include/wx/evtloop.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/evtloop.h
   3 // Purpose:     declares wxEventLoop class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     01.06.01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_EVTLOOP_H_
  13 #define _WX_EVTLOOP_H_
  14
  15 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  16     #pragma interface "evtloop.h"
  17 #endif
  18
  19 #include "wx/utils.h"
  20
  21 class WXDLLEXPORT wxEventLoop;
  22
  23 // ----------------------------------------------------------------------------
  24 // wxEventLoop: a GUI event loop
  25 // ----------------------------------------------------------------------------
  26
  27 class WXDLLEXPORT wxEventLoopBase
  28 {
  29 public:
  30     // trivial, but needed (because of wxEventLoopBase) ctor
  31     wxEventLoopBase() { }
  32
  33     // dtor
  34     virtual ~wxEventLoopBase() { }
  35
  36     // start the event loop, return the exit code when it is finished
  37     virtual int Run() = 0;
  38
  39     // exit from the loop with the given exit code
  40     virtual void Exit(int rc = 0) = 0;
  41
  42     // return true if any events are available
  43     virtual bool Pending() const = 0;
  44
  45     // dispatch a single event, return false if we should exit from the loop
  46     virtual bool Dispatch() = 0;
  47
  48     // is the event loop running now?
  49     virtual bool IsRunning() const = 0;
  50
  51     // return currently active (running) event loop, may be NULL
  52     static wxEventLoop *GetActive() { return ms_activeLoop; }
  53
  54     // set currently active (running) event loop
  55     static void SetActive(wxEventLoop* loop) { ms_activeLoop = loop; }
  56
  57 protected:
  58     // this function should be called before the event loop terminates, whether
  59     // this happens normally (because of Exit() call) or abnormally (because of
  60     // an exception thrown from inside the loop)
  61     virtual void OnExit() { }
  62
  63
  64     // the pointer to currently active loop
  65     static wxEventLoop *ms_activeLoop;
  66
  67     DECLARE_NO_COPY_CLASS(wxEventLoopBase)
  68 };
  69
  70 // we're moving away from old m_impl wxEventLoop model as otherwise the user
  71 // code doesn't have access to platform-specific wxEventLoop methods and this
  72 // can sometimes be very useful (e.g. under MSW this is necessary for
  73 // integration with MFC) but currently this is done for MSW only, other ports
  74 // should follow a.s.a.p.
  75 #ifdef __WXMSW__
  76     #include "wx/msw/evtloop.h"
  77 #else
  78
  79 class WXDLLEXPORT wxEventLoopImpl;
  80
  81 class WXDLLEXPORT wxEventLoop : public wxEventLoopBase
  82 {
  83 public:
  84     wxEventLoop() { m_impl = NULL; }
  85     virtual ~wxEventLoop();
  86
  87     virtual int Run();
  88     virtual void Exit(int rc = 0);
  89     virtual bool Pending() const;
  90     virtual bool Dispatch();
  91     virtual bool IsRunning() const { return m_impl != NULL; }
  92
  93 protected:
  94     // the pointer to the port specific implementation class
  95     wxEventLoopImpl *m_impl;
  96
  97     DECLARE_NO_COPY_CLASS(wxEventLoop)
  98         };
  99
 100 #endif // __WXMSW__/!__WXMSW__
 101
 102 // ----------------------------------------------------------------------------
 103 // wxModalEventLoop
 104 // ----------------------------------------------------------------------------
 105
 106 // this is a naive generic implementation which uses wxWindowDisabler to
 107 // implement modality, we will surely need platform-specific implementations
 108 // too, this generic implementation is here only temporarily to see how it
 109 // works
 110 class WXDLLEXPORT wxModalEventLoop : public wxEventLoop
 111 {
 112 public:
 113     wxModalEventLoop(wxWindow *winModal)
 114     {
 115         m_windowDisabler = new wxWindowDisabler(winModal);
 116     }
 117
 118 protected:
 119     virtual void OnExit()
 120     {
 121         delete m_windowDisabler;
 122         m_windowDisabler = NULL;
 123
 124         wxEventLoop::OnExit();
 125     }
 126
 127 private:
 128     wxWindowDisabler *m_windowDisabler;
 129 };
 130
 131 #endif // _WX_EVTLOOP_H_