don't crash trying to dereference NULL m_selection (happens when showing a grid witho...

[wxWidgets.git] / src / generic / splitter.cpp

diff --git a/src/generic/splitter.cpp b/src/generic/splitter.cpp
index 6208dfff2f242b90f4062fd4cca08ee49231f94e..5e293514bdd3b96e236bdf6fd24bc98ff39a10f0 100644 (file)
--- a/src/generic/splitter.cpp
+++ b/src/generic/splitter.cpp
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        splitter.cpp
+// Name:        src/generic/splitter.cpp

 // Purpose:     wxSplitterWindow implementation
 // Author:      Julian Smart
 // Modified by:
 // Purpose:     wxSplitterWindow implementation
 // Author:      Julian Smart
 // Modified by:


@@ -41,7 +41,7 @@ DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED)
 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_UNSPLIT)
 
 IMPLEMENT_DYNAMIC_CLASS(wxSplitterWindow, wxWindow)
 DEFINE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_UNSPLIT)
 
 IMPLEMENT_DYNAMIC_CLASS(wxSplitterWindow, wxWindow)

-IMPLEMENT_DYNAMIC_CLASS(wxSplitterEvent, wxCommandEvent)
+IMPLEMENT_DYNAMIC_CLASS(wxSplitterEvent, wxNotifyEvent)

 
 BEGIN_EVENT_TABLE(wxSplitterWindow, wxWindow)
     EVT_PAINT(wxSplitterWindow::OnPaint)
 
 BEGIN_EVENT_TABLE(wxSplitterWindow, wxWindow)
     EVT_PAINT(wxSplitterWindow::OnPaint)


@@ -49,14 +49,9 @@ BEGIN_EVENT_TABLE(wxSplitterWindow, wxWindow)
     EVT_IDLE(wxSplitterWindow::OnIdle)
     EVT_MOUSE_EVENTS(wxSplitterWindow::OnMouseEvent)
 
     EVT_IDLE(wxSplitterWindow::OnIdle)
     EVT_MOUSE_EVENTS(wxSplitterWindow::OnMouseEvent)
 

+#ifdef __WXMSW__

     EVT_SET_CURSOR(wxSplitterWindow::OnSetCursor)
     EVT_SET_CURSOR(wxSplitterWindow::OnSetCursor)

-
-    EVT_SPLITTER_SASH_POS_CHANGED(-1, wxSplitterWindow::OnSashPosChanged)
-    // NB: we borrow OnSashPosChanged for purposes of
-    // EVT_SPLITTER_SASH_POS_CHANGING since default implementation is identical
-    EVT_SPLITTER_SASH_POS_CHANGING(-1, wxSplitterWindow::OnSashPosChanged)
-    EVT_SPLITTER_DCLICK(-1,           wxSplitterWindow::OnDoubleClick)
-    EVT_SPLITTER_UNSPLIT(-1,          wxSplitterWindow::OnUnsplitEvent)
+#endif // wxMSW

 
     WX_EVENT_TABLE_CONTROL_CONTAINER(wxSplitterWindow)
 END_EVENT_TABLE()
 
     WX_EVENT_TABLE_CONTROL_CONTAINER(wxSplitterWindow)
 END_EVENT_TABLE()


@@ -114,10 +109,10 @@ void wxSplitterWindow::Init()
     m_firstY = 0;
     m_sashSize = 7;
     m_borderSize = 2;
     m_firstY = 0;
     m_sashSize = 7;
     m_borderSize = 2;

-    m_sashPosition = 0;
+    m_sashPosition = m_requestedSashPosition = 0;

     m_minimumPaneSize = 0;
     m_minimumPaneSize = 0;

-    m_sashCursorWE = new wxCursor(wxCURSOR_SIZEWE);
-    m_sashCursorNS = new wxCursor(wxCURSOR_SIZENS);
+    m_sashCursorWE = wxCursor(wxCURSOR_SIZEWE);
+    m_sashCursorNS = wxCursor(wxCURSOR_SIZENS);

     m_sashTrackerPen = new wxPen(*wxBLACK, 2, wxSOLID);
     m_lightShadowPen = (wxPen *) NULL;
     m_mediumShadowPen = (wxPen *) NULL;
     m_sashTrackerPen = new wxPen(*wxBLACK, 2, wxSOLID);
     m_lightShadowPen = (wxPen *) NULL;
     m_mediumShadowPen = (wxPen *) NULL;


