src/mgl/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/mgl/evtloop.cpp
   3 // Purpose:     implements wxEventLoop for MGL
   4 // Author:      Vaclav Slavik
   5 // RCS-ID:      $Id$
   6 // Copyright:   (c) 2001-2002 SciTech Software, Inc. (www.scitechsoft.com)
   7 // License:     wxWindows licence
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 // ----------------------------------------------------------------------------
  11 // headers
  12 // ----------------------------------------------------------------------------
  13
  14 // For compilers that support precompilation, includes "wx.h".
  15 #include "wx/wxprec.h"
  16
  17 #ifdef __BORLANDC__
  18     #pragma hdrstop
  19 #endif
  20
  21 #ifndef WX_PRECOMP
  22     #include "wx/window.h"
  23     #include "wx/app.h"
  24     #include "wx/thread.h"
  25     #include "wx/timer.h"
  26 #endif //WX_PRECOMP
  27
  28 #include "wx/evtloop.h"
  29 #include "wx/mgl/private.h"
  30
  31 // ----------------------------------------------------------------------------
  32 // wxEventLoopImpl
  33 // ----------------------------------------------------------------------------
  34
  35 class WXDLLEXPORT wxEventLoopImpl
  36 {
  37 public:
  38     // ctor
  39     wxEventLoopImpl()
  40         {
  41             SetExitCode(0);
  42             SetKeepLooping(true);
  43         }
  44
  45     // process an event
  46     void Dispatch();
  47
  48     // generate an idle event, return true if more idle time requested
  49     bool SendIdleEvent();
  50
  51     // set/get the exit code
  52     void SetExitCode(int exitcode) { m_exitcode = exitcode; }
  53     int GetExitCode() const { return m_exitcode; }
  54
  55     void SetKeepLooping(bool k) { m_keepLooping = k; }
  56     bool GetKeepLooping() const { return m_keepLooping; }
  57
  58 private:
  59
  60     // the exit code of the event loop
  61     int m_exitcode;
  62     // false if the loop should end
  63     bool m_keepLooping;
  64 };
  65
  66 // ============================================================================
  67 // wxEventLoopImpl implementation
  68 // ============================================================================
  69
  70 void wxEventLoopImpl::Dispatch()
  71 {
  72     event_t evt;
  73
  74     // VS: The code bellow is equal to MGL's EVT_halt implementation, with
  75     //     two things added: sleeping (busy waiting is stupid, lets make CPU's
  76     //     life a bit easier) and timers updating
  77
  78     // EVT_halt(&evt, EVT_EVERYEVT);
  79     for (;;)
  80     {
  81 #if wxUSE_TIMER
  82         wxTimer::NotifyTimers();
  83         MGL_wmUpdateDC(g_winMng);
  84 #endif
  85         EVT_pollJoystick();
  86         if ( EVT_getNext(&evt, EVT_EVERYEVT) ) break;
  87         PM_sleep(10);
  88     }
  89     // end of EVT_halt
  90
  91     MGL_wmProcessEvent(g_winMng, &evt);
  92 }
  93
  94 bool wxEventLoopImpl::SendIdleEvent()
  95 {
  96     return wxTheApp->ProcessIdle();
  97 }
  98
  99 // ============================================================================
 100 // wxEventLoop implementation
 101 // ============================================================================
 102
 103 // ----------------------------------------------------------------------------
 104 // wxEventLoop running and exiting
 105 // ----------------------------------------------------------------------------
 106
 107 wxEventLoop::~wxEventLoop()
 108 {
 109     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 110 }
 111
 112 int wxEventLoop::Run()
 113 {
 114     // event loops are not recursive, you need to create another loop!
 115     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 116
 117     m_impl = new wxEventLoopImpl;
 118
 119     wxEventLoopActivator activate(this);
 120
 121     for ( ;; )
 122     {
 123 #if wxUSE_THREADS
 124         //wxMutexGuiLeaveOrEnter(); // FIXME_MGL - huh?
 125 #endif // wxUSE_THREADS
 126
 127         // generate and process idle events for as long as we don't have
 128         // anything else to do
 129         while ( !Pending() && m_impl->SendIdleEvent() ) {}
 130
 131         // a message came or no more idle processing to do, sit in Dispatch()
 132         // waiting for the next message
 133         if ( !Dispatch() )
 134         {
 135             // app terminated
 136             break;
 137         }
 138     }
 139
 140     OnExit();
 141
 142     int exitcode = m_impl->GetExitCode();
 143     delete m_impl;
 144     m_impl = NULL;
 145
 146     return exitcode;
 147 }
 148
 149 void wxEventLoop::Exit(int rc)
 150 {
 151     wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
 152
 153     m_impl->SetExitCode(rc);
 154     m_impl->SetKeepLooping(false);
 155
 156     // Send a dummy event so that the app won't block in EVT_halt if there
 157     // are no user-generated events in the queue:
 158     EVT_post(0, EVT_USEREVT, 0, 0);
 159 }
 160
 161 // ----------------------------------------------------------------------------
 162 // wxEventLoop message processing dispatching
 163 // ----------------------------------------------------------------------------
 164
 165 bool wxEventLoop::Pending() const
 166 {
 167     // update the display here, so that wxYield refreshes display and
 168     // changes take effect immediately, not after emptying events queue:
 169     MGL_wmUpdateDC(g_winMng);
 170
 171     // is there an event in the queue?
 172     event_t evt;
 173     return (bool)(EVT_peekNext(&evt, EVT_EVERYEVT));
 174 }
 175
 176 bool wxEventLoop::Dispatch()
 177 {
 178     wxCHECK_MSG( IsRunning(), false, _T("can't call Dispatch() if not running") );
 179
 180     m_impl->Dispatch();
 181     return m_impl->GetKeepLooping();
 182 }