remove warnings of intentionally unreachable code

[wxWidgets.git] / include / wx / evtloop.h

diff --git a/include/wx/evtloop.h b/include/wx/evtloop.h
index 95e2fce43e26f0e6e63c0c6cec7354812f1d4393..adbb15efa01d128190b5b464f624480ec3878c8d 100644 (file)
--- a/include/wx/evtloop.h
+++ b/include/wx/evtloop.h
@@ -12,37 +12,34 @@
 #ifndef _WX_EVTLOOP_H_
 #define _WX_EVTLOOP_H_
 
 #ifndef _WX_EVTLOOP_H_
 #define _WX_EVTLOOP_H_
 

-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-    #pragma interface "evtloop.h"
-#endif
+#include "wx/utils.h"
+
+class WXDLLEXPORT wxEventLoop;

 
 // ----------------------------------------------------------------------------
 // wxEventLoop: a GUI event loop
 // ----------------------------------------------------------------------------
 
 
 // ----------------------------------------------------------------------------
 // wxEventLoop: a GUI event loop
 // ----------------------------------------------------------------------------
 

-class WXDLLEXPORT wxEventLoop
+class WXDLLEXPORT wxEventLoopBase

 {
 public:
 {
 public:

-    // ctor
-    wxEventLoop() { m_impl = NULL; }
+    // trivial, but needed (because of wxEventLoopBase) ctor
+    wxEventLoopBase() { }

 
     // dtor
 
     // dtor

-    virtual ~wxEventLoop();
+    virtual ~wxEventLoopBase() { }

 
     // start the event loop, return the exit code when it is finished
 
     // start the event loop, return the exit code when it is finished

-    virtual int Run();
+    virtual int Run() = 0;

 
     // exit from the loop with the given exit code
 
     // exit from the loop with the given exit code

-    virtual void Exit(int rc = 0);
+    virtual void Exit(int rc = 0) = 0;

 
 

-    // return TRUE if any events are available
-    virtual bool Pending() const;
-
-    // dispatch a single event, return FALSE if we should exit from the loop
-    virtual bool Dispatch();
+    // return true if any events are available
+    virtual bool Pending() const = 0;

 
 

-    // is the event loop running now?
-    virtual bool IsRunning() const;
+    // dispatch a single event, return false if we should exit from the loop
+    virtual bool Dispatch() = 0;

 
     // return currently active (running) event loop, may be NULL
     static wxEventLoop *GetActive() { return ms_activeLoop; }
 
     // return currently active (running) event loop, may be NULL
     static wxEventLoop *GetActive() { return ms_activeLoop; }


@@ -50,13 +47,155 @@ public:
     // set currently active (running) event loop
     static void SetActive(wxEventLoop* loop) { ms_activeLoop = loop; }
 
     // set currently active (running) event loop
     static void SetActive(wxEventLoop* loop) { ms_activeLoop = loop; }
 

+    // is this event loop running now?
+    //
+    // notice that even if this event loop hasn't terminated yet but has just
+    // spawned a nested (e.g. modal) event loop, this would return false
+    bool IsRunning() const;
+

 protected:
 protected:

-    // the pointer to the port specific implementation class
-    class WXDLLEXPORT wxEventLoopImpl *m_impl;
+    // this function should be called before the event loop terminates, whether
+    // this happens normally (because of Exit() call) or abnormally (because of
+    // an exception thrown from inside the loop)
+    virtual void OnExit() { }
+
+

     // the pointer to currently active loop
     static wxEventLoop *ms_activeLoop;
 
     // the pointer to currently active loop
     static wxEventLoop *ms_activeLoop;
 