@@ -136,8 +131,6 @@ void wxSplitterWindow::Init()
 
 wxSplitterWindow::~wxSplitterWindow()
 {
 
 wxSplitterWindow::~wxSplitterWindow()
 {

-    delete m_sashCursorWE;
-    delete m_sashCursorNS;

     delete m_sashTrackerPen;
     delete m_lightShadowPen;
     delete m_darkShadowPen;
     delete m_sashTrackerPen;
     delete m_lightShadowPen;
     delete m_darkShadowPen;


@@ -147,6 +140,12 @@ wxSplitterWindow::~wxSplitterWindow()
     delete m_faceBrush;
 }
 
     delete m_faceBrush;
 }
 

+void wxSplitterWindow::SetResizeCursor()
+{
+    SetCursor(m_splitMode == wxSPLIT_VERTICAL ? m_sashCursorWE
+                                              : m_sashCursorNS);
+}
+

 void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 {
     wxPaintDC dc(this);
 void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
 {
     wxPaintDC dc(this);


@@ -172,14 +171,19 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
     // reset the cursor
 #ifdef __WXMOTIF__
     SetCursor(* wxSTANDARD_CURSOR);
     // reset the cursor
 #ifdef __WXMOTIF__
     SetCursor(* wxSTANDARD_CURSOR);

-#endif
-#ifdef __WXMSW__
+#elif defined(__WXMSW__)

     SetCursor(wxCursor());
 #endif
 
     if (GetWindowStyle() & wxSP_NOSASH)
         return;
 
     SetCursor(wxCursor());
 #endif
 
     if (GetWindowStyle() & wxSP_NOSASH)
         return;
 

+    // with wxSP_LIVE_UPDATE style the splitter windows are always resized
+    // following the mouse movement while it drags the sash, without it we only
+    // draw the sash at the new position but only resize the windows when the
+    // dragging is finished
+    bool isLive = (GetWindowStyleFlag() & wxSP_LIVE_UPDATE) != 0;
+

     if (event.LeftDown())
     {
         if ( SashHitTest(x, y) )
     if (event.LeftDown())
     {
         if ( SashHitTest(x, y) )


@@ -188,22 +192,19 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
 
             m_dragMode = wxSPLIT_DRAG_DRAGGING;
 
 
             m_dragMode = wxSPLIT_DRAG_DRAGGING;
 

-            if ((GetWindowStyleFlag() & wxSP_LIVE_UPDATE) == 0)
+            if ( !isLive )

             {
             {

+                // remember the initial sash position and draw the initial
+                // shadow sash
+                m_sashPositionCurrent = m_sashPosition;
+

                 DrawSashTracker(x, y);
             }
 
             m_oldX = x;
             m_oldY = y;
 
                 DrawSashTracker(x, y);
             }
 
             m_oldX = x;
             m_oldY = y;
 

-            if ( m_splitMode == wxSPLIT_VERTICAL )
-            {
-                SetCursor(*m_sashCursorWE);
-            }
-            else
-            {
-                SetCursor(*m_sashCursorNS);
-            }
+            SetResizeCursor();

             return;
         }
     }
             return;
         }
     }


@@ -214,57 +215,52 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
         ReleaseMouse();
 
         // Erase old tracker
         ReleaseMouse();
 
         // Erase old tracker

-        if ((GetWindowStyleFlag() & wxSP_LIVE_UPDATE) == 0)
+        if ( !isLive )

         {
             DrawSashTracker(m_oldX, m_oldY);
         }
 
         {
             DrawSashTracker(m_oldX, m_oldY);
         }
 

-        // Obtain window size. We are only interested in the dimension the sash
-        // splits up
-        int window_size = GetWindowSize();
-        int new_sash_position = m_splitMode == wxSPLIT_VERTICAL ? x : y;
+        // the position of the click doesn't exactly correspond to
+        // m_sashPosition, rather it changes it by the distance by which the
+        // mouse has moved
+        int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;

 
 

-        wxSplitterEvent eventSplitter(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED,
-                                      this);
-        eventSplitter.m_data.pos = new_sash_position;
-        if ( GetEventHandler()->ProcessEvent(eventSplitter) )
+        int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
+        int posSashNew = OnSashPositionChanging(posSashOld + diff);
+        if ( posSashNew == -1 )

