// Whether we're using the current theme for this window (wxGTK only for now)
m_themeEnabled = false;
- // VZ: this one shouldn't exist...
+ // This is set to true by SendDestroyEvent() which should be called by the
+ // most derived class to ensure that the destruction event is sent as soon
+ // as possible to allow its handlers to still see the undestroyed window
m_isBeingDeleted = false;
m_freezeCount = 0;
void wxWindowBase::SendDestroyEvent()
{
+ if ( m_isBeingDeleted )
+ {
+ // we could have been already called from a more derived class dtor,
+ // e.g. ~wxTLW calls us and so does ~wxWindow and the latter call
+ // should be simply ignored
+ return;
+ }
+
+ m_isBeingDeleted = true;
+
wxWindowDestroyEvent event;
event.SetEventObject(this);
event.SetId(GetId());
bool wxWindowBase::Destroy()
{
+ SendDestroyEvent();
+
delete this;
return true;
wxWindow *child = node->GetData();
- // note that we really want to call delete and not ->Destroy() here
- // because we want to delete the child immediately, before we are
- // deleted, and delayed deletion would result in problems as our (top
- // level) child could outlive its parent
- delete child;
+ // note that we really want to delete it immediately so don't call the
+ // possible overridden Destroy() version which might not delete the
+ // child immediately resulting in problems with our (top level) child
+ // outliving its parent
+ child->wxWindowBase::Destroy();
wxASSERT_MSG( !GetChildren().Find(child),
wxT("child didn't remove itself using RemoveChild()") );
// event handler stuff
// ----------------------------------------------------------------------------
-void wxWindowBase::PushEventHandler(wxEvtHandler *handler)
+void wxWindowBase::SetEventHandler(wxEvtHandler *handler)
{
+ wxCHECK_RET(handler != NULL, "SetEventHandler(NULL) called");
+
+ m_eventHandler = handler;
+}
+
+void wxWindowBase::SetNextHandler(wxEvtHandler *WXUNUSED(handler))
+{
+ // disable wxEvtHandler chain mechanism for wxWindows:
+ // wxWindow uses its own stack mechanism which doesn't mix well with wxEvtHandler's one
+
+ wxFAIL_MSG("wxWindow cannot be part of a wxEvtHandler chain");
+}
+void wxWindowBase::SetPreviousHandler(wxEvtHandler *WXUNUSED(handler))
+{
+ // we can't simply wxFAIL here as in SetNextHandler: in fact the last
+ // handler of our stack when is destroyed will be Unlink()ed and thus
+ // will call this function to update the pointer of this window...
+
+ //wxFAIL_MSG("wxWindow cannot be part of a wxEvtHandler chain");
+}
+
+void wxWindowBase::PushEventHandler(wxEvtHandler *handlerToPush)
+{
+ wxCHECK_RET( handlerToPush != NULL, "PushEventHandler(NULL) called" );
+
+ // the new handler is going to be part of the wxWindow stack of event handlers:
+ // it can't be part also of an event handler double-linked chain:
+ wxASSERT_MSG(handlerToPush->IsUnlinked(),
+ "The handler being pushed in the wxWindow stack shouldn't be part of "
+ "a wxEvtHandler chain; call Unlink() on it first");
+
wxEvtHandler *handlerOld = GetEventHandler();
+ wxCHECK_RET( handlerOld, "an old event handler is NULL?" );
- handler->SetNextHandler(handlerOld);
+ // now use wxEvtHandler double-linked list to implement a stack:
+ handlerToPush->SetNextHandler(handlerOld);
- if ( handlerOld )
- GetEventHandler()->SetPreviousHandler(handler);
+ if (handlerOld != this)
+ handlerOld->SetPreviousHandler(handlerToPush);
- SetEventHandler(handler);
+ SetEventHandler(handlerToPush);
+
+#ifdef __WXDEBUG__
+ // final checks of the operations done above:
+ wxASSERT_MSG( handlerToPush->GetPreviousHandler() == NULL,
+ "the first handler of the wxWindow stack should have no previous handlers set" );
+ wxASSERT_MSG( handlerToPush->GetNextHandler() != NULL,
+ "the first handler of the wxWindow stack should have non-NULL next handler" );
+
+ wxEvtHandler* pLast = handlerToPush;
+ while (pLast && pLast != this)
+ pLast = pLast->GetNextHandler();
+ wxASSERT_MSG( pLast->GetNextHandler() == NULL,
+ "the last handler of the wxWindow stack should have this window as next handler" );
+#endif
}
wxEvtHandler *wxWindowBase::PopEventHandler(bool deleteHandler)
{
- wxEvtHandler *handlerA = GetEventHandler();
- if ( handlerA )
- {
- wxEvtHandler *handlerB = handlerA->GetNextHandler();
- handlerA->SetNextHandler(NULL);
+ // we need to pop the wxWindow stack, i.e. we need to remove the first handler
- if ( handlerB )
- handlerB->SetPreviousHandler(NULL);
- SetEventHandler(handlerB);
+ wxEvtHandler *firstHandler = GetEventHandler();
+ wxCHECK_MSG( firstHandler != NULL, NULL, "wxWindow cannot have a NULL event handler" );
+ wxCHECK_MSG( firstHandler != this, NULL, "cannot pop the wxWindow itself" );
+ wxCHECK_MSG( firstHandler->GetPreviousHandler() == NULL, NULL,
+ "the first handler of the wxWindow stack should have no previous handlers set" );
- if ( deleteHandler )
- {
- delete handlerA;
- handlerA = NULL;
- }
+ wxEvtHandler *secondHandler = firstHandler->GetNextHandler();
+ wxCHECK_MSG( secondHandler != NULL, NULL,
+ "the first handler of the wxWindow stack should have non-NULL next handler" );
+
+ firstHandler->SetNextHandler(NULL);
+ secondHandler->SetPreviousHandler(NULL);
+
+ // now firstHandler is completely unlinked; set secondHandler as the new window event handler
+ SetEventHandler(secondHandler);
+
+ if ( deleteHandler )
+ {
+ delete firstHandler;
+ firstHandler = NULL;
}
- return handlerA;
+ return firstHandler;
}
-bool wxWindowBase::RemoveEventHandler(wxEvtHandler *handler)
+bool wxWindowBase::RemoveEventHandler(wxEvtHandler *handlerToRemove)
{
- wxCHECK_MSG( handler, false, _T("RemoveEventHandler(NULL) called") );
+ wxCHECK_MSG( handlerToRemove != NULL, false, "RemoveEventHandler(NULL) called" );
+ wxCHECK_MSG( handlerToRemove != this, false, "Cannot remove the window itself" );
- wxEvtHandler *handlerPrev = NULL,
- *handlerCur = GetEventHandler();
- while ( handlerCur )
+ if (handlerToRemove == GetEventHandler())
+ {
+ // removing the first event handler is equivalent to "popping" the stack
+ PopEventHandler(false);
+ return true;
+ }
+
+ // NOTE: the wxWindow event handler list is always terminated with "this" handler
+ wxEvtHandler *handlerCur = GetEventHandler()->GetNextHandler();
+ while ( handlerCur != this )
{
wxEvtHandler *handlerNext = handlerCur->GetNextHandler();
- if ( handlerCur == handler )
+ if ( handlerCur == handlerToRemove )
{
- if ( handlerPrev )
- {
- handlerPrev->SetNextHandler(handlerNext);
- }
- else
- {
- SetEventHandler(handlerNext);
- }
-
- if ( handlerNext )
- {
- handlerNext->SetPreviousHandler ( handlerPrev );
- }
-
- handler->SetNextHandler(NULL);
- handler->SetPreviousHandler(NULL);
+ handlerCur->Unlink();
+ wxASSERT_MSG( handlerCur != GetEventHandler(),
+ "the case Remove == Pop should was already handled" );
return true;
}
- handlerPrev = handlerCur;
handlerCur = handlerNext;
}
bool wxWindowBase::HandleWindowEvent(wxEvent& event) const
{
+ // SafelyProcessEvent() will handle exceptions nicely
return GetEventHandler()->SafelyProcessEvent(event);
}
projects / wxWidgets.git / blobdiff