From 349efbaa89b499557d9a26320bcbd9b012aac9d2 Mon Sep 17 00:00:00 2001 From: Vadim Zeitlin Date: Mon, 13 Aug 2001 15:42:29 +0000 Subject: [PATCH] implemented (untested) work around for wxScrolledWindow painting bug git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@11369 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775 --- include/wx/generic/scrolwin.h | 6 ++ include/wx/scrolwin.h | 10 +++ src/generic/scrlwing.cpp | 117 +++++++++++++++++++++++++--------- 3 files changed, 104 insertions(+), 29 deletions(-) diff --git a/include/wx/generic/scrolwin.h b/include/wx/generic/scrolwin.h index a8f180e034..ecf2c8fa26 100644 --- a/include/wx/generic/scrolwin.h +++ b/include/wx/generic/scrolwin.h @@ -66,8 +66,14 @@ class WXDLLEXPORT wxGenericScrolledWindow : public wxPanel, virtual void PrepareDC(wxDC& dc) { DoPrepareDC(dc); } +protected: + // this is needed for wxEVT_PAINT processing hack described in + // wxScrollHelperEvtHandler::ProcessEvent() + void OnPaint(wxPaintEvent& event); + private: DECLARE_ABSTRACT_CLASS(wxGenericScrolledWindow) + DECLARE_EVENT_TABLE() }; #ifdef __VISUALC__ diff --git a/include/wx/scrolwin.h b/include/wx/scrolwin.h index c85b28e568..2f955eaea7 100644 --- a/include/wx/scrolwin.h +++ b/include/wx/scrolwin.h @@ -14,6 +14,7 @@ #include "wx/window.h" +class WXDLLEXPORT wxScrollHelperEvtHandler; class WXDLLEXPORT wxTimer; // ---------------------------------------------------------------------------- @@ -139,6 +140,13 @@ protected: *h = size.y; } + // change just the target window (unlike SetWindow which changes m_win as + // well) + void DoSetTargetWindow(wxWindow *target); + + // delete the event handler we installed + void DeleteEvtHandler(); + wxWindow *m_win, *m_targetWindow; @@ -164,6 +172,8 @@ protected: #if wxUSE_MOUSEWHEEL int m_wheelRotation; #endif // wxUSE_MOUSEWHEEL + + wxScrollHelperEvtHandler *m_handler; }; // ---------------------------------------------------------------------------- diff --git a/src/generic/scrlwing.cpp b/src/generic/scrlwing.cpp index ce07d296b2..c4fbb95674 100644 --- a/src/generic/scrlwing.cpp +++ b/src/generic/scrlwing.cpp @@ -64,7 +64,7 @@ IMPLEMENT_CLASS(wxScrolledWindow, wxGenericScrolledWindow) // them to wxScrollHelper // ---------------------------------------------------------------------------- -class wxScrollHelperEvtHandler : public wxEvtHandler +class WXDLLEXPORT wxScrollHelperEvtHandler : public wxEvtHandler { public: wxScrollHelperEvtHandler(wxScrollHelper *scrollHelper) @@ -74,8 +74,12 @@ public: virtual bool ProcessEvent(wxEvent& event); + void ResetDrawnFlag() { m_hasDrawnWindow = FALSE; } + private: wxScrollHelper *m_scrollHelper; + + bool m_hasDrawnWindow; }; // ---------------------------------------------------------------------------- @@ -169,13 +173,41 @@ bool wxScrollHelperEvtHandler::ProcessEvent(wxEvent& event) { wxEventType evType = event.GetEventType(); + // always process the size events ourselves, even if the user code handles + // them as well, as we need to AdjustScrollbars() if ( evType == wxEVT_SIZE ) { m_scrollHelper->HandleOnSize((wxSizeEvent &)event); } + // the explanation of wxEVT_PAINT processing hack: for historic reasons + // there are 2 ways to process this event in classes deriving from + // wxScrolledWindow. The user code may + // + // 1. override wxScrolledWindow::OnDraw(dc) + // 2. define its own OnPaint() handler + // + // In addition, in wxUniversal wxWindow defines OnPaint() itself and + // always processes the draw event, so we can't just try the window + // OnPaint() first and call our HandleOnPaint() if it doesn't process it + // (the latter would never be called in wxUniversal). + // + // So the solution is to have a flag telling us whether the user code drew + // anything in the window. We set it to true here but reset it to false in + // wxScrolledWindow::OnPaint() handler (which wouldn't be called if the + // user code defined OnPaint() in the derived class) + m_hasDrawnWindow = TRUE; + if ( wxEvtHandler::ProcessEvent(event) ) - return