         {
         {

-            new_sash_position = eventSplitter.GetSashPosition();
-            if ( new_sash_position == -1 )
-            {
-                // change not allowed
-                return;
-            }
+            // change not allowed
+            return;

         }
 
         if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
         {
             // Deal with possible unsplit scenarios
         }
 
         if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )
         {
             // Deal with possible unsplit scenarios

-            if ( new_sash_position == 0 )
+            if ( posSashNew == 0 )

             {
                 // We remove the first window from the view
                 wxWindow *removedWindow = m_windowOne;
                 m_windowOne = m_windowTwo;
                 m_windowTwo = (wxWindow *) NULL;
             {
                 // We remove the first window from the view
                 wxWindow *removedWindow = m_windowOne;
                 m_windowOne = m_windowTwo;
                 m_windowTwo = (wxWindow *) NULL;

-                SendUnsplitEvent(removedWindow);
-                m_sashPosition = 0;
+                OnUnsplit(removedWindow);
+                SetSashPositionAndNotify(0);

             }
             }

-            else if ( new_sash_position == window_size )
+            else if ( posSashNew == GetWindowSize() )

             {
                 // We remove the second window from the view
                 wxWindow *removedWindow = m_windowTwo;
                 m_windowTwo = (wxWindow *) NULL;
             {
                 // We remove the second window from the view
                 wxWindow *removedWindow = m_windowTwo;
                 m_windowTwo = (wxWindow *) NULL;

-                SendUnsplitEvent(removedWindow);
-                m_sashPosition = 0;
+                OnUnsplit(removedWindow);
+                SetSashPositionAndNotify(0);

             }
             else
             {
             }
             else
             {

-                m_sashPosition = new_sash_position;
+                SetSashPositionAndNotify(posSashNew);

             }
         }
         else
         {
             }
         }
         else
         {

-            m_sashPosition = new_sash_position;
+            SetSashPositionAndNotify(posSashNew);

         }
 
         SizeWindows();
         }
 
         SizeWindows();


@@ -274,14 +270,7 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
         // Just change the cursor if required
         if ( SashHitTest(x, y) )
         {
         // Just change the cursor if required
         if ( SashHitTest(x, y) )
         {

-                if ( m_splitMode == wxSPLIT_VERTICAL )
-                {
-                    SetCursor(*m_sashCursorWE);
-                }
-                else
-                {
-                    SetCursor(*m_sashCursorNS);
-                }
+            SetResizeCursor();

         }
 #if defined(__WXGTK__) || defined(__WXMSW__)
         else
         }
 #if defined(__WXGTK__) || defined(__WXMSW__)
         else


@@ -301,46 +290,32 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
 #ifdef __WXMSW__
         // Otherwise, the cursor sometimes reverts to the normal cursor
         // during dragging.
 #ifdef __WXMSW__
         // Otherwise, the cursor sometimes reverts to the normal cursor
         // during dragging.

-        if ( m_splitMode == wxSPLIT_VERTICAL )
-        {
-            SetCursor(*m_sashCursorWE);
-        }
-        else
-        {
-            SetCursor(*m_sashCursorNS);
-        }
-#endif
+        SetResizeCursor();
+#endif // __WXMSW__

 
 

-        // Obtain window size. We are only interested in the dimension the sash
-        // splits up
-        int new_sash_position = m_splitMode == wxSPLIT_VERTICAL ? x : y;
+        int diff = m_splitMode == wxSPLIT_VERTICAL ? x - m_oldX : y - m_oldY;

 
 

-        wxSplitterEvent eventSplitter(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING,
-                                      this);
-        eventSplitter.m_data.pos = new_sash_position;
-        if ( GetEventHandler()->ProcessEvent(eventSplitter) )
+        int posSashOld = isLive ? m_sashPosition : m_sashPositionCurrent;
+        int posSashNew = OnSashPositionChanging(posSashOld + diff);
+        if ( posSashNew == -1 )

         {
         {

-            new_sash_position = eventSplitter.GetSashPosition();
-            if ( new_sash_position == -1 )
-            {
-                // change not allowed
-                return;
-            }
+            // change not allowed
+            return;

         }
 
         }
 

-        if (new_sash_position == m_sashPosition)
+        if ( posSashNew == m_sashPosition )

             return;
 
         // Erase old tracker
             return;
 
         // Erase old tracker

-        if ((GetWindowStyleFlag() & wxSP_LIVE_UPDATE) == 0)
+        if ( !isLive )

