-/////////////////////////////////////////////////////////////////////////////
-// Name: eventhandling.h
-// Purpose: topic overview
-// Author: wxWidgets team
-// RCS-ID: $Id$
-// Licence: wxWindows license
-/////////////////////////////////////////////////////////////////////////////
-
-/**
-
-@page overview_eventhandling Event Handling
-
-Classes: wxEvtHandler, wxWindow, wxEvent
-
-@li @ref overview_eventhandling_introduction
-@li @ref overview_eventhandling_processing
-@li @ref overview_eventhandling_prog
-@li @ref overview_eventhandling_pluggable
-@li @ref overview_eventhandling_winid
-@li @ref overview_eventhandling_custom
-@li @ref overview_eventhandling_macros
-
-
-<hr>
-
-
-@section overview_eventhandling_introduction Introduction
-
-Before version 2.0 of wxWidgets, events were handled by the application
-either by supplying callback functions, or by overriding virtual member
-functions such as @b OnSize.
-
-From wxWidgets 2.0, @e event tables are used instead, with a few exceptions.
-An event table is placed in an implementation file to tell wxWidgets how to map
-events to member functions. These member functions are not virtual functions, but
-they are all similar in form: they take a single wxEvent-derived argument,
-and have a void return type.
-Here's an example of an event table.
-
-@code
-BEGIN_EVENT_TABLE(MyFrame, wxFrame)
-EVT_MENU(wxID_EXIT, MyFrame::OnExit)
-EVT_MENU(DO_TEST, MyFrame::DoTest)
-EVT_SIZE(MyFrame::OnSize)
-EVT_BUTTON(BUTTON1, MyFrame::OnButton1)
-END_EVENT_TABLE()
-@endcode
-
-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,
-wxSizeEvent is used. For menu commands and most control commands
-(such as button presses), wxCommandEvent is used. When controls get more
-complicated, then specific event classes are used, such as wxTreeEvent for
-events from 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:
-
-@code
-class MyFrame : public wxFrame
-{
-public:
-...
-void OnExit(wxCommandEvent& event);
-void OnSize(wxSizeEvent& event);
-
-protected:
-int m_count;
-...
-
-DECLARE_EVENT_TABLE()
-};
-@endcode
-
-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 wxEvtHandler::Connect to
-connect the events to the handlers dynamically, during run-time. See the
-@ref page_samples_event for an example of doing it.
-
-
-
-@section overview_eventhandling_processing How events are processed
-
-When an event is received from the windowing system, wxWidgets calls
-wxEvtHandler::ProcessEvent on the first
-event handler object belonging to the window generating the event.
-
-It may be noted that wxWidgets' event processing system implements something
-very close to virtual methods in normal C++, i.e. it is possible to alter
-the behaviour of a class by overriding its event handling functions. In
-many cases this works even for changing the behaviour of native controls.
-
-For example it is possible to filter out a number of key events sent by the
-system to a native text control by overriding wxTextCtrl and defining a
-handler for key events using EVT_KEY_DOWN. This would indeed prevent
-any key events from being sent to the native control - which might not be
-what is desired. In this case the event handler function has to call Skip()
-so as to indicate that the search for the event handler should continue.
-
-To summarize, instead of explicitly calling the base class version as you
-would have done with C++ virtual functions (i.e. @e wxTextCtrl::OnChar()),
-you should instead call wxEvent::Skip.
-
-In practice, this would look like this if the derived text control only
-accepts 'a' to 'z' and 'A' to 'Z':
-
-@code
-void MyTextCtrl::OnChar(wxKeyEvent& event)
-{
- if ( isalpha( event.KeyCode() ) )
- {
- // key code is within legal range. we call event.Skip() so the
- // event can be processed either in the base wxWidgets class
- // or the native control.
-
- event.Skip();
- }
- else
- {
- // illegal key hit. we don't call event.Skip() so the
- // event is not processed anywhere else.
-
- wxBell();
- }
-}
-@endcode
-
-The normal order of event table searching by ProcessEvent is as follows:
-
-@li If the object is disabled (via a call to wxEvtHandler::SetEvtHandlerEnabled)
- the function skips to step (6).
-@li If the object is a wxWindow, @b ProcessEvent is recursively called on the window's
- wxValidator. If this returns @true, the function exits.
-@li @b 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.
-@li 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.
-@li If the object is a wxWindow and the event is set to set to propagate (in the library only
- wxCommandEvent based events are set to propagate), @b ProcessEvent is recursively applied
- to the parent window's event handler. If this returns @true, the function exits.
-@li Finally, @b ProcessEvent is called on the wxApp object.
-
-<b>Pay close attention to Step 5</b>. People often overlook or get
-confused by this powerful feature of the wxWidgets event processing
-system. To put it a different way, events set to propagate
-(see wxEvent::ShouldPropagate)
-(most likely derived either directly or indirectly from wxCommandEvent)
-will travel up the containment hierarchy from child to parent until the
-maximal propagation level is reached or an event handler is found that
-doesn't call @c event.Skip().
-
-Finally, there is another additional complication (which, in fact, simplifies
-life of wxWidgets programmers significantly): when propagating the command
-events upwards to the parent window, the event propagation stops when it
-reaches the parent dialog, if any. This means that you don't risk to get
-unexpected events from the dialog controls (which might be left unprocessed by
-the dialog itself because it doesn't care about them) when a modal dialog is
-popped up. The events do propagate beyond the frames, however. The rationale
-for this choice is that there are only a few frames in a typical application
-and their parent-child relation are well understood by the programmer while it
-may be very difficult, if not impossible, to track down all the dialogs which
-may be popped up in a complex program (remember that some are created
-automatically by wxWidgets). If you need to specify a different behaviour for
-some reason, you can use wxWindow::SetExtraStyle(wxWS_EX_BLOCK_EVENTS)
-explicitly to prevent the events from being propagated beyond the given window
-or unset this flag for the dialogs which have it on by default.
-
-Typically events that deal with a window as a window (size, motion,
-paint, mouse, keyboard, etc.) are sent only to the window. Events
-that have a higher level of meaning and/or are generated by the window
-itself, (button click, menu select, tree expand, etc.) are command
-events and are sent up to the parent to see if it is interested in the event.
-
-Note that your application may wish to override ProcessEvent to redirect processing of
-events. This is done in the document/view framework, for example, to allow event handlers
-to be defined in the document or view. To test for command events (which will probably
-be the only events you wish to redirect), you may use wxEvent::IsCommandEvent for efficiency,
-instead of using the slower run-time type system.
