helpref{wxTreeEvent}{wxtreeevent} for events from
+\helpref{wxTreeCtrl}{wxtreectrl} windows.
+
+As well as the event table in the implementation file, there must also be a
+DECLARE\_EVENT\_TABLE macro somewhere in the class declaration. For example:
{\small%
\begin{verbatim}
-class MyFrame: public wxFrame {
-
- DECLARE_DYNAMIC_CLASS(MyFrame)
-
+class MyFrame : public wxFrame
+{
public:
...
void OnExit(wxCommandEvent& event);
void OnSize(wxSizeEvent& event);
+
protected:
int m_count;
...
+
DECLARE_EVENT_TABLE()
};
\end{verbatim}
}%
+Note that this macro may occur in any section of the class (public, protected
+or private) but that it is probably better to insert it at the end, as shown,
+because this macro implicitly changes the access to protected which may be
+quite unexpected if there is anything following it.
+
+Finally, if you don't like using macros for static initialization of the event
+tables you may also use \helpref{wxEvtHandler::Connect}{wxevthandlerconnect} to
+connect the events to the handlers dynamically, during run-time. See the
+\helpref{event sample}{sampleevent} for an example of doing it.
+
+
\subsection{How events are processed}\label{eventprocessing}
When an event is received from the windowing system, wxWindows calls
\item If the object is disabled (via a call to \helpref{wxEvtHandler::SetEvtHandlerEnabled}{wxevthandlersetevthandlerenabled})
the function skips to step (6).
\item If the object is a wxWindow, {\bf ProcessEvent} is recursively called on the window's\rtfsp
-\helpref{wxValidator}{wxvalidator}. If this returns TRUE, the function exits.
+\helpref{wxValidator}{wxvalidator}. If this returns true, the function exits.
\item {\bf SearchEventTable} is called for this event handler. If this fails, the base
class table is tried, and so on until no more tables exist or an appropriate function was found,
in which case the function exits.
\item The search is applied down the entire chain of event handlers (usually the chain has a length
of one). If this succeeds, the function exits.
\item If the object is a wxWindow and the event is a wxCommandEvent, {\bf ProcessEvent} is
-recursively applied to the parent window's event handler. If this returns TRUE, the function exits.
+recursively applied to the parent window's event handler. If this returns true, the function exits.
\item Finally, {\bf ProcessEvent} is called on the wxApp object.
\end{enumerate}
\subsection{Window identifiers}\label{windowids}
-\index{identifiers}\index{wxID}Window identifiers are integers, and are used to uniquely determine window identity in the
-event system (though you can use it for other purposes). In fact, identifiers do not need
-to be unique across your entire application just so long as they are unique within a particular context you're interested
-in, such as a frame and its children. You may use the wxID\_OK identifier, for example, on
-any number of dialogs so long as you don't have several within the same dialog.
-
-If you pass -1 to a window constructor, an identifier will be generated for you, but beware:
-if things don't respond in the way they should, it could be because of an id conflict. It is safer
-to supply window ids at all times. Automatic generation of identifiers starts at 1 so may well conflict
-with your own identifiers.
-
-The following standard identifiers are supplied. You can use wxID\_HIGHEST to determine the
-number above which it is safe to define your own identifiers. Or, you can use identifiers below
-wxID\_LOWEST.
+\index{identifiers}\index{wxID}Window identifiers are integers, and are used to
+uniquely determine window identity in the event system (though you can use it
+for other purposes). In fact, identifiers do not need to be unique
+across your entire application just so long as they are unique within a
+particular context you're interested in, such as a frame and its children. You
+may use the {\tt wxID\_OK} identifier, for example, on any number of dialogs so
+long as you don't have several within the same dialog.
+
+If you pass {\tt wxID\_ANY} to a window constructor, an identifier will be
+generated for you automatically by wxWindows. This is useful when you don't
+care about the exact identifier either because you're not going to process the
+events from the control being created at all or because you process the events
+from all controls in one place (in which case you should specify {\tt wxID\_ANY}
+in the event table or \helpref{wxEvtHandler::Connect}{wxevthandlerconnect} call
+as well. The automatically generated identifiers are always negative and so
+will never conflict with the user-specified identifiers which must be always
+positive.
+
+The following standard identifiers are supplied. You can use wxID\_HIGHEST to
+determine the number above which it is safe to define your own identifiers. Or,
+you can use identifiers below wxID\_LOWEST.
\begin{verbatim}
+#define wxID_ANY -1
+
#define wxID_LOWEST 4999
#define wxID_OPEN 5000
\helpref{wxScrollBar}{wxscrollbar}, \helpref{wxSlider}{wxslider},and \helpref{wxSpinButton}{wxspinbutton}.}
\twocolitem{\helpref{wxSizeEvent}{wxsizeevent}}{The EVT\_SIZE macro is used to handle a window resize.}
\twocolitem{\helpref{wxSplitterEvent}{wxsplitterevent}}{The EVT\_SPLITTER\_SASH\_POS\_CHANGED, EVT\_SPLITTER\_UNSPLIT
-and EVT\_SPLITTER\_DOUBLECLICKED macros are used to handle the various splitter window events.}
+and EVT\_SPLITTER\_DCLICK macros are used to handle the various splitter window events.}
\twocolitem{\helpref{wxSysColourChangedEvent}{wxsyscolourchangedevent}}{The EVT\_SYS\_COLOUR\_CHANGED macro is used to handle
events informing the application that the user has changed the system colours (Windows only).}
\twocolitem{\helpref{wxTreeEvent}{wxtreeevent}}{These macros handle \helpref{wxTreeCtrl}{wxtreectrl} events.}
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