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