-
-As mentioned above, only command events are recursively applied to the parents event
-handler in the library itself. As this quite often causes confusion for users,
-here is a list of system events which will NOT get sent to the parent's event handler:
-
-@li wxEvent: The event base class
-@li wxActivateEvent: A window or application activation event
-@li wxCloseEvent: A close window or end session event
-@li wxEraseEvent: An erase background event
-@li wxFocusEvent: A window focus event
-@li wxKeyEvent: A keypress event
-@li wxIdleEvent: An idle event
-@li wxInitDialogEvent: A dialog initialisation event
-@li wxJoystickEvent: A joystick event
-@li wxMenuEvent: A menu event
-@li wxMouseEvent: A mouse event
-@li wxMoveEvent: A move event
-@li wxPaintEvent: A paint event
-@li wxQueryLayoutInfoEvent: Used to query layout information
-@li wxSetCursorEvent: Used for special cursor processing based on current mouse position
-@li wxSizeEvent: A size event
-@li wxScrollWinEvent: A scroll event sent by a scrolled window (not a scroll bar)
-@li wxSysColourChangedEvent: A system colour change event
-
-In some cases, it might be desired by the programmer to get a certain number
-of system events in a parent window, for example all key events sent to, but not
-used by, the native controls in a dialog. In this case, a special event handler
-will have to be written that will override ProcessEvent() in order to pass
-all events (or any selection of them) to the parent window.
-
-
-@section overview_eventhandling_prog Events generated by the user vs programmatically generated events
-
-While generically wxEvents can be generated both by user
-actions (e.g. resize of a wxWindow) and by calls to functions
-(e.g. wxWindow::SetSize), wxWidgets controls normally send wxCommandEvent-derived
-events only for the user-generated events. The only @b exceptions to this rule are:
-
-@li wxNotebook::AddPage: No event-free alternatives
-@li wxNotebook::AdvanceSelection: No event-free alternatives
-@li wxNotebook::DeletePage: No event-free alternatives
-@li wxNotebook::SetSelection: Use wxNotebook::ChangeSelection instead, as
- wxNotebook::SetSelection is deprecated
-@li wxTreeCtrl::Delete: No event-free alternatives
-@li wxTreeCtrl::DeleteAllItems: No event-free alternatives
-@li wxTreeCtrl::EditLabel: No event-free alternatives
-@li All wxTextCtrl methods
-
-wxTextCtrl::ChangeValue can be used instead of wxTextCtrl::SetValue but the other
-functions, such as wxTextCtrl::Replace or wxTextCtrl::WriteText don't have event-free
-equivalents.
-
-
-
-@section overview_eventhandling_pluggable Pluggable event handlers
-
-In fact, you don't have to derive a new class from a window class
-if you don't want to. You can derive a new class from wxEvtHandler instead,
-defining the appropriate event table, and then call wxWindow::SetEventHandler
-(or, preferably, wxWindow::PushEventHandler) to make this
-event handler the object that responds to events. This way, you can avoid
-a lot of class derivation, and use instances of the same event handler class (but different
-objects as the same event handler object shouldn't be used more than once) to
-handle events from instances of different widget classes.
-
-If you ever have to call a window's event handler
-manually, use the GetEventHandler function to retrieve the window's event handler and use that
-to call the member function. By default, GetEventHandler returns a pointer to the window itself
-unless an application has redirected event handling using SetEventHandler or PushEventHandler.
-
-One use of PushEventHandler is to temporarily or permanently change the
-behaviour of the GUI. For example, you might want to invoke a dialog editor
-in your application that changes aspects of dialog boxes. You can
-grab all the input for an existing dialog box, and edit it 'in situ',
-before restoring its behaviour to normal. So even if the application
-has derived new classes to customize behaviour, your utility can indulge
-in a spot of body-snatching. It could be a useful technique for on-line
-tutorials, too, where you take a user through a serious of steps and
-don't want them to diverge from the lesson. Here, you can examine the events
-coming from buttons and windows, and if acceptable, pass them through to
-the original event handler. Use PushEventHandler/PopEventHandler
-to form a chain of event handlers, where each handler processes a different
-range of events independently from the other handlers.
-
-
-
-@section overview_eventhandling_winid Window identifiers
-
-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 @c 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 @c wxID_ANY to a window constructor, an identifier will be
-generated for you automatically by wxWidgets. 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 @c wxID_ANY
-in the event table or wxEvtHandler::Connect 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.
-
-See @ref page_stdevtid for the list of standard identifiers availabel.
-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.
-Finally, you can allocate identifiers dynamically using wxNewId() function to.
-If you use wxNewId() consistently in your application, you can be sure that
-the your identifiers don't conflict accidentally.
-
-
-@section overview_eventhandling_custom Custom event summary
-
-@subsection overview_eventhandling_custom_general General approach
-
-Since version 2.2.x of wxWidgets, each event type is identified by ID which
-is given to the event type @e at runtime which makes it possible to add
-new event types to the library or application without risking ID clashes
-(two different event types mistakingly getting the same event ID). This
-event type ID is stored in a struct of type @b const wxEventType.
-
-In order to define a new event type, there are principally two choices.
-One is to define a entirely new event class (typically deriving from
-wxEvent or wxCommandEvent.
-
-The other is to use the existing event classes and give them an new event
-type. You'll have to define and declare a new event type using either way,
-and this is done using the following macros:
-
-@code
-// in the header of the source file
-BEGIN_DECLARE_EVENT_TYPES()
-DECLARE_EVENT_TYPE(name, value)
-END_DECLARE_EVENT_TYPES()
-
-// in the implementation
-DEFINE_EVENT_TYPE(name)
-@endcode
-
-You can ignore the @e value parameter of the DECLARE_EVENT_TYPE macro
-since it is used only for backwards compatibility with wxWidgets 2.0.x based
-applications where you have to give the event type ID an explicit value.
-See also the @ref page_samples_event for an example of code
-defining and working with the custom event types.
-
-
-@subsection overview_eventhandling_custom_existing Using existing event classes
-
-If you just want to use a wxCommandEvent with
-a new event type, you can then use one of the generic event table macros
-listed below, without having to define a new macro yourself. This also
-has the advantage that you won't have to define a new wxEvent::Clone()
-method for posting events between threads etc. This could look like this
-in your code:
-
-@code
-DECLARE_EVENT_TYPE(wxEVT_MY_EVENT, -1)
-DEFINE_EVENT_TYPE(wxEVT_MY_EVENT)
-
-// user code intercepting the event
-
-BEGIN_EVENT_TABLE(MyFrame, wxFrame)
-EVT_MENU (wxID_EXIT, MyFrame::OnExit)
-// ....