         {
             DrawSashTracker(m_oldX, m_oldY);
         }
 
         if (m_splitMode == wxSPLIT_VERTICAL)
         {
             DrawSashTracker(m_oldX, m_oldY);
         }
 
         if (m_splitMode == wxSPLIT_VERTICAL)

-            x = new_sash_position;
+            x = posSashNew;

         else
         else

-            y = new_sash_position;
+            y = posSashNew;

 
         // Remember old positions
         m_oldX = x;
 
         // Remember old positions
         m_oldX = x;


@@ -360,24 +335,21 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
 #endif // __WXMSW__
 
         // Draw new one
 #endif // __WXMSW__
 
         // Draw new one

-        if ((GetWindowStyleFlag() & wxSP_LIVE_UPDATE) == 0)
+        if ( !isLive )

         {
         {

+            m_sashPositionCurrent = posSashNew;
+

             DrawSashTracker(m_oldX, m_oldY);
         }
         else
         {
             DrawSashTracker(m_oldX, m_oldY);
         }
         else
         {

-            m_sashPosition = new_sash_position;
+            SetSashPositionAndNotify(posSashNew);

             m_needUpdating = TRUE;
         }
     }
     else if ( event.LeftDClick() )
     {
             m_needUpdating = TRUE;
         }
     }
     else if ( event.LeftDClick() )
     {

-        wxSplitterEvent eventSplitter(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED,
-                                      this);
-        eventSplitter.m_data.pt.x = x;
-        eventSplitter.m_data.pt.y = y;
-
-        (void)GetEventHandler()->ProcessEvent(eventSplitter);
+        OnDoubleClickSash(x, y);

     }
 }
 
     }
 }
 


@@ -392,19 +364,26 @@ void wxSplitterWindow::OnSize(wxSizeEvent& event)
         parent = parent->GetParent();
     }
 
         parent = parent->GetParent();
     }
 

-    bool iconized;
+    bool iconized = FALSE;

 
 

+    // wxMotif doesn't yet have a wxTopLevelWindow implementation
+#ifdef __WXMOTIF__
+    wxFrame *winTop = wxDynamicCast(parent, wxFrame);
+#else

     wxTopLevelWindow *winTop = wxDynamicCast(parent, wxTopLevelWindow);
     wxTopLevelWindow *winTop = wxDynamicCast(parent, wxTopLevelWindow);

+#endif

     if ( winTop )
     {
         iconized = winTop->IsIconized();
     }
     if ( winTop )
     {
         iconized = winTop->IsIconized();
     }

+#ifndef __WXMOTIF__

     else
     {
         wxFAIL_MSG(wxT("should have a top level parent!"));
 
         iconized = FALSE;
     }
     else
     {
         wxFAIL_MSG(wxT("should have a top level parent!"));
 
         iconized = FALSE;
     }

+#endif

 
     if ( iconized )
     {
 
     if ( iconized )
     {


@@ -420,12 +399,12 @@ void wxSplitterWindow::OnSize(wxSizeEvent& event)
         if ( m_splitMode == wxSPLIT_VERTICAL )
         {
             if ( m_sashPosition >= (cw - 5) )
         if ( m_splitMode == wxSPLIT_VERTICAL )
         {
             if ( m_sashPosition >= (cw - 5) )

-                m_sashPosition = wxMax(10, cw - 40);
+                SetSashPositionAndNotify(wxMax(10, cw - 40));

         }
         else // m_splitMode == wxSPLIT_HORIZONTAL
         {
             if ( m_sashPosition >= (ch - 5) )
         }
         else // m_splitMode == wxSPLIT_HORIZONTAL
         {
             if ( m_sashPosition >= (ch - 5) )

-                m_sashPosition = wxMax(10, ch - 40);
+                SetSashPositionAndNotify(wxMax(10, ch - 40));

         }
     }
 
         }
     }
 


@@ -697,14 +676,6 @@ int wxSplitterWindow::AdjustSashPosition(int sashPos) const
 {
     int window_size = GetWindowSize();
 
 {
     int window_size = GetWindowSize();
 

-    if ( !window_size )
-    {
-        // don't do anything before the window has a valid size, otherwise we
-        // put the sash to 0 at the very beginning and it doesn't move from
-        // there any more
-        return sashPos;
-    }
-

     wxWindow *win;
 
     win = GetWindow1();
     wxWindow *win;
 
     win = GetWindow1();


