docs/latex/wx/idleevt.tex

   1 \section{\class{wxIdleEvent}}\label{wxidleevent}
   2
   3 This class is used for idle events, which are generated when the system is idle.
   4
   5 By default, idle events are sent to all windows. If this is causing a significant
   6 overhead in your application, you can call \helpref{wxIdleEvent::SetMode}{wxidleeventsetmode} with
   7 the value wxIDLE\_PROCESS\_SPECIFIED, and set the wxWS\_EX\_PROCESS\_IDLE extra
   8 window style for every window which should receive idle events.
   9
  10 The function \helpref{wxWindow::OnInternalIdle}{wxwindowoninternalidle} is
  11 also provided for internal purposes, and cannot be disabled. wxUpdateUIEvents
  12 are sent from OnInternalIdle.
  13
  14 \wxheading{Derived from}
  15
  16 \helpref{wxEvent}{wxevent}\\
  17 \helpref{wxObject}{wxobject}
  18
  19 \wxheading{Include files}
  20
  21 <wx/event.h>
  22
  23 \wxheading{Event table macros}
  24
  25 To process an idle event, use this event handler macro to direct input to a member
  26 function that takes a wxIdleEvent argument.
  27
  28 \twocolwidtha{7cm}
  29 \begin{twocollist}\itemsep=0pt
  30 \twocolitem{{\bf EVT\_IDLE(func)}}{Process a wxEVT\_IDLE event.}
  31 \end{twocollist}%
  32
  33 \wxheading{Remarks}
  34
  35 Idle events can be caught by the wxApp class, or by top-level window classes.
  36
  37 \wxheading{See also}
  38
  39 \helpref{Event handling overview}{eventhandlingoverview}, \helpref{wxUpdateUIEvent}{wxupdateuievent},
  40 \helpref{wxWindow::OnInternalIdle}{wxwindowoninternalidle}
  41
  42 \latexignore{\rtfignore{\wxheading{Members}}}
  43
  44 \membersection{wxIdleEvent::wxIdleEvent}\label{wxidleeventctor}
  45
  46 \func{}{wxIdleEvent}{\void}
  47
  48 Constructor.
  49
  50 \membersection{wxIdleEvent::CanSend}\label{wxidleeventcansend}
  51
  52 \func{static bool}{CanSend}{\param{wxWindow*}{ window}}
  53
  54 Returns {\tt true} if it is appropriate to send idle events to
  55 this window.
  56
  57 This function looks at the mode used (see \helpref{wxIdleEvent::SetMode}{wxidleeventsetmode}),
  58 and the wxWS\_EX\_PROCESS\_IDLE style in {\it window} to determine whether idle events should be sent to
  59 this window now. By default this will always return {\tt true} because
  60 the update mode is initially wxIDLE\_PROCESS\_ALL. You can change the mode
  61 to only send idle events to windows with the wxWS\_EX\_PROCESS\_IDLE extra window style set.
  62
  63 \wxheading{See also}
  64
  65 \helpref{wxIdleEvent::SetMode}{wxidleeventsetmode}
  66
  67 \membersection{wxIdleEvent::GetMode}\label{wxidleeventgetmode}
  68
  69 \func{static wxIdleMode}{GetMode}{\void}
  70
  71 Static function returning a value specifying how wxWidgets
  72 will send idle events: to all windows, or only to those which specify that they
  73 will process the events.
  74
  75 See \helpref{wxIdleEvent::SetMode}{wxidleeventsetmode}.
  76
  77 \membersection{wxIdleEvent::RequestMore}\label{wxidleeventrequestmore}
  78
  79 \func{void}{RequestMore}{\param{bool}{ needMore = true}}
  80
  81 Tells wxWidgets that more processing is required. This function can be called by an OnIdle
  82 handler for a window or window event handler to indicate that wxApp::OnIdle should
  83 forward the OnIdle event once more to the application windows. If no window calls this function
  84 during OnIdle, then the application will remain in a passive event loop (not calling OnIdle) until a
  85 new event is posted to the application by the windowing system.
  86
  87 \wxheading{See also}
  88
  89 \helpref{wxIdleEvent::MoreRequested}{wxidleeventmorerequested}
  90
  91 \membersection{wxIdleEvent::MoreRequested}\label{wxidleeventmorerequested}
  92
  93 \constfunc{bool}{MoreRequested}{\void}
  94
  95 Returns true if the OnIdle function processing this event requested more processing time.
  96
  97 \wxheading{See also}
  98
  99 \helpref{wxIdleEvent::RequestMore}{wxidleeventrequestmore}
 100
 101 \membersection{wxIdleEvent::SetMode}\label{wxidleeventsetmode}
 102
 103 \func{static void}{SetMode}{\param{wxIdleMode }{mode}}
 104
 105 Static function for specifying how wxWidgets will send idle events: to
 106 all windows, or only to those which specify that they
 107 will process the events.
 108
 109 {\it mode} can be one of the following values.
 110 The default is wxIDLE\_PROCESS\_ALL.
 111
 112 \begin{verbatim}
 113 enum wxIdleMode
 114 {
 115         // Send idle events to all windows
 116     wxIDLE_PROCESS_ALL,
 117
 118         // Send idle events to windows that have
 119         // the wxWS_EX_PROCESS_IDLE flag specified
 120     wxIDLE_PROCESS_SPECIFIED
 121 };
 122 \end{verbatim}
 123