-EVT_COMMAND (ID_MY_WINDOW, wxEVT_MY_EVENT, MyFrame::OnMyEvent)
-END_EVENT_TABLE()
-
-void MyFrame::OnMyEvent( wxCommandEvent )
-{
- // do something
- wxString text = event.GetText();
-}
-
-
-// user code sending the event
-
-void MyWindow::SendEvent()
-{
- wxCommandEvent event( wxEVT_MY_EVENT, GetId() );
- event.SetEventObject( this );
- // Give it some contents
- event.SetText( wxT("Hallo") );
- // Send it
- GetEventHandler()->ProcessEvent( event );
-}
-@endcode
-
-
-@subsection overview_eventhandling_custom_generic Generic event table macros
-
-@beginTable
-@row2col{EVT_CUSTOM(event\, id\, func),
- Allows you to add a custom event table
- entry by specifying the event identifier (such as wxEVT_SIZE),
- the window identifier, and a member function to call.}
-@row2col{EVT_CUSTOM_RANGE(event\, id1\, id2\, func),
- The same as EVT_CUSTOM, but responds to a range of window identifiers.}
-@row2col{EVT_COMMAND(id\, event\, func),
- The same as EVT_CUSTOM, but expects a member function with a
- wxCommandEvent argument.}
-@row2col{EVT_COMMAND_RANGE(id1\, id2\, event\, func),
- The same as EVT_CUSTOM_RANGE, but
- expects a member function with a wxCommandEvent argument.}
-@row2col{EVT_NOTIFY(event\, id\, func),
- The same as EVT_CUSTOM, but
- expects a member function with a wxNotifyEvent argument.}
-@row2col{EVT_NOTIFY_RANGE(event\, id1\, id2\, func),
- The same as EVT_CUSTOM_RANGE, but
- expects a member function with a wxNotifyEvent argument.}
-@endTable
-
-
-@subsection overview_eventhandling_custom_ownclass Defining your own event class
-
-Under certain circumstances, it will be required to define your own event
-class e.g. for sending more complex data from one place to another. Apart
-from defining your event class, you will also need to define your own
-event table macro (which is quite long). Watch out to put in enough
-casts to the inherited event function. Here is an example:
-
-@code
-// code defining event
-
-class wxPlotEvent: public wxNotifyEvent
-{
-public:
- wxPlotEvent( wxEventType commandType = wxEVT_NULL, int id = 0 );
-
- // accessors
- wxPlotCurve *GetCurve()
- { return m_curve; }
-
- // required for sending with wxPostEvent()
- virtual wxEvent *Clone() const;
-
-private:
- wxPlotCurve *m_curve;
-};
-
-DECLARE_EVENT_TYPE( wxEVT_PLOT_ACTION, -1 )
-
-typedef void (wxEvtHandler::*wxPlotEventFunction)(wxPlotEvent&);
-
-#define EVT_PLOT(id, fn) \
- DECLARE_EVENT_TABLE_ENTRY( wxEVT_PLOT_ACTION, id, -1, \
- (wxObjectEventFunction) (wxEventFunction) (wxCommandEventFunction) (wxNotifyEventFunction) \
- wxStaticCastEvent( wxPlotEventFunction, &fn ), (wxObject *) NULL ),
-
-
-// code implementing the event type and the event class
-
-DEFINE_EVENT_TYPE( wxEVT_PLOT_ACTION )
-
-wxPlotEvent::wxPlotEvent( ...
-
-
-// user code intercepting the event
-
-BEGIN_EVENT_TABLE(MyFrame, wxFrame)
-EVT_PLOT (ID_MY_WINDOW, MyFrame::OnPlot)
-END_EVENT_TABLE()
-
-void MyFrame::OnPlot( wxPlotEvent &event )
-{
- wxPlotCurve *curve = event.GetCurve();
-}
-
-
-// user code sending the event
-
-void MyWindow::SendEvent()
-{
- wxPlotEvent event( wxEVT_PLOT_ACTION, GetId() );
- event.SetEventObject( this );
- event.SetCurve( m_curve );
- GetEventHandler()->ProcessEvent( event );
-}
-@endcode
-
-
-
-
-@section overview_eventhandling_macros Event macros summary
-
-For the full list of event classes, please see the
-@ref page_class_cat_events page.
-
-*/
-
+/////////////////////////////////////////////////////////////////////////////\r
+// Name: eventhandling.h\r
+// Purpose: topic overview\r
+// Author: wxWidgets team\r
+// RCS-ID: $Id$\r
+// Licence: wxWindows license\r
+/////////////////////////////////////////////////////////////////////////////\r
+\r
+/**\r
+\r
+@page overview_events Events and Event Handling\r
+\r
+Related classes: wxEvtHandler, wxWindow, wxEvent\r
+\r
+@li @ref overview_events_introduction\r
+@li @ref overview_events_eventhandling\r
+@li @ref overview_events_processing\r
+@li @ref overview_events_custom\r
+@li @ref overview_events_misc\r
+\r
+\r
+<hr>\r
+\r
+\r
+@section overview_events_introduction Introduction to Events\r
+\r
+Like with all the other GUI frameworks, the control of flow in wxWidgets\r
+applications is event-based: the program normally performs most of its actions\r
+in response to the events generated by the user. These events can be triggered\r
+by using the input devices (such as keyboard, mouse, joystick) directly or,\r
+more commonly, by a standard control which synthesizes such input events into\r
+higher level events: for example, a wxButton can generate a click event when\r
+the user presses the left mouse button on it and then releases it without\r
+pressing @c Esc in the meanwhile. There are also events which don't directly\r
+correspond to the user actions, such as wxTimerEvent or wxSocketEvent.\r
+\r
+But in all cases wxWidgets represents these events in a uniform way and allows\r
+you to handle them in the same way wherever they originate from. And while the\r
+events are normally generated by wxWidgets itself, you can also do this, which\r
+is especially useful when using custom events (see @ref overview_events_custom).\r
+\r
+To be more precise, each event is described by:\r
+ - <em>Event type</em>: this is simply a value of type wxEventType which\r
+ uniquely identifies the type of the event. For example, clicking on a button,\r
+ selecting an item from a list box and pressing a key on the keyboard all\r
+ generate events with different event types.\r
+ - <em>Event class</em> carried by the event: each event has some information\r
+ associated with it and this data is represented by an object of a class\r
+ derived from wxEvent. Events of different types can use the same event class,\r
+ for example both button click and listbox selection events use wxCommandEvent\r
+ class (as do all the other simple control events), but the key press event\r
+ uses wxKeyEvent as the information associated with it is different.\r
+ - <em>Event source</em>: wxEvent stores the object which generated the event\r
+ and, for windows, its identifier (see @ref overview_events_winid). As it is\r
+ common to have more than one object generating events of the same type (e.g. a\r
+ typical window contains several buttons, all generating the same button click\r
+ event), checking the event source object or its id allows to distinguish\r
+ between them.\r
+\r
+\r
