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 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
  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     MGL_wmUpdateDC(g_winMng);
  79
  80     EVT_halt(&evt, EVT_EVERYEVT);
  81     MGL_wmProcessEvent(g_winMng, &evt);
  82 }
  83
  84 bool wxEventLoopImpl::SendIdleEvent()
  85 {
  86     wxIdleEvent event;
  87
  88     return wxTheApp->ProcessEvent(event) && event.MoreRequested();
  89 }
  90
  91 // ============================================================================
  92 // wxEventLoop implementation
  93 // ============================================================================
  94
  95 // ----------------------------------------------------------------------------
  96 // wxEventLoop running and exiting
  97 // ----------------------------------------------------------------------------
  98
  99 wxEventLoop *wxEventLoop::ms_activeLoop = NULL;
 100
 101 wxEventLoop::~wxEventLoop()
 102 {
 103     wxASSERT_MSG( !m_impl, _T("should have been deleted in Run()") );
 104 }
 105
 106 bool wxEventLoop::IsRunning() const
 107 {
 108     return m_impl != NULL;
 109 }
 110
 111 int wxEventLoop::Run()
 112 {
 113     // event loops are not recursive, you need to create another loop!
 114     wxCHECK_MSG( !IsRunning(), -1, _T("can't reenter a message loop") );
 115
 116     m_impl = new wxEventLoopImpl;
 117
 118     wxEventLoop *oldLoop = ms_activeLoop;
 119     ms_activeLoop = 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     int exitcode = m_impl->GetExitCode();
 141     delete m_impl;
 142     m_impl = NULL;
 143
 144     ms_activeLoop = oldLoop;
 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     event_t evt;
 168     return EVT_peekNext(&evt, EVT_EVERYEVT);
 169 }
 170
 171 bool wxEventLoop::Dispatch()
 172 {
 173     wxCHECK_MSG( IsRunning(), FALSE, _T("can't call Dispatch() if not running") );
 174
 175     m_impl->Dispatch();
 176     return m_impl->GetKeepLooping();
 177 }