wxWidgets/include/wx/evtloop.h

160 lines
4.7 KiB
C++

///////////////////////////////////////////////////////////////////////////////
// Name: wx/evtloop.h
// Purpose: declares wxEventLoop class
// Author: Vadim Zeitlin
// Modified by:
// Created: 01.06.01
// RCS-ID: $Id$
// Copyright: (c) 2001 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
// Licence: wxWindows licence
///////////////////////////////////////////////////////////////////////////////
#ifndef _WX_EVTLOOP_H_
#define _WX_EVTLOOP_H_
#include "wx/utils.h"
class WXDLLEXPORT wxEventLoop;
// ----------------------------------------------------------------------------
// wxEventLoop: a GUI event loop
// ----------------------------------------------------------------------------
class WXDLLEXPORT wxEventLoopBase
{
public:
// trivial, but needed (because of wxEventLoopBase) ctor
wxEventLoopBase() { }
// dtor
virtual ~wxEventLoopBase() { }
// start the event loop, return the exit code when it is finished
virtual int Run() = 0;
// exit from the loop with the given exit code
virtual void Exit(int rc = 0) = 0;
// return true if any events are available
virtual bool Pending() const = 0;
// 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; }
// 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:
// 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;
DECLARE_NO_COPY_CLASS(wxEventLoopBase)
};
// 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"
#else
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)
};
#endif // __WXMSW__/!__WXMSW__
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_