+@section overview_events_eventhandling Event Handling\r
+\r
+There are two principal ways to handle events in wxWidgets. One of them uses\r
+<em>event table</em> macros and allows you to define the connection between events\r
+and their handlers only statically, i.e., during program compilation. The other\r
+one uses wxEvtHandler::Connect() call and can be used to connect, and\r
+disconnect, the handlers dynamically, i.e., during run-time depending on some\r
+conditions. It also allows the direct connection of the events of one object to a\r
+handler method in another object. The static event tables can only handle\r
+events in the object where they are defined so using Connect() is more flexible\r
+than using the event tables. On the other hand, event tables are more succinct\r
+and centralize all event handlers connection in one place. You can either\r
+choose a single approach that you find preferable or freely combine both\r
+methods in your program in different classes or even in one and the same class,\r
+although this is probably sufficiently confusing to be a bad idea.\r
+\r
+But before you make this choice, let us discuss these two ways in more\r
+detail. In the next section we provide a short introduction to handling the\r
+events using the event tables. Please see @ref overview_events_connect\r
+for the discussion of Connect().\r
+\r
+@subsection overview_events_eventtables Event Handling with Event Tables\r
+\r
+To use an <em>event table</em> you must first decide in which class you wish to\r
+handle the events. The only requirement imposed by wxWidgets is that this class\r
+must derive from wxEvtHandler and so, considering that wxWindow derives from\r
+it, any classes representing windows can handle events. Simple events such as\r
+menu commands are usually processed at the level of a top-level window\r
+containing the menu, so let's suppose that you need to handle some events in @c\r
+MyFrame class deriving from wxFrame.\r
+\r
+First define one or more <em>event handlers</em>. They\r
+are just simple (non-virtual) methods of the class that take as a parameter a\r
+reference to an object of a wxEvent-derived class and have no return value (any\r
+return information is passed via the argument, which is why it is non-const).\r
+You also need to insert a macro\r
+\r
+@code\r
+DECLARE_EVENT_TABLE()\r
+@endcode\r
+\r
+somewhere in the class declaration. It doesn't matter where it appears but\r
+it's customary to put it at the end because the macro changes the access\r
+type internally so it's safest if nothing follows it. The\r
+full class declaration might look like this:\r
+\r
+@code\r
+class MyFrame : public wxFrame\r
+{\r
+public:\r
+ MyFrame(...) : wxFrame(...) { }\r
+\r
+ ...\r
+\r
+protected:\r
+ int m_whatever;\r
+\r
+private:\r
+ // Notice that as the event handlers normally are not called from outside\r
+ // the class, they normally are private. In particular they don't need\r
+ // to be public.\r
+ void OnExit(wxCommandEvent& event);\r
+ void OnButton1(wxCommandEvent& event);\r
+ void OnSize(wxSizeEvent& event);\r
+\r
+ // it's common to call the event handlers OnSomething() but there is no\r
+ // obligation to do that; this one is an event handler too:\r
+ void DoTest(wxCommandEvent& event);\r
+\r
+ DECLARE_EVENT_TABLE()\r
+};\r
+@endcode\r
+\r
+Next the event table must be defined and, as with any definition, it must be\r
+placed in an implementation file. The event table tells wxWidgets how to map\r
+events to member functions and in our example it could look like this:\r
+\r
+@code\r
+BEGIN_EVENT_TABLE(MyFrame, wxFrame)\r
+ EVT_MENU(wxID_EXIT, MyFrame::OnExit)\r
+ EVT_MENU(DO_TEST, MyFrame::DoTest)\r
+ EVT_SIZE(MyFrame::OnSize)\r
+ EVT_BUTTON(BUTTON1, MyFrame::OnButton1)\r
+END_EVENT_TABLE()\r
+@endcode\r
+\r
+Notice that you must mention a method you want to use for the event handling in\r
+the event table definition; just defining it in MyFrame class is @e not enough.\r
+\r
+Let us now look at the details of this definition: the first line means that we\r
+are defining the event table for MyFrame class and that its base class is\r
+wxFrame, so events not processed by MyFrame will, by default, be handled by\r
+wxFrame. The next four lines define connections of individual events to their\r
+handlers: the first two of them map menu commands from the items with the\r
+identifiers specified as the first macro parameter to two different member\r
+functions. In the next one, @c EVT_SIZE means that any changes in the size of\r
+the frame will result in calling OnSize() method. Note that this macro doesn't\r
+need a window identifier, since normally you are only interested in the current\r
+window's size events.\r
+\r
+The @c EVT_BUTTON macro demonstrates that the originating event does not have to\r
+come from the window class implementing the event table -- if the event source\r
+is a button within a panel within a frame, this will still work, because event\r
+tables are searched up through the hierarchy of windows for the command events.\r
+(But only command events, so you can't catch mouse move events in a child\r
+control in the parent window in the same way because wxMouseEvent doesn't\r
+derive from wxCommandEvent. See below for how you can do it.) In this case, the\r
+button's event table will be searched, then the parent panel's, then the\r
+frame's.\r
+\r
+Finally, you need to implement the event handlers. As mentioned before, all\r
+event handlers take a wxEvent-derived argument whose exact class differs\r
+according to the type of event and the class of the originating window. For\r
+size events, wxSizeEvent is used. For menu commands and most control commands\r
+(such as button presses), wxCommandEvent is used. When controls get more\r
+complicated, more specific wxCommandEvent-derived event classes providing\r
+additional control-specific information can be used, such as wxTreeEvent for\r
+events from wxTreeCtrl windows.\r
+\r
+In the simplest possible case an event handler may not use the @c event\r
+parameter at all. For example,\r
+\r
+@code\r
+void MyFrame::OnExit(wxCommandEvent& WXUNUSED(event))\r
+{\r
+ // when the user selects "Exit" from the menu we should close\r
+ Close(true);\r
+}\r
+@endcode\r
+\r
+In other cases you may need some information carried by the @c event argument,\r
+as in:\r
+\r
+@code\r
+void MyFrame::OnSize(wxSizeEvent& event)\r
