(completely failed so far) attempt to make wxScrolledWindow work

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/wxUNIVERSAL@8204 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/univ/window.h

@@ -80,10 +80,12 @@ public:
                               int page,
                               int range,
                               bool refresh = TRUE );
-    virtual void SetScrollPos( int orient, int pos, bool refresh = TRUE );
+    virtual void SetScrollPos(int orient, int pos, bool refresh = TRUE);
-    virtual int GetScrollPos( int orient ) const;
+    virtual int GetScrollPos(int orient) const;
-    virtual int GetScrollThumb( int orient ) const;
+    virtual int GetScrollThumb(int orient) const;
-    virtual int GetScrollRange( int orient ) const;
+    virtual int GetScrollRange(int orient) const;
+    virtual void ScrollWindow(int dx, int dy,
+                               const wxRect* rect = (wxRect *) NULL);
 
     // miscellaneous other methods
     // ---------------------------

samples/univ/univ.cpp

@@ -110,6 +110,23 @@ private:
     DECLARE_EVENT_TABLE()
 };
 
+// Define a new canvas class: we will use it for drawing
+class MyUnivCanvas : public wxScrolledWindow
+{
+public:
+    MyUnivCanvas(wxWindow *parent,
+                 const wxPoint& pos,
+                 const wxSize& size,
+                 long style = 0)
+        : wxScrolledWindow(parent, -1, pos, size, style) { }
+
+protected:
+    void OnPaint(wxPaintEvent& event);
+
+private:
+    DECLARE_EVENT_TABLE()
+};
+
 // ----------------------------------------------------------------------------
 // event tables
 // ----------------------------------------------------------------------------
@@ -122,6 +139,10 @@ BEGIN_EVENT_TABLE(MyUnivFrame, wxFrame)
     EVT_LEFT_UP(MyUnivFrame::OnLeftUp)
 END_EVENT_TABLE()
 
+BEGIN_EVENT_TABLE(MyUnivCanvas, wxScrolledWindow)
+    EVT_PAINT(MyUnivCanvas::OnPaint)
+END_EVENT_TABLE()
+
 // ============================================================================
 // implementation
 // ============================================================================
@@ -243,7 +264,7 @@ MyUnivFrame::MyUnivFrame(const wxString& title)
     sb->SetScrollbar(0, 10, 100, 10);
     sb = new wxScrollBar(this, -1, wxPoint(200, 330), wxSize(-1, 150), wxSB_VERTICAL);
     sb->SetScrollbar(50, 50, 100, 10);
-#elif 1
+#elif 0
     wxWindow *win = new wxWindow(this, -1,
                                  wxPoint(200, 300),
                                  wxSize(300, 150),
@@ -251,11 +272,12 @@ MyUnivFrame::MyUnivFrame(const wxString& title)
     win->SetScrollbar(wxHORIZONTAL, 0, 10, 30);
     win->SetScrollbar(wxVERTICAL, 0, 5, 30);
 #else
-    wxScrolledWindow *win = new wxScrolledWindow(this, -1,
+    wxScrolledWindow *win = new MyUnivCanvas(this,
                                              wxPoint(200, 300),
                                              wxSize(300, 150),
                                              wxSUNKEN_BORDER);
-    win->SetScrollbars(10, 5, 30, 30, 15, 15);
+    win->SetScrollbars(10, 10, 100, 100, 0, 0);
+    win->ScrollWindow(100, 0);
 #endif
 
     new wxButton(this, -1, wxBITMAP(open), _T("&Open..."), wxPoint(10, 420));
@@ -293,3 +315,16 @@ void MyUnivFrame::OnLeftUp(wxMouseEvent& event)
         Close();
     }
 }
+
+// ----------------------------------------------------------------------------
+// MyUnivCanvas
+// ----------------------------------------------------------------------------
+
+void MyUnivCanvas::OnPaint(wxPaintEvent& event)
+{
+    wxPaintDC dc(this);
+    dc.SetPen(*wxRED_PEN);
+    dc.DrawLine(0, 0, 1000, 1000);
+    dc.DrawText(_T("This is a canvas"), 10, 10);
+}
+

src/univ/winuniv.cpp

@@ -312,3 +312,82 @@ int wxWindow::GetScrollRange(int orient) const
     wxScrollBar *scrollbar = GetScrollbar(orient);
     return scrollbar ? scrollbar->GetRange() : 0;
 }
+
+void wxWindow::ScrollWindow(int dx, int dy, const wxRect *rect)
+{
+    wxASSERT_MSG( !rect, _T("scrolling only part of window not implemented") );
+
+    if ( !dx && !dy )
+    {
+        // nothing to do
+        return;
+    }
+
+    // calculate the part of the window which we can just redraw in the new
+    // location
+    wxSize sizeTotal = GetClientSize();
+    wxPoint ptSource, ptDest;
+    wxSize size;
+    size.x = sizeTotal.x - dx;
+    size.y = sizeTotal.y - dy;
+    if ( size.x < 0 || size.y < 0 )
+    {
+        // just redraw everything as nothing of the displayed image will stay
+        Refresh();
+    }
+    else // move the part which doesn't change to the new location
+    {
+        // positive values mean to scroll to thr right/down
+        if ( dx > 0 )
+        {
+            ptSource.x = 0;
+            ptDest.x = dx;
+        }
+        else
+        {
+            ptSource.x = dx;
+            ptDest.x = 0;
+        }
+
+        if ( dy > 0 )
+        {
+            ptSource.y = 0;
+            ptDest.y = dy;
+        }
+        else
+        {
+            ptSource.y = dy;
+            ptDest.y = 0;
+        }
+
+        // do move
+        wxClientDC dc(this);
+        dc.Blit(ptDest, size, &dc, ptSource);
+
+        // and now repaint the uncovered area
+
+        // FIXME: we repaint the intersection of these rectangles twice - is
+        //        it bad?
+
+        wxRect rect;
+        rect.x = ptSource.x;
+        rect.y = ptSource.y;
+
+        if ( dx )
+        {
+            rect.width = abs(ptDest.x - ptSource.x);
+            rect.height = sizeTotal.y;
+
+            Refresh(TRUE /* erase bkgnd */, &rect);
+        }
+
+        if ( dy )
+        {
+            rect.width = sizeTotal.x;
+            rect.height = abs(ptDest.y - ptSource.y);
+
+            Refresh(TRUE /* erase bkgnd */, &rect);
+        }
+    }
+}
+