X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/cc6ceca789f584cf3fc3fc17f6da4b7493ca69bd..22188d7396b885721afb6214377a88708910b22b:/include/wx/weakref.h diff --git a/include/wx/weakref.h b/include/wx/weakref.h index 99621fca49..af0a6c0817 100644 --- a/include/wx/weakref.h +++ b/include/wx/weakref.h @@ -13,6 +13,21 @@ #include "wx/tracker.h" + +// Some compilers (VC6, Borland, otehrs?) have problem with template specialization. +// However, this is only used for optimization purposes (a smaller wxWeakRef pointer) +// (and the corner case of wxWeakRef). So for those compilers, we can fall +// back to the non-optimal case, where we use a the same type of weak ref (static one) +// in all cases. See defs.h for various setting these defines depending on compiler. + +#if !defined(HAVE_PARTIAL_SPECIALIZATION) || !defined(HAVE_TEMPLATE_OVERLOAD_RESOLUTION) + #define USE_ONLY_STATIC_WEAKREF +#endif + + +#ifndef USE_ONLY_STATIC_WEAKREF + +// Avoid including this for simpler compilers #include "wx/meta/convertible.h" #include "wx/meta/int2type.h" @@ -22,6 +37,9 @@ struct wxIsStaticTrackable enum { value = wxConvertibleTo::value }; }; +#endif // !USE_ONLY_STATIC_WEAKREF + + // Weak ref implementation when T has wxTrackable as a known base class template class wxWeakRefStatic : public wxTrackerNode @@ -59,7 +77,7 @@ protected: } } - void AssignCopy( const wxWeakRefStatic& wr ) + void AssignCopy(const wxWeakRefStatic& wr) { Assign( wr.m_pobj ); } @@ -74,7 +92,9 @@ protected: T *m_pobj; }; -#ifdef HAVE_PARTIAL_SPECIALIZATION + + +#ifndef USE_ONLY_STATIC_WEAKREF template struct wxWeakRefImpl; @@ -139,7 +159,7 @@ protected: void AssignCopy(const wxWeakRefImpl& wr) { - DoAssign( wr.m_pobj, wr.m_ptbase ); + DoAssign(wr.m_pobj, wr.m_ptbase); } void DoAssign( T* pobj, wxTrackable *ptbase ) { @@ -169,17 +189,18 @@ protected: wxTrackable *m_ptbase; }; -#endif // HAVE_PARTIAL_SPECIALIZATION +#endif // #ifndef USE_ONLY_STATIC_WEAKREF + -// A weak reference to an object of type T, where T has type wxTrackable +// A weak reference to an object of type T, where T has base wxTrackable // (usually statically but if not dynamic_cast<> is tried). template class wxWeakRef : public -#ifdef HAVE_PARTIAL_SPECIALIZATION - wxWeakRefImpl::value> -#else +#ifdef USE_ONLY_STATIC_WEAKREF wxWeakRefStatic +#else + wxWeakRefImpl::value> #endif { public: @@ -194,6 +215,13 @@ public: Assign(pobj); } + // We need this copy ctor, since otherwise a default compiler (binary) copy + // happens (if embedded as an object member). + wxWeakRef(const wxWeakRef& wr) + { + Assign(wr.get()); + } + template wxWeakRef& operator=(TDerived* pobj) { @@ -207,27 +235,22 @@ public: return *this; } - virtual ~wxWeakRef() { Release(); } + virtual ~wxWeakRef() { this->Release(); } // Smart pointer functions - T& operator*() const { return *m_pobj; } - T* operator->() const { return m_pobj; } - - T* get() const { return m_pobj; } + T& operator*() const { return *this->m_pobj; } + T* operator->() const { return this->m_pobj; } - // test for pointer validity: defining conversion to unspecified_bool_type - // and not more obvious bool to avoid implicit conversions to integer types - typedef T *(wxWeakRef::*unspecified_bool_type)() const; - operator unspecified_bool_type() const - { - return this->m_pobj ? &wxWeakRef::get : NULL; - } + T* get() const { return this->m_pobj; } + operator T*() const { return this->m_pobj; } }; +#ifdef HAVE_DYNAMIC_CAST + // Weak ref implementation assign objects are queried for wxTrackable // using dynamic_cast<> -template +template class wxWeakRefDynamic : public wxTrackerNode { public: @@ -238,27 +261,24 @@ public: Assign(pobj); } + wxWeakRefDynamic(const wxWeakRef& wr) + { + Assign(wr.get()); + } + virtual ~wxWeakRefDynamic() { Release(); } // Smart pointer functions - T& operator * (){ wxASSERT(this->m_pobj); return *m_pobj; } - T* operator -> (){ wxASSERT(this->m_pobj); return m_pobj; } - T* operator = (T* pobj) { Assign(pobj); return m_pobj; } - - T* get(){ return this->m_pobj; } - - // operator T* (){ return this->m_pobj; } - - // test for pointer validity: defining conversion to unspecified_bool_type - // and not more obvious bool to avoid implicit conversions to integer types - typedef T *(wxWeakRef::*unspecified_bool_type)() const; - operator unspecified_bool_type() const - { - return m_pobj ? &wxWeakRef::get : NULL; - } + T& operator*() const { wxASSERT(m_pobj); return *m_pobj; } + T* operator->() const { wxASSERT(m_pobj); return m_pobj; } + + T* get() const { return m_pobj; } + operator T* () const { return m_pobj; } + T* operator = (T* pobj) { Assign(pobj); return m_pobj; } + // Assign from another weak ref, point to same object - T* operator = (const wxWeakRef &wr) { Assign( wr.get() ); return this->m_pobj; } + T* operator = (const wxWeakRef &wr) { Assign( wr.get() ); return m_pobj; } void Release() { @@ -300,11 +320,6 @@ protected: } } - void AssignCopy(const wxWeakRefDynamic& wr) - { - Assign(wr.m_pobj); - } - virtual void OnObjectDestroy() { wxASSERT_MSG( m_pobj, "tracked object should have removed us itself" ); @@ -315,9 +330,13 @@ protected: T *m_pobj; }; +#endif // #ifdef HAVE_DYNAMIC_CAST + + // Provide some basic types of weak references class WXDLLIMPEXP_FWD_BASE wxEvtHandler; -class WXDLLIMPEXP_FWD_BASE wxWindow; +class WXDLLIMPEXP_FWD_CORE wxWindow; + typedef wxWeakRef wxEvtHandlerRef; typedef wxWeakRef wxWindowRef;