+{\r
+ wxSize size = event.GetSize();\r
+\r
+ ... update the frame using the new size ...\r
+}\r
+@endcode\r
+\r
+You will find the details about the event table macros and the corresponding\r
+wxEvent-derived classes in the discussion of each control generating these\r
+events.\r
+\r
+\r
+@subsection overview_events_connect Dynamic Event Handling\r
+\r
+As with the event tables, decide in which class you intend to\r
+handle the events first and, as before, this class must derive from\r
+wxEvtHandler (usually indirectly via wxWindow). See the declaration of MyFrame\r
+in the previous section. However the similarities end here and both the syntax\r
+and the possibilities of handling events in this way are rather different.\r
+\r
+Let us start by looking at the syntax: the first obvious difference is that you\r
+need not use DECLARE_EVENT_TABLE() nor BEGIN_EVENT_TABLE() and the\r
+associated macros. Instead, in any place in your code, but usually in\r
+the code of the class defining the handler itself (and definitely not in the\r
+global scope as with the event tables), call its Connect() method like this:\r
+\r
+@code\r
+MyFrame::MyFrame(...)\r
+{\r
+ Connect(wxID_EXIT, wxEVT_COMMAND_MENU_SELECTED,\r
+ wxCommandEventHandler(MyFrame::OnExit));\r
+}\r
+@endcode\r
+\r
+This class should be self-explanatory except for wxCommandEventHandler part:\r
+this is a macro that ensures that the method is of the correct type by using\r
+static_cast in the same way as the event table macros.\r
+\r
+Now let us describe the semantic differences:\r
+<ul>\r
+ <li>\r
+ Event handlers can be connected at any moment. For example, it's possible\r
+ to do some initialization first and only connect the handlers if and when\r
+ it succeeds. This can avoid the need to test that the object was properly\r
+ initialized in the event handlers themselves. With Connect() they\r
+ simply won't be called if it wasn't correctly initialized.\r
+ </li>\r
+\r
+ <li>\r
+ As a slight extension of the above, the handlers can also be\r
+ Disconnect()-ed at any time and maybe later reconnected. Of course,\r
+ it's also possible to emulate this behaviour with the classic\r
+ static (i.e., connected via event tables) handlers by using an internal\r
+ flag indicating whether the handler is currently enabled and returning\r
+ from it if it isn't, but using dynamically connected handlers requires\r
+ less code and is also usually more clear.\r
+ </li>\r
+\r
+ <li>\r
+ Also notice that you must derive a class inherited from, say,\r
+ wxTextCtrl even if you don't want to modify the control behaviour at\r
+ all but just want to handle some of its events. This is especially\r
+ inconvenient when the control is loaded from the XRC. Connecting the\r
+ event handler dynamically bypasses the need for this unwanted\r
+ sub-classing.\r
+ </li>\r
+\r
+ <li>\r
+ Last but very, very far from least is the possibility to connect an\r
+ event of some object to a method of another object. This is impossible\r
+ to do with event tables because it is not possible to specify the\r
+ object to dispatch the event to so it necessarily needs to be sent to\r
+ the same object which generated the event. Not so with Connect() which\r
+ has an optional @c eventSink parameter that can be used to specify the\r
+ object which will handle the event. Of course, in this case the method\r
+ being connected must belong to the class that is the type of the\r
+ @c eventSink object! To give a quick example, people often want to catch\r
+ mouse movement events happening when the mouse is in one of the frame\r
+ children in the frame itself. Doing it in a naive way doesn't work:\r
+ <ul>\r
+ <li>\r
+ A @c EVT_LEAVE_WINDOW(MyFrame::OnMouseLeave) line in the frame\r
+ event table has no effect as mouse move (including entering and\r
+ leaving) events are not propagated up to the parent window\r
+ (at least not by default).\r
+ </li>\r
+\r
+ <li>\r
+ Putting the same line in a child event table will crash during\r
+ run-time because the MyFrame method will be called on a wrong\r
+ object -- it's easy to convince oneself that the only object\r
+ that can be used here is the pointer to the child, as\r
+ wxWidgets has nothing else. But calling a frame method with the\r
+ child window pointer instead of the pointer to the frame is, of\r
+ course, disastrous.\r
+ </li>\r
+ </ul>\r
+\r
+ However writing\r
+ @code\r
+ MyFrame::MyFrame(...)\r
+ {\r
+ m_child->Connect(wxID_ANY, wxEVT_LEAVE_WINDOW,\r
+ wxMouseEventHandler(MyFrame::OnMouseLeave),\r
+ NULL, // unused extra data parameter\r
+ this); // this indicates the object to connect to\r
+ }\r
+ @endcode\r
+ will work exactly as expected. Note that you can get the object that\r
+ generated the event -- and that is not the same as the frame -- via\r
+ wxEvent::GetEventObject() method of @c event argument passed to the\r
+ event handler.\r
+ </li>\r
+</ul>\r
+\r
+To summarize, using Connect() requires slightly more typing but is much more\r
+flexible than using static event tables so don't hesitate to use it when you\r
+need this extra power. On the other hand, event tables are still perfectly fine\r
+in simple situations where this extra flexibility is not needed.\r
+\r
+\r
+@section overview_events_processing How Events are Processed\r
+\r
+The previous sections explain how to define event handlers but don't address\r
+the question of how exactly wxWidgets finds the handler to call for the\r
+given event. This section describes the algorithm used in detail.\r
+\r
+When an event is received from the windowing system, wxWidgets calls\r
+wxEvtHandler::ProcessEvent() on the first event handler object belonging to the\r
+window generating the event. The normal order of event table searching by\r
+ProcessEvent() is as follows, with the event processing stopping as soon as a\r
+handler is found (unless the handler calls wxEvent::Skip() in which case it\r
+doesn't count as having handled the event and the search continues):\r
+<ol>\r
+ <li value="0">\r
+ Before anything else happens, wxApp::FilterEvent() is called. If it returns\r
+ anything but -1 (default), the event handling stops immediately.\r
+ </li>\r
+\r
+ <li value="1">\r
+ If this event handler is disabled via a call to\r
+ wxEvtHandler::SetEvtHandlerEnabled() the next three steps are skipped and\r
+ the event handler resumes at step (5).\r
+ </li>\r
+\r
