Amebis/wxWidgets
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

A little documentation about custom events as

Browse Source 
per the discussion on the mailing list.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@30859 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
This commit is contained in:
Robert Roebling
2004-12-05 16:30:54 +00:00
parent ade0e73d18
commit 265accbe55
2 changed files with 174 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

182
docs/latex/wx/tevent.tex
View File

@@ -356,21 +356,6 @@ you can use identifiers below wxID\_LOWEST.
\subsection{Event macros summary}\label{eventmacros}
\wxheading{Generic event table macros}
\twocolwidtha{8cm}%
\begin{twocollist}\itemsep=0pt
\twocolitem{\windowstyle{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.}
\twocolitem{\windowstyle{EVT\_CUSTOM\_RANGE(event, id1, id2, func)}}{The same as EVT\_CUSTOM,
but responds to a range of window identifiers.}
\twocolitem{\windowstyle{EVT\_COMMAND(id, event, func)}}{The same as EVT\_CUSTOM, but
expects a member function with a wxCommandEvent argument.}
\twocolitem{\windowstyle{EVT\_COMMAND\_RANGE(id1, id2, event, func)}}{The same as EVT\_CUSTOM\_RANGE, but
expects a member function with a wxCommandEvent argument.}
\end{twocollist}
\wxheading{Macros listed by event class}
The documentation for specific event macros is organised by event class. Please refer
@@ -413,3 +398,170 @@ update pseudo-events, which are generated to give the application the chance to
toolbars and controls.}
\end{twocollist}
\subsection{Custom event summary}\label{customevents}
\wxheading{General approach}
Since version 2.2.x of wxWidgets, each event type is identified by ID which
is given to the event type {\it 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 {\bf 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
\helpref{wxEvent}{wxevent} or \helpref{wxCommandEvent}{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:
\begin{verbatim}
// in the header of the source file
DECLARE_EVENT_TYPE(name, value)
// in the implementation
DEFINE_EVENT_TYPE(name)
\end{verbatim}
You can ignore the {\it value} parameter of the DECLARE\_EVENT\_TYPE macro
since it used only for backwards compatibility with wxWidgets 2.0.x based
applications where you have to give the event type ID an explicit value.
\wxheading{Using existing event classes}
If you just want to use a \helpref{wxCommandEvent}{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 \helpref{wxEvent::Clone()}{wxeventclone}
method for posting events between threads etc. This could look like this
in your code:
{\small%
\begin{verbatim}
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 (wxEVT_MY_EVENT, ID_MY_WINDOW, MyFrame::OnMyEvent)
END_EVENT_TABLE()
void MyFrame::OnMyEvent( wxCommandEvent &event )
{
// 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 );
}
\end{verbatim}
}%
\wxheading{Generic event table macros}
\twocolwidtha{8cm}%
\begin{twocollist}\itemsep=0pt
\twocolitem{\windowstyle{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.}
\twocolitem{\windowstyle{EVT\_CUSTOM\_RANGE(event, id1, id2, func)}}{The same as EVT\_CUSTOM,
but responds to a range of window identifiers.}
\twocolitem{\windowstyle{EVT\_COMMAND(id, event, func)}}{The same as EVT\_CUSTOM, but
expects a member function with a wxCommandEvent argument.}
\twocolitem{\windowstyle{EVT\_COMMAND\_RANGE(id1, id2, event, func)}}{The same as EVT\_CUSTOM\_RANGE, but
expects a member function with a wxCommandEvent argument.}
\twocolitem{\windowstyle{EVT\_NOTIFY(id, event, func)}}{The same as EVT\_CUSTOM, but
expects a member function with a wxNotifyEvent argument.}
\twocolitem{\windowstyle{EVT\_NOTIFY\_RANGE(id1, id2, event, func)}}{The same as EVT\_CUSTOM\_RANGE, but
expects a member function with a wxNotifyEvent argument.}
\end{twocollist}
\wxheading{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, taken mostly
from the {\it wxPlot} library, which is in the {\it contrib} section of
the wxWidgets sources.
{\small%
\begin{verbatim}
// 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()
wxEvent* Clone();
private:
wxPlotCurve *m_curve;
};
DECLARE_EVENT_MACRO( 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 );
}
\end{verbatim}
}%

