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