+ <li value="2">\r
+ If the object is a wxWindow and has an associated validator, wxValidator\r
+ gets a chance to process the event.\r
+ </li>\r
+\r
+ <li value="3">\r
+ The list of dynamically connected event handlers, i.e., those for which\r
+ Connect() was called, is consulted. Notice that this is done before\r
+ checking the static event table entries, so if both a dynamic and a static\r
+ event handler match the same event, the static one is never going to be\r
+ used.\r
+ </li>\r
+\r
+ <li value="4">\r
+ The event table containing all the handlers defined using the event table\r
+ macros in this class and its base classes is examined. Notice that this\r
+ means that any event handler defined in a base class will be executed at\r
+ this step.\r
+ </li>\r
+\r
+ <li value="5">\r
+ The event is passed to the next event handler, if any, in the event handler\r
+ chain, i.e., the steps (1) to (4) are done for it. This chain can be formed\r
+ using wxEvtHandler::SetNextHandler():\r
+ @image html overview_events_chain.png\r
+ (referring to the image, if @c A->ProcessEvent is called and it doesn't handle\r
+ the event, @c B->ProcessEvent will be called and so on...).\r
+ In the case of wxWindow you can build a stack (implemented using wxEvtHandler\r
+ double-linked list) using wxWindow::PushEventHandler():\r
+ @image html overview_events_winstack.png\r
+ (referring to the image, if @c W->ProcessEvent is called, it immediately calls\r
+ @c A->ProcessEvent; if nor @c A nor @c B handle the event, then the wxWindow\r
+ itself is used - i.e. the dynamically connected event handlers and static\r
+ event table entries of wxWindow are looked as the last possibility, after\r
+ all pushed event handlers were tested).\r
+ Note however that usually there are no wxEvtHandler chains nor wxWindows stacks\r
+ so this step will usually do anything.\r
+ </li>\r
+\r
+ <li value="6">\r
+ If the object is a wxWindow and the event is set to propagate (by default\r
+ only wxCommandEvent-derived events are set to propagate), then the\r
+ processing restarts from the step (1) (and excluding the step (7)) for the\r
+ parent window. If this object is not a window but the next handler exists,\r
+ the event is passed to its parent if it is a window. This ensures that in a\r
+ common case of (possibly several) non-window event handlers pushed on top\r
+ of a window, the event eventually reaches the window parent.\r
+ </li>\r
+\r
+ <li value="7">\r
+ Finally, i.e., if the event is still not processed, the wxApp object itself\r
+ (which derives from wxEvtHandler) gets a last chance to process it.\r
+ </li>\r
+</ol>\r
+\r
+<em>Please pay close attention to step 6!</em> People often overlook or get\r
+confused by this powerful feature of the wxWidgets event processing system. The\r
+details of event propagation up the window hierarchy are described in the\r
+next section.\r
+\r
+Also please notice that there are additional steps in the event handling for\r
+the windows-making part of wxWidgets document-view framework, i.e.,\r
+wxDocParentFrame, wxDocChildFrame and their MDI equivalents wxDocMDIParentFrame\r
+and wxDocMDIChildFrame. The parent frame classes modify step (2) above to\r
+send the events received by them to wxDocManager object first. This object, in\r
+turn, sends the event to the current view and the view itself lets its\r
+associated document process the event first. The child frame classes send\r
+the event directly to the associated view which still forwards it to its\r
+document object. Notice that to avoid remembering the exact order in which the\r
+events are processed in the document-view frame, the simplest, and recommended,\r
+solution is to only handle the events at the view classes level, and not in the\r
+document or document manager classes\r
+\r
+\r
+@subsection overview_events_propagation How Events Propagate Upwards\r
+\r
+As mentioned above, the events of the classes deriving from wxCommandEvent are\r
+propagated by default to the parent window if they are not processed in this\r
+window itself. But although by default only the command events are propagated\r
+like this, other events can be propagated as well because the event handling\r
+code uses wxEvent::ShouldPropagate() to check whether an event should be\r
+propagated. It is also possible to propagate the event only a limited number of\r
+times and not until it is processed (or a top level parent window is reached).\r
+\r
+Finally, there is another additional complication (which, in fact, simplifies\r
+life of wxWidgets programmers significantly): when propagating the command\r
+events up to the parent window, the event propagation stops when it\r
+reaches the parent dialog, if any. This means that you don't risk getting\r
+unexpected events from the dialog controls (which might be left unprocessed by\r
+the dialog itself because it doesn't care about them) when a modal dialog is\r
+popped up. The events do propagate beyond the frames, however. The rationale\r
+for this choice is that there are only a few frames in a typical application\r
+and their parent-child relation are well understood by the programmer while it\r
+may be difficult, if not impossible, to track down all the dialogs that\r
+may be popped up in a complex program (remember that some are created\r
+automatically by wxWidgets). If you need to specify a different behaviour for\r
+some reason, you can use wxWindow::SetExtraStyle(wxWS_EX_BLOCK_EVENTS)\r
+explicitly to prevent the events from being propagated beyond the given window\r
+or unset this flag for the dialogs that have it on by default.\r
+\r
+Typically events that deal with a window as a window (size, motion,\r
+paint, mouse, keyboard, etc.) are sent only to the window. Events\r
+that have a higher level of meaning or are generated by the window\r
+itself (button click, menu select, tree expand, etc.) are command\r
+events and are sent up to the parent to see if it is interested in the event.\r
+More precisely, as said above, all event classes @b not deriving from wxCommandEvent\r
+(see the wxEvent inheritance map) do @b not propagate upward.\r
+\r
+In some cases, it might be desired by the programmer to get a certain number\r
+of system events in a parent window, for example all key events sent to, but not\r
+used by, the native controls in a dialog. In this case, a special event handler\r