11
include/wx/event.h
View File

@@ -2427,6 +2427,13 @@ typedef void (wxEvtHandler::*wxMouseCaptureChangedEventFunction)(wxMouseCaptureC
#define EVT_CUSTOM(event, winid, func) DECLARE_EVENT_TABLE_ENTRY( event, winid, wxID_ANY, (wxObjectEventFunction) wxStaticCastEvent( wxEventFunction, & func ), (wxObject *) NULL ),
#define EVT_CUSTOM_RANGE(event, id1, id2, func) DECLARE_EVENT_TABLE_ENTRY( event, id1, id2, (wxObjectEventFunction) wxStaticCastEvent( wxEventFunction, & func ), (wxObject *) NULL ),
// EVT_COMMAND
#define EVT_COMMAND(winid, event, fn) DECLARE_EVENT_TABLE_ENTRY( event, winid, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxCommandEventFunction, & fn ), (wxObject *) NULL ),
#define EVT_COMMAND_RANGE(id1, id2, event, fn) DECLARE_EVENT_TABLE_ENTRY( event, id1, id2, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxCommandEventFunction, & fn ), (wxObject *) NULL ),
#define EVT_NOTIFY(event, winid, func) DECLARE_EVENT_TABLE_ENTRY( event, winid, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) (wxCommandEventFunction) wxStaticCastEvent( wxNotifyFunction, & func ), (wxObject *) NULL ),
#define EVT_NOTIFY_RANGE(event, id1, id2, func) DECLARE_EVENT_TABLE_ENTRY( event, id1, id2, (wxObjectEventFunction) (wxEventFunction) (wxCommandEventFunction) wxStaticCastEvent( wxNotifyFunction, & func ), (wxObject *) NULL ),
// Miscellaneous
#define EVT_SIZE(func) DECLARE_EVENT_TABLE_ENTRY( wxEVT_SIZE, wxID_ANY, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxSizeEventFunction, & func ), (wxObject *) NULL ),
#define EVT_SIZING(func) DECLARE_EVENT_TABLE_ENTRY( wxEVT_SIZING, wxID_ANY, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxSizeEventFunction, & func ), (wxObject *) NULL ),
@@ -2502,10 +2509,6 @@ typedef void (wxEvtHandler::*wxMouseCaptureChangedEventFunction)(wxMouseCaptureC
DECLARE_EVENT_TABLE_ENTRY( wxEVT_LEAVE_WINDOW, wxID_ANY, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxMouseEventFunction, & func ), (wxObject *) NULL ),\
DECLARE_EVENT_TABLE_ENTRY( wxEVT_MOUSEWHEEL, wxID_ANY, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxMouseEventFunction, & func ), (wxObject *) NULL ),
// EVT_COMMAND
#define EVT_COMMAND(winid, event, fn) DECLARE_EVENT_TABLE_ENTRY( event, winid, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxCommandEventFunction, & fn ), (wxObject *) NULL ),
#define EVT_COMMAND_RANGE(id1, id2, event, fn) DECLARE_EVENT_TABLE_ENTRY( event, id1, id2, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxCommandEventFunction, & fn ), (wxObject *) NULL ),
// Scrolling from wxWindow (sent to wxScrolledWindow)
#define EVT_SCROLLWIN(func) \
DECLARE_EVENT_TABLE_ENTRY( wxEVT_SCROLLWIN_TOP, wxID_ANY, wxID_ANY, (wxObjectEventFunction) (wxEventFunction) wxStaticCastEvent( wxScrollWinEventFunction, & func ), (wxObject *) NULL ),\