// them to wxScrollHelper
// ----------------------------------------------------------------------------
-class wxScrollHelperEvtHandler : public wxEvtHandler
+class WXDLLEXPORT wxScrollHelperEvtHandler : public wxEvtHandler
{
public:
wxScrollHelperEvtHandler(wxScrollHelper *scrollHelper)
virtual bool ProcessEvent(wxEvent& event);
+ void ResetDrawnFlag() { m_hasDrawnWindow = FALSE; }
+
private:
wxScrollHelper *m_scrollHelper;
+
+ bool m_hasDrawnWindow;
};
// ----------------------------------------------------------------------------
{
wxEventType evType = event.GetEventType();
+ // 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;
+
+ // pass it on to the real handler
+ bool processed = wxEvtHandler::ProcessEvent(event);
+
+ // always process the size events ourselves, even if the user code handles
+ // them as well, as we need to AdjustScrollbars()
+ //
+ // NB: it is important to do it after processing the event in the normal
+ // way as HandleOnSize() may generate a wxEVT_SIZE itself if the
+ // scrollbar[s] (dis)appear and it should be seen by the user code
+ // after this one
if ( evType == wxEVT_SIZE )
{
m_scrollHelper->HandleOnSize((wxSizeEvent &)event);
- }
- if ( wxEvtHandler::ProcessEvent(event) )
return TRUE;
+ }
+
+ if ( processed )
+ {
+ // 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
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();
}
// ----------------------------------------------------------------------------
// target window handling
// ----------------------------------------------------------------------------
-void wxScrollHelper::SetTargetWindow( wxWindow *target )
+void wxScrollHelper::DeleteEvtHandler()
{
- 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)
+ // 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 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));
+
+ // 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 )
+{
+ wxCHECK_RET( target, wxT("target window must not be NULL") );
+
+ if ( target == m_targetWindow )
+ return;
+
+ DeleteEvtHandler();
+
+ DoSetTargetWindow(target);
}
wxWindow *wxScrollHelper::GetTargetWindow() const
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,
{
}
+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);
if ( yy )
*yy = (float)(y + m_yScrollPosition * m_yScrollPixelsPerLine);
}
+
#endif // WXWIN_COMPATIBILITY
#endif // !wxGTK
projects / wxWidgets.git / blobdiff