TRUE; + { + // normally, nothing more to do here - except if it was a paint event + // which wasn't really processed, then we'll try to call our + // OnDraw() below (from HandleOnPaint) + if ( !m_hasDrawnWindow ) + { + return TRUE; + } + } // reset the skipped flag to FALSE as it might have been set to TRUE in // ProcessEvent() above @@ -252,29 +284,17 @@ wxScrollHelper::wxScrollHelper(wxWindow *win) m_timerAutoScroll = (wxTimer *)NULL; + m_handler = NULL; + if ( win ) SetWindow(win); } -void wxScrollHelper::SetWindow(wxWindow *win) -{ - wxCHECK_RET( win, _T("wxScrollHelper needs a window to scroll") ); - - m_targetWindow = m_win = win; - - // install the event handler which will intercept the events we're - // interested in - m_win->PushEventHandler(new wxScrollHelperEvtHandler(this)); -} - wxScrollHelper::~wxScrollHelper() { StopAutoScrolling(); - if ( m_targetWindow ) - m_targetWindow->PopEventHandler(TRUE /* do delete it */); - if ( m_win && m_win != m_targetWindow) - m_win->PopEventHandler(TRUE /* do delete it */); + DeleteEvtHandler(); } // ---------------------------------------------------------------------------- @@ -357,20 +377,44 @@ void wxScrollHelper::SetScrollbars(int pixelsPerUnitX, // target window handling // ---------------------------------------------------------------------------- +void wxScrollHelper::DeleteEvtHandler() +{ + // FIXME: we should search for m_handler in the handler list + if ( m_targetWindow ) + { + m_targetWindow->PopEventHandler(TRUE /* Delete old event handler*/); + } +} + +void wxScrollHelper::SetWindow(wxWindow *win) +{ + wxCHECK_RET( win, _T("wxScrollHelper needs a window to scroll") ); + + m_win = win; + + DoSetTargetWindow(win); +} + +void wxScrollHelper::DoSetTargetWindow(wxWindow *target) +{ + m_targetWindow = target; + + // install the event handler which will intercept the events we're + // interested in + m_handler = new wxScrollHelperEvtHandler(this); + m_targetWindow->PushEventHandler(m_handler); +} + void wxScrollHelper::SetTargetWindow( wxWindow *target ) { - wxASSERT_MSG( target, wxT("target window must not be NULL") ); - // FIXME: There is a potential problem with this way of deleting - // event handlers, basically you can not be sure that you delete - // the event handler that was create by this wxScrollHelper. - // Remove the old event handler from the previous target scroll window. - if (m_targetWindow && m_targetWindow != m_win) - m_targetWindow->PopEventHandler(TRUE /* Delete old event handler*/); - m_targetWindow = target; - // Install a new event handler, which will intercept the events we're - // interested in from the target scroll window. - if (m_targetWindow != m_win) - m_targetWindow->PushEventHandler(new wxScrollHelperEvtHandler(this)); + wxCHECK_RET( target, wxT("target window must not be NULL") ); + + if ( target == m_targetWindow ) + return; + + DeleteEvtHandler(); + + DoSetTargetWindow(target); } wxWindow *wxScrollHelper::GetTargetWindow() const @@ -1019,6 +1063,10 @@ void wxScrollHelper::HandleOnMouseWheel(wxMouseEvent& event) IMPLEMENT_DYNAMIC_CLASS(wxGenericScrolledWindow, wxPanel) +BEGIN_EVENT_TABLE(wxGenericScrolledWindow, wxPanel) + EVT_PAINT(wxGenericScrolledWindow::OnPaint) +END_EVENT_TABLE() + bool wxGenericScrolledWindow::Create(wxWindow *parent, wxWindowID id, const wxPoint& pos, @@ -1042,7 +1090,17 @@ wxGenericScrolledWindow::~wxGenericScrolledWindow() { } +void wxGenericScrolledWindow::OnPaint(wxPaintEvent& event) +{ + // the user code didn't really draw the window if we got here, so set this + // flag to try to call OnDraw() later + m_handler->ResetDrawnFlag(); + + event.Skip(); +} + #if WXWIN_COMPATIBILITY + void wxGenericScrolledWindow::GetScrollUnitsPerPage (int *x_page, int *y_page) const { *x_page = GetScrollPageSize(wxHORIZONTAL); @@ -1056,6 +1114,7 @@ void wxGenericScrolledWindow::CalcUnscrolledPosition(int x, int y, float *xx, fl if ( yy ) *yy = (float)(y + m_yScrollPosition * m_yScrollPixelsPerLine); } + #endif // WXWIN_COMPATIBILITY #endif // !wxGTK