src/mgl/evtloop.cpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        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 license
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10 // ----------------------------------------------------------------------------
  11 // headers
  12 // ----------------------------------------------------------------------------
  13
  14 #ifdef __GNUG__
  15     #pragma implementation "evtloop.h"
  16 #endif
  17
  18 // For compilers that support precompilation, includes "wx.h".
  19 #include "wx/wxprec.h"
  20
  21 #ifdef __BORLANDC__
  22     #pragma hdrstop
  23 #endif
  24
  25 #ifndef WX_PRECOMP
  26     #include "wx/window.h"
  27     #include "wx/app.h"
  28     #include "wx/thread.h"
  29 #endif //WX_PRECOMP
  30
  31 #include "wx/evtloop.h"
  32 #include "wx/timer.h"
  33 #include "wx/mgl/private.h"
  34
  35 // ----------------------------------------------------------------------------
  36 // wxEventLoopImpl
  37 // ----------------------------------------------------------------------------
  38
  39 class WXDLLEXPORT wxEventLoopImpl
  40 {
  41 public:
  42     // ctor
  43     wxEventLoopImpl()
  44         {
  45             SetExitCode(0);
  46             SetKeepLooping(TRUE);
  47         }
  48
  49     // process an event
  50     void Dispatch();
  51
  52     // generate an idle event, return TRUE if more idle time requested
  53     bool SendIdleEvent();
  54
  55     // set/get the exit code
  56     void SetExitCode(int exitcode) { m_exitcode = exitcode; }
  57     int GetExitCode() const { return m_exitcode; }
  58
  59     void SetKeepLooping(bool k) { m_keepLooping = k; }
  60     bool GetKeepLooping() const { return m_keepLooping; }
  61
  62 private:
  63
  64     // the exit code of the event loop
  65     int m_exitcode;
  66     // FALSE if the loop should end
  67     bool m_keepLooping;
  68 };
  69
  70 // ============================================================================
  71 // wxEventLoopImpl implementation
  72 // ============================================================================
  73
  74 void wxEventLoopImpl::Dispatch()
  75 {
  76     event_t evt;
  77
  78     // VS: The code bellow is equal to MGL's EVT_halt implementation, with
  79     //     two things added: sleeping (busy waiting is stupid, lets make CPU's
  80     //     life a bit easier) and timers updating
  81
  82     // EVT_halt(&evt, EVT_EVERYEVT);
  83     for (;;)
  84     {
  85 #if wxUSE_TIMER
  86         wxTimer::NotifyTimers();
  87         MGL_wmUpdateDC(g_winMng);
  88 #endif
  89         EVT_pollJoystick();
  90         if ( EVT_getNext(&evt, EVT_EVERYEVT) ) break;
  91         PM_sleep(10);
  92     }
  93     // end of EVT_halt
  94
  95     MGL_wmProcessEvent(g_winMng, &evt);
  96 }
  97
  98 bool wxEventLoopImpl::SendIdleEvent()
  99 {
 100     wxIdleEvent event;
 101
 102     return wxTheApp->ProcessEvent(event) && event.MoreRequested();
 103 }
 104
 105 // ============================================================================
 106 // wxEventLoop implementation
 107 // ============================================================================
 108
 109 // ----------------------------------------------------------------------------
 110 // wxEventLoop running and exiting
 111 // ----------------------------------------------------------------------------
 112
 113 wxEventLoop *wxEventLoop::ms_activeLoop = NULL;
 114
 115 wxEventLoop::~wxEventLoop()
 116 {
 117     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 118 }
 119
 120 bool wxEventLoop::IsRunning() const
 121 {
 122     return m_impl != NULL;
 123 }
 124
 125 int wxEventLoop::Run()
 126 {
 127     // event loops are not recursive, you need to create another loop!
 128     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 129
 130     m_impl = new wxEventLoopImpl;
 131
 132     wxEventLoop *oldLoop = ms_activeLoop;
 133     ms_activeLoop = this;
 134
 135     for ( ;; )
 136     {
 137 #if wxUSE_THREADS
 138         //wxMutexGuiLeaveOrEnter(); // FIXME_MGL - huh?
 139 #endif // wxUSE_THREADS
 140
 141         // generate and process idle events for as long as we don't have
 142         // anything else to do
 143         while ( !Pending() && m_impl->SendIdleEvent() ) {}
 144
 145         // a message came or no more idle processing to do, sit in Dispatch()
 146         // waiting for the next message
 147         if ( !Dispatch() )
 148         {
 149             // app terminated
 150             break;
 151         }
 152     }
 153
 154     int exitcode = m_impl->GetExitCode();
 155     delete m_impl;
 156     m_impl = NULL;
 157
 158     ms_activeLoop = oldLoop;
 159
 160     return exitcode;
 161 }
 162
 163 void wxEventLoop::Exit(int rc)
 164 {
 165     wxCHECK_RET( IsRunning(), _T("can't call Exit() if not running") );
 166
 167     m_impl->SetExitCode(rc);
 168     m_impl->SetKeepLooping(FALSE);
 169
 170     // Send a dummy event so that the app won't block in EVT_halt if there
 171     // are no user-generated events in the queue:
 172     EVT_post(0, EVT_USEREVT, 0, 0);
 173 }
 174
 175 // ----------------------------------------------------------------------------
 176 // wxEventLoop message processing dispatching
 177 // ----------------------------------------------------------------------------
 178
 179 bool wxEventLoop::Pending() const
 180 {
 181     // update the display here, so that wxYield refreshes display and
 182     // changes take effect immediately, not after emptying events queue:
 183     MGL_wmUpdateDC(g_winMng);
 184
 185     // is there an event in the queue?
 186     event_t evt;
 187     return EVT_peekNext(&evt, EVT_EVERYEVT);
 188 }
 189
 190 bool wxEventLoop::Dispatch()
 191 {
 192     wxCHECK_MSG( IsRunning(), FALSE, _T("can't call Dispatch() if not running") );
 193
 194     m_impl->Dispatch();
 195     return m_impl->GetKeepLooping();
 196 }