+will have to be written that will override ProcessEvent() in order to pass\r
+all events (or any selection of them) to the parent window.\r
+\r
+\r
+@section overview_events_custom Custom Event Summary\r
+\r
+@subsection overview_events_custom_general General approach\r
+\r
+As each event is uniquely defined by its event type, defining a custom event\r
+starts with defining a new event type for it. This is done using\r
+wxDEFINE_EVENT() macro. As an event type is a variable, it can also be\r
+declared using wxDECLARE_EVENT() if necessary.\r
+\r
+The next thing to do is to decide whether you need to define a custom event\r
+class for events of this type or if you can reuse an existing class, typically\r
+either wxEvent (which doesn't provide any extra information) or wxCommandEvent\r
+(which contains several extra fields and also propagates upwards by default).\r
+Both strategies are described in details below. See also the @ref\r
+page_samples_event for a complete example of code defining and working with the\r
+custom event types.\r
+\r
+\r
+@subsection overview_events_custom_existing Using Existing Event Classes\r
+\r
+If you just want to use a wxCommandEvent with a new event type, use one of the\r
+generic event table macros listed below, without having to define a new event\r
+class yourself.\r
+\r
+Example:\r
+\r
+@code\r
+// this is typically in a header: it just declares MY_EVENT event type\r
+wxDECLARE_EVENT(MY_EVENT, wxCommandEvent);\r
+\r
+// this is a definition so can't be in a header\r
+wxDEFINE_EVENT(MY_EVENT, wxCommandEvent);\r
+\r
+// example of code handling the event with event tables\r
+BEGIN_EVENT_TABLE(MyFrame, wxFrame)\r
+ EVT_MENU (wxID_EXIT, MyFrame::OnExit)\r
+ ...\r
+ EVT_COMMAND (ID_MY_WINDOW, MY_EVENT, MyFrame::OnMyEvent)\r
+END_EVENT_TABLE()\r
+\r
+void MyFrame::OnMyEvent(wxCommandEvent& event)\r
+{\r
+ // do something\r
+ wxString text = event.GetText();\r
+}\r
+\r
+// example of code handling the event with Connect():\r
+MyFrame::MyFrame()\r
+{\r
+ Connect(ID_MY_WINDOW, MY_EVENT, &MyFrame::OnMyEvent);\r
+}\r
+\r
+// example of code generating the event\r
+void MyWindow::SendEvent()\r
+{\r
+ wxCommandEvent event(MY_EVENT, GetId());\r
+ event.SetEventObject(this);\r
+\r
+ // Give it some contents\r
+ event.SetText("Hello");\r
+\r
+ // Do send it\r
+ ProcessWindowEvent(event);\r
+}\r
+@endcode\r
+\r
+\r
+@subsection overview_events_custom_ownclass Defining Your Own Event Class\r
+\r
+Under certain circumstances, you must define your own event class e.g., for\r
+sending more complex data from one place to another. Apart from defining your\r
+event class, you also need to define your own event table macro if you want to\r
+use event tables for handling events of this type.\r
+\r
+Here is an example:\r
+\r
+@code\r
+// define a new event class\r
+class MyPlotEvent: public wxEvent\r
+{\r
+public:\r
+ MyPlotEvent(wxEventType eventType, int winid, const wxPoint& pos)\r
+ : wxEvent(winid, eventType),\r
+ m_pos(pos)\r
+ {\r
+ }\r
+\r
+ // accessors\r
+ wxPoint GetPoint() const { return m_pos; }\r
+\r
+ // implement the base class pure virtual\r
+ virtual wxEvent *Clone() const { return new MyPlotEvent(*this); }\r
+\r
+private:\r
+ const wxPoint m_pos;\r
+};\r
+\r
+// we define a single MY_PLOT_CLICKED event type associated with the class\r
+// above but typically you are going to have more than one event type, e.g. you\r
+// could also have MY_PLOT_ZOOMED or MY_PLOT_PANNED &c -- in which case you\r
+// would just add more similar lines here\r
+wxDEFINE_EVENT(MY_PLOT_CLICKED, MyPlotEvent);\r
+\r
+\r
+// if you want to support old compilers you need to use some ugly macros:\r
+typedef void (wxEvtHandler::*MyPlotEventFunction)(MyPlotEvent&);\r
+#define MyPlotEventHandler(func) wxEVENT_HANDLER_CAST(MyPlotEventFunction, func)\r
+\r
+// if your code is only built sing reasonably modern compilers, you could just\r
+// do this instead:\r
+#define MyPlotEventHandler(func) (&func)\r
+\r
+// finally define a macro for creating the event table entries for the new\r
+// event type\r
+//\r
+// remember that you don't need this at all if you only use Connect() and that\r
+// you can replace MyPlotEventHandler(func) with just &func unless you use a\r
+// really old compiler\r
+#define MY_EVT_PLOT_CLICK(id, func) \\r
+ wx__DECLARE_EVT1(MY_PLOT_CLICKED, id, MyPlotEventHandler(func))\r
+\r
+\r
+// example of code handling the event (you will use one of these methods, not\r
+// both, of course):\r
+BEGIN_EVENT_TABLE(MyFrame, wxFrame)\r
+ EVT_PLOT(ID_MY_WINDOW, MyFrame::OnPlot)\r
+END_EVENT_TABLE()\r
+\r
+MyFrame::MyFrame()\r
+{\r
+ Connect(ID_MY_WINDOW, MY_PLOT_CLICKED, &MyFrame::OnPlot);\r
+}\r
+\r
+void MyFrame::OnPlot(MyPlotEvent& event)\r
+{\r
+ ... do something with event.GetPoint() ...\r
+}\r
+\r
+\r
+// example of code generating the event:\r
+void MyWindow::SendEvent()\r
+{\r
+ MyPlotEvent event(MY_PLOT_CLICKED, GetId(), wxPoint(...));\r
+ event.SetEventObject(this);\r
+ ProcessWindowEvent(event);\r
+}\r
+@endcode\r
+\r
+\r
+\r
+@section overview_events_misc Miscellaneous Notes\r
+\r
+@subsection overview_events_virtual Event Handlers vs Virtual Methods\r
+\r
+It may be noted that wxWidgets' event processing system implements something\r
+close to virtual methods in normal C++ in spirit: both of these mechanisms\r
+allow you to alter the behaviour of the base class by defining the event handling\r
+functions in the derived classes.\r
+\r
+There is however an important difference between the two mechanisms when you\r
+want to invoke the default behaviour, as implemented by the base class, from a\r
+derived class handler. With the virtual functions, you need to call the base\r
+class function directly and you can do it either in the beginning of the\r
+derived class handler function (to post-process the event) or at its end (to\r
+pre-process the event). With the event handlers, you only have the option of\r
+pre-processing the events and in order to still let the default behaviour\r
+happen you must call wxEvent::Skip() and @em not call the base class event\r
+handler directly. In fact, the event handler probably doesn't even exist in the\r
+base class as the default behaviour is often implemented in platform-specific\r
+code by the underlying toolkit or OS itself. But even if it does exist at\r
+wxWidgets level, it should never be called directly as the event handlers are\r
