| 1 | /////////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: src/common/evtloopcmn.cpp |
| 3 | // Purpose: common wxEventLoop-related stuff |
| 4 | // Author: Vadim Zeitlin |
| 5 | // Modified by: |
| 6 | // Created: 2006-01-12 |
| 7 | // RCS-ID: $Id$ |
| 8 | // Copyright: (c) 2006 Vadim Zeitlin <vadim@wxwindows.org> |
| 9 | // Licence: wxWindows licence |
| 10 | /////////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | // for compilers that support precompilation, includes "wx.h". |
| 13 | #include "wx/wxprec.h" |
| 14 | |
| 15 | #ifdef __BORLANDC__ |
| 16 | #pragma hdrstop |
| 17 | #endif |
| 18 | |
| 19 | #include "wx/evtloop.h" |
| 20 | |
| 21 | #ifndef WX_PRECOMP |
| 22 | #include "wx/app.h" |
| 23 | #endif //WX_PRECOMP |
| 24 | |
| 25 | // ---------------------------------------------------------------------------- |
| 26 | // wxEventLoopBase |
| 27 | // ---------------------------------------------------------------------------- |
| 28 | |
| 29 | wxEventLoopBase *wxEventLoopBase::ms_activeLoop = NULL; |
| 30 | |
| 31 | wxEventLoopBase::wxEventLoopBase() |
| 32 | { |
| 33 | m_isInsideYield = false; |
| 34 | m_eventsToProcessInsideYield = wxEVT_CATEGORY_ALL; |
| 35 | } |
| 36 | |
| 37 | bool wxEventLoopBase::IsMain() const |
| 38 | { |
| 39 | if (wxTheApp) |
| 40 | return wxTheApp->GetMainLoop() == this; |
| 41 | return false; |
| 42 | } |
| 43 | |
| 44 | /* static */ |
| 45 | void wxEventLoopBase::SetActive(wxEventLoopBase* loop) |
| 46 | { |
| 47 | ms_activeLoop = loop; |
| 48 | |
| 49 | if (wxTheApp) |
| 50 | wxTheApp->OnEventLoopEnter(loop); |
| 51 | } |
| 52 | |
| 53 | void wxEventLoopBase::OnExit() |
| 54 | { |
| 55 | if (wxTheApp) |
| 56 | wxTheApp->OnEventLoopExit(this); |
| 57 | } |
| 58 | |
| 59 | void wxEventLoopBase::WakeUpIdle() |
| 60 | { |
| 61 | WakeUp(); |
| 62 | } |
| 63 | |
| 64 | bool wxEventLoopBase::ProcessIdle() |
| 65 | { |
| 66 | return wxTheApp && wxTheApp->ProcessIdle(); |
| 67 | } |
| 68 | |
| 69 | bool wxEventLoopBase::Yield(bool onlyIfNeeded) |
| 70 | { |
| 71 | if ( m_isInsideYield ) |
| 72 | { |
| 73 | if ( !onlyIfNeeded ) |
| 74 | { |
| 75 | wxFAIL_MSG( wxT("wxYield called recursively" ) ); |
| 76 | } |
| 77 | |
| 78 | return false; |
| 79 | } |
| 80 | |
| 81 | return YieldFor(wxEVT_CATEGORY_ALL); |
| 82 | } |
| 83 | |
| 84 | // wxEventLoopManual is unused in the other ports |
| 85 | #if defined(__WXMSW__) || defined(__WXDFB__) || ( ( defined(__UNIX__) && !defined(__WXOSX__) ) && wxUSE_BASE) |
| 86 | |
| 87 | // ============================================================================ |
| 88 | // wxEventLoopManual implementation |
| 89 | // ============================================================================ |
| 90 | |
| 91 | wxEventLoopManual::wxEventLoopManual() |
| 92 | { |
| 93 | m_exitcode = 0; |
| 94 | m_shouldExit = false; |
| 95 | } |
| 96 | |
| 97 | bool wxEventLoopManual::ProcessEvents() |
| 98 | { |
| 99 | // process pending wx events first as they correspond to low-level events |
| 100 | // which happened before, i.e. typically pending events were queued by a |
| 101 | // previous call to Dispatch() and if we didn't process them now the next |
| 102 | // call to it might enqueue them again (as happens with e.g. socket events |
| 103 | // which would be generated as long as there is input available on socket |
| 104 | // and this input is only removed from it when pending event handlers are |
| 105 | // executed) |
| 106 | if ( wxTheApp ) |
| 107 | wxTheApp->ProcessPendingEvents(); |
| 108 | |
| 109 | return Dispatch(); |
| 110 | } |
| 111 | |