@@ -741,18 +712,57 @@ int wxSplitterWindow::AdjustSashPosition(int sashPos) const
     return sashPos;
 }
 
     return sashPos;
 }
 

+bool wxSplitterWindow::DoSetSashPosition(int sashPos)
+{
+    int newSashPosition = AdjustSashPosition(sashPos);
+
+    if ( newSashPosition == m_sashPosition )
+        return FALSE;
+
+    m_sashPosition = newSashPosition;
+
+    return TRUE;
+}
+
+void wxSplitterWindow::SetSashPositionAndNotify(int sashPos)
+{
+    if ( DoSetSashPosition(sashPos) )
+    {
+        wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED, this);
+        event.m_data.pos = m_sashPosition;
+
+        (void)DoSendEvent(event);
+    }
+}
+

 // Position and size subwindows.
 // Note that the border size applies to each subwindow, not
 // including the edges next to the sash.
 void wxSplitterWindow::SizeWindows()
 {
 // Position and size subwindows.
 // Note that the border size applies to each subwindow, not
 // including the edges next to the sash.
 void wxSplitterWindow::SizeWindows()
 {

+    // check if we have delayed setting the real sash position
+    if ( m_requestedSashPosition != INT_MAX )
+    {
+        int newSashPosition = ConvertSashPosition(m_requestedSashPosition);
+        if ( newSashPosition != m_sashPosition )
+        {
+            DoSetSashPosition(newSashPosition);
+        }
+
+        if ( newSashPosition == m_sashPosition )
+        {
+            // don't update it any more
+            m_requestedSashPosition = INT_MAX;
+        }
+    }
+

     int w, h;
     GetClientSize(&w, &h);
 
     if ( GetWindow1() && !GetWindow2() )
     {
     int w, h;
     GetClientSize(&w, &h);
 
     if ( GetWindow1() && !GetWindow2() )
     {

-        GetWindow1()->SetSize(GetBorderSize(), GetBorderSize(), w - 2*GetBorderSize(), h - 2*GetBorderSize());
-
+        GetWindow1()->SetSize(GetBorderSize(), GetBorderSize(),
+                              w - 2*GetBorderSize(), h - 2*GetBorderSize());

     }
     else if ( GetWindow1() && GetWindow2() )
     {
     }
     else if ( GetWindow1() && GetWindow2() )
     {


@@ -790,9 +800,12 @@ void wxSplitterWindow::SizeWindows()
 // Set pane for unsplit window
 void wxSplitterWindow::Initialize(wxWindow *window)
 {
 // Set pane for unsplit window
 void wxSplitterWindow::Initialize(wxWindow *window)
 {

+    wxASSERT_MSG( window->GetParent() == this,
+                  _T("windows in the splitter should have it as parent!") );
+

     m_windowOne = window;
     m_windowTwo = (wxWindow *) NULL;
     m_windowOne = window;
     m_windowTwo = (wxWindow *) NULL;

-    m_sashPosition = 0;
+    DoSetSashPosition(0);

 }
 
 // Associates the given window with window 2, drawing the appropriate sash
 }
 
 // Associates the given window with window 2, drawing the appropriate sash


@@ -805,38 +818,40 @@ bool wxSplitterWindow::DoSplit(wxSplitMode mode,
     if ( IsSplit() )
         return FALSE;
 
     if ( IsSplit() )
         return FALSE;
 

-    int window_size = GetWindowSize();
+    wxASSERT_MSG( window1->GetParent() == this && window2->GetParent() == this,
+                  _T("windows in the splitter should have it as parent!") );

 
     m_splitMode = mode;
     m_windowOne = window1;
     m_windowTwo = window2;
 
 
     m_splitMode = mode;
     m_windowOne = window1;
     m_windowTwo = window2;
 

+    // remember the sash position we want to set for later if we can't set it
+    // right now (e.g. because the window is too small)
+    m_requestedSashPosition = sashPosition;
+
+    DoSetSashPosition(ConvertSashPosition(sashPosition));
+
+    SizeWindows();
+
+    return TRUE;
+}
+
+int wxSplitterWindow::ConvertSashPosition(int sashPosition) const
+{

     if ( sashPosition > 0 )
     {
     if ( sashPosition > 0 )
     {

-        m_sashPosition = sashPosition;
+        return sashPosition;

