docs/latex/wx/event.tex

   1 \section{\class{wxEvent}}\label{wxevent}
   2
   3 An event is a structure holding information about an event passed to a
   4 callback or member function. {\bf wxEvent} used to be a multipurpose
   5 event object, and is an abstract base class for other event classes (see below).
   6
   7 For more information about events, see the \helpref{Event handling overview}{eventhandlingoverview}.
   8
   9 \perlnote{In wxPerl custome event classes should be derived from
  10 \texttt{Wx::PlEvent} and \texttt{Wx::PlCommandEvent}.}
  11
  12 \wxheading{Derived from}
  13
  14 \helpref{wxObject}{wxobject}
  15
  16 \wxheading{Include files}
  17
  18 <wx/event.h>
  19
  20 \wxheading{See also}
  21
  22 \helpref{wxCommandEvent}{wxcommandevent},\rtfsp
  23 \helpref{wxMouseEvent}{wxmouseevent}
  24
  25 \latexignore{\rtfignore{\wxheading{Members}}}
  26
  27 \membersection{wxEvent::wxEvent}\label{wxeventctor}
  28
  29 \func{}{wxEvent}{\param{int }{id = 0}, \param{wxEventType }{eventType = {\tt wxEVT\_NULL}}}
  30
  31 Constructor. Should not need to be used directly by an application.
  32
  33 \membersection{wxEvent::m\_eventObject}\label{wxeventmeventobject}
  34
  35 \member{wxObject*}{m\_eventObject}
  36
  37 The object (usually a window) that the event was generated from,
  38 or should be sent to.
  39
  40 \membersection{wxEvent::m\_eventType}\label{wxeventmeventtype}
  41
  42 \member{WXTYPE}{m\_eventType}
  43
  44 The type of the event, such as wxEVENT\_TYPE\_BUTTON\_COMMAND.
  45
  46 \membersection{wxEvent::m\_id}\label{wxeventmid}
  47
  48 \member{int}{m\_id}
  49
  50 Identifier for the window.
  51
  52 \membersection{wxEvent::m\_propagationLevel}\label{wxeventmpropagationlevel}
  53
  54 \member{int}{m\_propagationLevel}
  55
  56 Indicates how many levels the event can propagate. This member is protected and
  57 should typically only be set in the constructors of the derived classes. It
  58 may be temporarily changed by \helpref{StopPropagation}{wxeventstoppropagation}
  59 and \helpref{ResumePropagation}{wxeventresumepropagation} and tested with
  60 \helpref{ShouldPropagate}{wxeventshouldpropagate}.
  61
  62 The initial value is set to either {\tt wxEVENT\_PROPAGATE\_NONE} (by
  63 default) meaning that the event shouldn't be propagated at all or to
  64 {\tt wxEVENT\_PROPAGATE\_MAX} (for command events) meaning that it should be
  65 propagated as much as necessary.
  66
  67 Any positive number means that the event should be propagated but no more than
  68 the given number of times. E.g. the propagation level may be set to $1$ to
  69 propagate the event to its parent only, but not to its grandparent.
  70
  71 \membersection{wxEvent::m\_skipped}\label{wxeventmskipped}
  72
  73 \member{bool}{m\_skipped}
  74
  75 Set to true by {\bf Skip} if this event should be skipped.
  76
  77 \membersection{wxEvent::m\_timeStamp}\label{wxeventmtimestamp}
  78
  79 \member{long}{m\_timeStamp}
  80
  81 Timestamp for this event.
  82
  83 \membersection{wxEvent::Clone}\label{wxeventclone}
  84
  85 \constfunc{virtual wxEvent*}{Clone}{\void}
  86
  87 Returns a copy of the event.
  88
  89 Any event that is posted to the wxWidgets event system for later action (via
  90 \helpref{wxEvtHandler::AddPendingEvent}{wxevthandleraddpendingevent} or
  91 \helpref{wxPostEvent}{wxpostevent}) must implement this method. All wxWidgets
  92 events fully implement this method, but any derived events implemented by the
  93 user should also implement this method just in case they (or some event
  94 derived from them) are ever posted.