+not part of wxWidgets API and should never be called directly.\r
+\r
+Finally, please notice that the event handlers themselves shouldn't be virtual.\r
+They should always be non-virtual and usually private (as there is no need to\r
+make them public) methods of a wxEvtHandler-derived class.\r
+\r
+\r
+@subsection overview_events_prog User Generated Events vs Programmatically Generated Events\r
+\r
+While generically wxEvents can be generated both by user\r
+actions (e.g., resize of a wxWindow) and by calls to functions\r
+(e.g., wxWindow::SetSize), wxWidgets controls normally send wxCommandEvent-derived\r
+events only for the user-generated events. The only @b exceptions to this rule are:\r
+\r
+@li wxNotebook::AddPage: No event-free alternatives\r
+@li wxNotebook::AdvanceSelection: No event-free alternatives\r
+@li wxNotebook::DeletePage: No event-free alternatives\r
+@li wxNotebook::SetSelection: Use wxNotebook::ChangeSelection instead, as\r
+ wxNotebook::SetSelection is deprecated\r
+@li wxTreeCtrl::Delete: No event-free alternatives\r
+@li wxTreeCtrl::DeleteAllItems: No event-free alternatives\r
+@li wxTreeCtrl::EditLabel: No event-free alternatives\r
+@li All wxTextCtrl methods\r
+\r
+wxTextCtrl::ChangeValue can be used instead of wxTextCtrl::SetValue but the other\r
+functions, such as wxTextCtrl::Replace or wxTextCtrl::WriteText don't have event-free\r
+equivalents.\r
+\r
+\r
+\r
+@subsection overview_events_pluggable Pluggable Event Handlers\r
+\r
+<em>TODO: Probably deprecated, Connect() provides a better way to do this</em>\r
+\r
+In fact, you don't have to derive a new class from a window class\r
+if you don't want to. You can derive a new class from wxEvtHandler instead,\r
+defining the appropriate event table, and then call wxWindow::SetEventHandler\r
+(or, preferably, wxWindow::PushEventHandler) to make this\r
+event handler the object that responds to events. This way, you can avoid\r
+a lot of class derivation, and use instances of the same event handler class (but different\r
+objects as the same event handler object shouldn't be used more than once) to\r
+handle events from instances of different widget classes.\r
+\r
+If you ever have to call a window's event handler\r
+manually, use the GetEventHandler function to retrieve the window's event handler and use that\r
+to call the member function. By default, GetEventHandler returns a pointer to the window itself\r
+unless an application has redirected event handling using SetEventHandler or PushEventHandler.\r
+\r
+One use of PushEventHandler is to temporarily or permanently change the\r
+behaviour of the GUI. For example, you might want to invoke a dialog editor\r
+in your application that changes aspects of dialog boxes. You can\r
+grab all the input for an existing dialog box, and edit it 'in situ',\r
+before restoring its behaviour to normal. So even if the application\r
+has derived new classes to customize behaviour, your utility can indulge\r
+in a spot of body-snatching. It could be a useful technique for on-line\r
+tutorials, too, where you take a user through a serious of steps and\r
+don't want them to diverge from the lesson. Here, you can examine the events\r
+coming from buttons and windows, and if acceptable, pass them through to\r
+the original event handler. Use PushEventHandler/PopEventHandler\r
+to form a chain of event handlers, where each handler processes a different\r
+range of events independently from the other handlers.\r
+\r
+\r
+\r
+@subsection overview_events_winid Window Identifiers\r
+\r
+Window identifiers are integers, and are used to\r
+uniquely determine window identity in the event system (though you can use it\r
+for other purposes). In fact, identifiers do not need to be unique\r
+across your entire application as long they are unique within the\r
+particular context you're interested in, such as a frame and its children. You\r
+may use the @c wxID_OK identifier, for example, on any number of dialogs\r
+as long as you don't have several within the same dialog.\r
+\r
+If you pass @c wxID_ANY to a window constructor, an identifier will be\r
+generated for you automatically by wxWidgets. This is useful when you don't\r
+care about the exact identifier either because you're not going to process the\r
+events from the control being created or because you process the events\r
+from all controls in one place (in which case you should specify @c wxID_ANY\r
+in the event table or wxEvtHandler::Connect call\r
+as well). The automatically generated identifiers are always negative and so\r
+will never conflict with the user-specified identifiers which must be always\r
+positive.\r
+\r
+See @ref page_stdevtid for the list of standard identifiers available.\r
+You can use wxID_HIGHEST to determine the number above which it is safe to\r
+define your own identifiers. Or, you can use identifiers below wxID_LOWEST.\r
+Finally, you can allocate identifiers dynamically using wxNewId() function too.\r
+If you use wxNewId() consistently in your application, you can be sure that\r
+your identifiers don't conflict accidentally.\r
+\r
+\r
+@subsection overview_events_custom_generic Generic Event Table Macros\r
+\r
+@beginTable\r
+@row2col{EVT_CUSTOM(event\, id\, func),\r
+ Allows you to add a custom event table\r
+ entry by specifying the event identifier (such as wxEVT_SIZE),\r
+ the window identifier, and a member function to call.}\r
+@row2col{EVT_CUSTOM_RANGE(event\, id1\, id2\, func),\r
+ The same as EVT_CUSTOM, but responds to a range of window identifiers.}\r
+@row2col{EVT_COMMAND(id\, event\, func),\r
+ The same as EVT_CUSTOM, but expects a member function with a\r
+ wxCommandEvent argument.}\r
+@row2col{EVT_COMMAND_RANGE(id1\, id2\, event\, func),\r
+ The same as EVT_CUSTOM_RANGE, but\r
+ expects a member function with a wxCommandEvent argument.}\r
+@row2col{EVT_NOTIFY(event\, id\, func),\r
+ The same as EVT_CUSTOM, but\r
+ expects a member function with a wxNotifyEvent argument.}\r
+@row2col{EVT_NOTIFY_RANGE(event\, id1\, id2\, func),\r
+ The same as EVT_CUSTOM_RANGE, but\r
+ expects a member function with a wxNotifyEvent argument.}\r
+@endTable\r
+\r
+\r
+\r
+@subsection overview_events_list List of wxWidgets events\r
+\r
+For the full list of event classes, please see the\r
+@ref group_class_events "event classes group page".\r
+\r
+\r
+*/\r
+\r
projects / wxWidgets.git / blobdiff