     }
     else if ( sashPosition < 0 )
     {
         // It's negative so adding is subtracting
     }
     else if ( sashPosition < 0 )
     {
         // It's negative so adding is subtracting

-        m_sashPosition = window_size + sashPosition;
+        return GetWindowSize() + sashPosition;

     }
     }

-    else
-    {
-        // default
-        m_sashPosition = window_size/2;
-    }
-
-    // don't do it initially, i.e. when creating the window because it doesn't
-    // have a proper size yet and AdjustSashPosition() would happily set the
-    // sash position to 0!
-    if ( window_size > 0 )
+    else // sashPosition == 0

     {
     {

-        m_sashPosition = AdjustSashPosition(m_sashPosition);
+        // default, put it in the centre
+        return GetWindowSize() / 2;

     }
     }

-
-    SizeWindows();
-
-    return TRUE;

 }
 
 // Remove the specified (or second) window from the view
 }
 
 // Remove the specified (or second) window from the view


@@ -865,8 +880,8 @@ bool wxSplitterWindow::Unsplit(wxWindow *toRemove)
         return FALSE;
     }
 
         return FALSE;
     }
 

-    SendUnsplitEvent(win);
-    m_sashPosition = 0;
+    OnUnsplit(win);
+    DoSetSashPosition(0);

     SizeWindows();
 
     return TRUE;
     SizeWindows();
 
     return TRUE;


@@ -898,9 +913,15 @@ bool wxSplitterWindow::ReplaceWindow(wxWindow *winOld, wxWindow *winNew)
     return TRUE;
 }
 
     return TRUE;
 }
 

+void wxSplitterWindow::SetMinimumPaneSize(int min)
+{
+    m_minimumPaneSize = min;
+    SetSashPosition(m_sashPosition); // re-check limits
+}
+

 void wxSplitterWindow::SetSashPosition(int position, bool redraw)
 {
 void wxSplitterWindow::SetSashPosition(int position, bool redraw)
 {

-    m_sashPosition = AdjustSashPosition(position);
+    DoSetSashPosition(position);

 
     if ( redraw )
     {
 
     if ( redraw )
     {


@@ -945,31 +966,38 @@ void wxSplitterWindow::InitColours()
 #endif // __WIN16__
 }
 
 #endif // __WIN16__
 }
 

-void wxSplitterWindow::SendUnsplitEvent(wxWindow *winRemoved)
+bool wxSplitterWindow::DoSendEvent(wxSplitterEvent& event)

 {
 {

-    wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
-    event.m_data.win = winRemoved;
-
-    (void)GetEventHandler()->ProcessEvent(event);
+    return !GetEventHandler()->ProcessEvent(event) || event.IsAllowed();

 }
 
 // ---------------------------------------------------------------------------
 }
 
 // ---------------------------------------------------------------------------

-// splitter event handlers
+// wxSplitterWindow virtual functions: they now just generate the events

 // ---------------------------------------------------------------------------
 
 // ---------------------------------------------------------------------------
 

-void wxSplitterWindow::OnSashPosChanged(wxSplitterEvent& event)
+bool wxSplitterWindow::OnSashPositionChange(int WXUNUSED(newSashPosition))
+{
+    // always allow by default
+    return TRUE;
+}
+
+int wxSplitterWindow::OnSashPositionChanging(int newSashPosition)

 {
     // If within UNSPLIT_THRESHOLD from edge, set to edge to cause closure.
     const int UNSPLIT_THRESHOLD = 4;
 
 {
     // If within UNSPLIT_THRESHOLD from edge, set to edge to cause closure.
     const int UNSPLIT_THRESHOLD = 4;
 

-    int newSashPosition = event.GetSashPosition();
+    // first of all, check if OnSashPositionChange() doesn't forbid this change
+    if ( !OnSashPositionChange(newSashPosition) )
+    {
+        // it does
+        return -1;
+    }

 
     // Obtain relevant window dimension for bottom / right threshold check
     int window_size = GetWindowSize();
 
     bool unsplit_scenario = FALSE;
 
     // Obtain relevant window dimension for bottom / right threshold check
     int window_size = GetWindowSize();
 
     bool unsplit_scenario = FALSE;

-    if ( m_permitUnsplitAlways
-            || m_minimumPaneSize == 0 )
+    if ( m_permitUnsplitAlways || m_minimumPaneSize == 0 )