+    DECLARE_NO_COPY_CLASS(wxEventLoopBase)
+};
+
+#if defined(__WXMSW__) || defined(__WXMAC__) || defined(__WXDFB__)
+
+// this class can be used to implement a standard event loop logic using
+// Pending() and Dispatch()
+//
+// it also handles idle processing automatically
+class WXDLLEXPORT wxEventLoopManual : public wxEventLoopBase
+{
+public:
+    wxEventLoopManual();
+
+    // enters a loop calling OnNextIteration(), Pending() and Dispatch() and
+    // terminating when Exit() is called
+    virtual int Run();
+
+    // sets the "should exit" flag and wakes up the loop so that it terminates
+    // soon
+    virtual void Exit(int rc = 0);
+
+protected:
+    // implement this to wake up the loop: usually done by posting a dummy event
+    // to it (called from Exit())
+    virtual void WakeUp() = 0;
+
+    // may be overridden to perform some action at the start of each new event
+    // loop iteration
+    virtual void OnNextIteration() { }
+
+
+    // the loop exit code
+    int m_exitcode;
+
+    // should we exit the loop?
+    bool m_shouldExit;
+};
+
+#endif // platforms using "manual" loop
+
+// we're moving away from old m_impl wxEventLoop model as otherwise the user
+// code doesn't have access to platform-specific wxEventLoop methods and this
+// can sometimes be very useful (e.g. under MSW this is necessary for
+// integration with MFC) but currently this is done for MSW only, other ports
+// should follow a.s.a.p.
+#if defined(__WXPALMOS__)
+    #include "wx/palmos/evtloop.h"
+#elif defined(__WXMSW__)
+    #include "wx/msw/evtloop.h"
+#elif defined(__WXMAC__)
+    #include "wx/mac/evtloop.h"
+#elif defined(__WXDFB__)
+    #include "wx/dfb/evtloop.h"
+#else // other platform
+
+class WXDLLEXPORT wxEventLoopImpl;
+
+class WXDLLEXPORT wxEventLoop : public wxEventLoopBase
+{
+public:
+    wxEventLoop() { m_impl = NULL; }
+    virtual ~wxEventLoop();
+
+    virtual int Run();
+    virtual void Exit(int rc = 0);
+    virtual bool Pending() const;
+    virtual bool Dispatch();
+
+protected:
+    // the pointer to the port specific implementation class
+    wxEventLoopImpl *m_impl;
+

     DECLARE_NO_COPY_CLASS(wxEventLoop)
 };
 
     DECLARE_NO_COPY_CLASS(wxEventLoop)
 };
 

+#endif // platforms
+
+inline bool wxEventLoopBase::IsRunning() const { return GetActive() == this; }
+
+// ----------------------------------------------------------------------------
+// wxModalEventLoop
+// ----------------------------------------------------------------------------
+
+// this is a naive generic implementation which uses wxWindowDisabler to
+// implement modality, we will surely need platform-specific implementations
+// too, this generic implementation is here only temporarily to see how it
+// works
+class WXDLLEXPORT wxModalEventLoop : public wxEventLoop
+{
+public:
+    wxModalEventLoop(wxWindow *winModal)
+    {
+        m_windowDisabler = new wxWindowDisabler(winModal);
+    }
+
+protected:
+    virtual void OnExit()
+    {
+        delete m_windowDisabler;
+        m_windowDisabler = NULL;
+
+        wxEventLoop::OnExit();
+    }
+
+private:
+    wxWindowDisabler *m_windowDisabler;
+};
+
+// ----------------------------------------------------------------------------
+// wxEventLoopActivator: helper class for wxEventLoop implementations
+// ----------------------------------------------------------------------------
+
+// this object sets the wxEventLoop given to the ctor as the currently active
+// one and unsets it in its dtor, this is especially useful in presence of
+// exceptions but is more tidy even when we don't use them
+class wxEventLoopActivator
+{
+public:
+    wxEventLoopActivator(wxEventLoop *evtLoop)
+    {
+        m_evtLoopOld = wxEventLoop::GetActive();
+        wxEventLoop::SetActive(evtLoop);
+    }
+
+    ~wxEventLoopActivator()
+    {
+        // restore the previously active event loop
+        wxEventLoop::SetActive(m_evtLoopOld);
+    }
+
+private:
+    wxEventLoop *m_evtLoopOld;
+};
+

 #endif // _WX_EVTLOOP_H_
 #endif // _WX_EVTLOOP_H_