| 112 | int wxEventLoopManual::Run() |
| 113 | { |
| 114 | // event loops are not recursive, you need to create another loop! |
| 115 | wxCHECK_MSG( !IsRunning(), -1, wxT("can't reenter a message loop") ); |
| 116 | |
| 117 | // ProcessIdle() and ProcessEvents() below may throw so the code here should |
| 118 | // be exception-safe, hence we must use local objects for all actions we |
| 119 | // should undo |
| 120 | wxEventLoopActivator activate(this); |
| 121 | |
| 122 | // we must ensure that OnExit() is called even if an exception is thrown |
| 123 | // from inside ProcessEvents() but we must call it from Exit() in normal |
| 124 | // situations because it is supposed to be called synchronously, |
| 125 | // wxModalEventLoop depends on this (so we can't just use ON_BLOCK_EXIT or |
| 126 | // something similar here) |
| 127 | #if wxUSE_EXCEPTIONS |
| 128 | for ( ;; ) |
| 129 | { |
| 130 | try |
| 131 | { |
| 132 | #endif // wxUSE_EXCEPTIONS |
| 133 | |
| 134 | // this is the event loop itself |
| 135 | for ( ;; ) |
| 136 | { |
| 137 | // give them the possibility to do whatever they want |
| 138 | OnNextIteration(); |
| 139 | |
| 140 | // generate and process idle events for as long as we don't |
| 141 | // have anything else to do |
| 142 | while ( !Pending() && ProcessIdle() && !m_shouldExit ) |
| 143 | ; |
| 144 | |
| 145 | // if the "should exit" flag is set, the loop should terminate |
| 146 | // but not before processing any remaining messages so while |
| 147 | // Pending() returns true, do process them |
| 148 | if ( m_shouldExit ) |
| 149 | { |
| 150 | while ( Pending() ) |
| 151 | ProcessEvents(); |
| 152 | |
| 153 | break; |
| 154 | } |
| 155 | |
| 156 | // a message came or no more idle processing to do, dispatch |
| 157 | // all the pending events and call Dispatch() to wait for the |
| 158 | // next message |
| 159 | if ( !ProcessEvents() ) |
| 160 | { |
| 161 | // we got WM_QUIT |
| 162 | break; |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | #if wxUSE_EXCEPTIONS |
| 167 | // exit the outer loop as well |
| 168 | break; |
| 169 | } |
| 170 | catch ( ... ) |
| 171 | { |
| 172 | try |
| 173 | { |
| 174 | if ( !wxTheApp || !wxTheApp->OnExceptionInMainLoop() ) |
| 175 | { |
| 176 | OnExit(); |
| 177 | break; |
| 178 | } |
| 179 | //else: continue running the event loop |
| 180 | } |
| 181 | catch ( ... ) |
| 182 | { |
| 183 | // OnException() throwed, possibly rethrowing the same |
| 184 | // exception again: very good, but we still need OnExit() to |
| 185 | // be called |
| 186 | OnExit(); |
| 187 | throw; |
| 188 | } |
| 189 | } |
| 190 | } |
| 191 | #endif // wxUSE_EXCEPTIONS |
| 192 | |
| 193 | return m_exitcode; |
| 194 | } |
| 195 | |
| 196 | void wxEventLoopManual::Exit(int rc) |
| 197 | { |
| 198 | wxCHECK_RET( IsRunning(), wxT("can't call Exit() if not running") ); |
| 199 | |
| 200 | m_exitcode = rc; |
| 201 | m_shouldExit = true; |
| 202 | |
| 203 | OnExit(); |
| 204 | |
| 205 | // all we have to do to exit from the loop is to (maybe) wake it up so that |
| 206 | // it can notice that Exit() had been called |
| 207 | // |
| 208 | // in particular, do *not* use here calls such as PostQuitMessage() (under |
| 209 | // MSW) which terminate the current event loop here because we're not sure |
| 210 | // that it is going to be processed by the correct event loop: it would be |
| 211 | // possible that another one is started and terminated by mistake if we do |
| 212 | // this |
| 213 | WakeUp(); |
| 214 | } |
| 215 | |
| 216 | #endif // __WXMSW__ || __WXMAC__ || __WXDFB__ |
| 217 | |