  95
  96 All wxWidgets events implement a copy constructor, so the easiest way of
  97 implementing the Clone function is to implement a copy constructor for
  98 a new event (call it MyEvent) and then define the Clone function like this:
  99
 100 \begin{verbatim}
 101     wxEvent *Clone(void) const { return new MyEvent(*this); }
 102 \end{verbatim}
 103
 104 \membersection{wxEvent::GetEventObject}\label{wxeventgeteventobject}
 105
 106 \func{wxObject*}{GetEventObject}{\void}
 107
 108 Returns the object associated with the
 109 event, if any.
 110
 111 \membersection{wxEvent::GetEventType}\label{wxeventgeteventtype}
 112
 113 \func{WXTYPE}{GetEventType}{\void}
 114
 115 Returns the identifier of the given event type,
 116 such as wxEVENT\_TYPE\_BUTTON\_COMMAND.
 117
 118 \membersection{wxEvent::GetId}\label{wxeventgetid}
 119
 120 \constfunc{int}{GetId}{\void}
 121
 122 Returns the identifier associated with this event, such as a button command id.
 123
 124 \membersection{wxEvent::GetSkipped}\label{wxeventgetskipped}
 125
 126 \constfunc{bool}{GetSkipped}{\void}
 127
 128 Returns true if the event handler should be skipped, false otherwise.
 129
 130 \membersection{wxEvent::GetTimestamp}\label{wxeventgettimestamp}
 131
 132 \func{long}{GetTimestamp}{\void}
 133
 134 Gets the timestamp for the event.
 135
 136 \membersection{wxEvent::IsCommandEvent}\label{wxeventiscommandevent}
 137
 138 \constfunc{bool}{IsCommandEvent}{\void}
 139
 140 Returns true if the event is or is derived from
 141 \helpref{wxCommandEvent}{wxcommandevent} else it returns false.
 142 Note: Exists only for optimization purposes.
 143
 144
 145 \membersection{wxEvent::ResumePropagation}\label{wxeventresumepropagation}
 146
 147 \func{void}{ResumePropagation}{\param{int }{propagationLevel}}
 148
 149 Sets the propagation level to the given value (for example returned from an
 150 earlier call to \helpref{StopPropagation}{wxeventstoppropagation}).
 151
 152
 153 \membersection{wxEvent::SetEventObject}\label{wxeventseteventobject}
 154
 155 \func{void}{SetEventObject}{\param{wxObject* }{object}}
 156
 157 Sets the originating object.
 158
 159 \membersection{wxEvent::SetEventType}\label{wxeventseteventtype}
 160
 161 \func{void}{SetEventType}{\param{WXTYPE }{typ}}
 162
 163 Sets the event type.
 164
 165 \membersection{wxEvent::SetId}\label{wxeventsetid}
 166
 167 \func{void}{SetId}{\param{int}{ id}}
 168
 169 Sets the identifier associated with this event, such as a button command id.
 170
 171 \membersection{wxEvent::SetTimestamp}\label{wxeventsettimestamp}
 172
 173 \func{void}{SetTimestamp}{\param{long }{timeStamp}}
 174
 175 Sets the timestamp for the event.
 176
 177 Sets the originating object.
 178
 179 \membersection{wxEvent::ShouldPropagate}\label{wxeventshouldpropagate}
 180
 181 \constfunc{bool}{ShouldPropagate}{\void}
 182
 183 Test if this event should be propagated or not, i.e. if the propagation level
 184 is currently greater than $0$.
 185
 186 \membersection{wxEvent::Skip}\label{wxeventskip}
 187
 188 \func{void}{Skip}{\param{bool}{ skip = true}}
 189
 190 Called by an event handler to tell the event system that the
 191 event handler should be skipped, and the next valid handler used
 192 instead.
 193
 194 \membersection{wxEvent::StopPropagation}\label{wxeventstoppropagation}
 195
 196 \func{int}{StopPropagation}{\void}
 197
 198 Stop the event from propagating to its parent window.
 199
 200 Returns the old propagation level value which may be later passed to
 201 \helpref{ResumePropagation}{wxeventresumepropagation} to allow propagating the
 202 event again.
 203