     {
         // Do edge detection if unsplit premitted
         if ( newSashPosition <= UNSPLIT_THRESHOLD )
     {
         // Do edge detection if unsplit premitted
         if ( newSashPosition <= UNSPLIT_THRESHOLD )


@@ -997,50 +1025,61 @@ void wxSplitterWindow::OnSashPosChanged(wxSplitterEvent& event)
     if ( newSashPosition < 0 || newSashPosition > window_size )
         newSashPosition = window_size / 2;
 
     if ( newSashPosition < 0 || newSashPosition > window_size )
         newSashPosition = window_size / 2;
 

-    // for compatibility, call the virtual function
-    if ( !OnSashPositionChange(newSashPosition) )
+    // now let the event handler have it
+    //
+    // FIXME: shouldn't we do it before the adjustments above so as to ensure
+    //        that the sash position is always reasonable?
+    wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING, this);
+    event.m_data.pos = newSashPosition;
+
+    if ( !DoSendEvent(event) )

     {
     {

+        // the event handler vetoed the change

         newSashPosition = -1;
     }
         newSashPosition = -1;
     }

+    else
+    {
+        // it could have been changed by it
+        newSashPosition = event.GetSashPosition();
+    }

 
 

-    event.SetSashPosition(newSashPosition);
+    return newSashPosition;

 }
 
 // Called when the sash is double-clicked. The default behaviour is to remove
 // the sash if the minimum pane size is zero.
 }
 
 // Called when the sash is double-clicked. The default behaviour is to remove
 // the sash if the minimum pane size is zero.

-void wxSplitterWindow::OnDoubleClick(wxSplitterEvent& event)
+void wxSplitterWindow::OnDoubleClickSash(int x, int y)

 {
 {

-    // for compatibility, call the virtual function
-    OnDoubleClickSash(event.GetX(), event.GetY());
-
-    if ( GetMinimumPaneSize() == 0 || m_permitUnsplitAlways )
+    // new code should handle events instead of using the virtual functions
+    wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_DOUBLECLICKED, this);
+    event.m_data.pt.x = x;
+    event.m_data.pt.y = y;
+    if ( DoSendEvent(event) )

     {
     {

-        Unsplit();
+        if ( GetMinimumPaneSize() == 0 || m_permitUnsplitAlways )
+        {
+            Unsplit();
+        }

     }
     }

+    //else: blocked by user

 }
 
 }
 

-void wxSplitterWindow::OnUnsplitEvent(wxSplitterEvent& event)
+void wxSplitterWindow::OnUnsplit(wxWindow *winRemoved)

 {
 {

-    wxWindow *win = event.GetWindowBeingRemoved();
+    // do it before calling the event handler which may delete the window
+    winRemoved->Show(FALSE);

 
 

-    // do it before calling OnUnsplit() which may delete the window
-    win->Show(FALSE);
+    wxSplitterEvent event(wxEVT_COMMAND_SPLITTER_UNSPLIT, this);
+    event.m_data.win = winRemoved;

 
 

-    // for compatibility, call the virtual function
-    OnUnsplit(win);
+    (void)DoSendEvent(event);

 }
 
 }
 

-#if defined(__WXMSW__)
-    #define WXUNUSED_UNLESS_MSW(identifier)    identifier
-#else
-    #define WXUNUSED_UNLESS_MSW(identifier)    WXUNUSED(identifier)
-#endif
-
-void wxSplitterWindow::OnSetCursor(wxSetCursorEvent& WXUNUSED_UNLESS_MSW(event))
-{
-    // this is currently called (and needed) under MSW only...

 #ifdef __WXMSW__
 
 #ifdef __WXMSW__
 

+// this is currently called (and needed) under MSW only...
+void wxSplitterWindow::OnSetCursor(wxSetCursorEvent& event)
+{

     // if we don't do it, the resizing cursor might be set for child window:
     // and like this we explicitly say that our cursor should not be used for
     // children windows which overlap us
     // if we don't do it, the resizing cursor might be set for child window:
     // and like this we explicitly say that our cursor should not be used for
     // children windows which overlap us


@@ -1051,5 +1090,7 @@ void wxSplitterWindow::OnSetCursor(wxSetCursorEvent& WXUNUSED_UNLESS_MSW(event))
         event.Skip();
     }
     //else: do nothing, in particular, don't call Skip()
         event.Skip();
     }
     //else: do nothing, in particular, don't call Skip()

-#endif // wxMSW

 }
 }

+
+#endif // wxMSW
+