+#include "wx/panel.h"
+
+class WXDLLIMPEXP_FWD_CORE wxScrollHelperEvtHandler;
+class WXDLLIMPEXP_FWD_CORE wxTimer;
+
+// default scrolled window style: scroll in both directions
+#define wxScrolledWindowStyle (wxHSCROLL | wxVSCROLL)
+
+// ----------------------------------------------------------------------------
+// The hierarchy of scrolling classes is a bit complicated because we want to
+// put as much functionality as possible in a mix-in class not deriving from
+// wxWindow so that other classes could derive from the same base class on all
+// platforms irrespectively of whether they are native controls (and hence
+// don't use our scrolling) or not.
+//
+// So we have
+//
+// wxScrollHelper
+// |
+// |
+// \|/
+// wxWindow wxScrollHelperNative
+// | \ / /
+// | \ / /
+// | _| |_ /
+// | wxScrolledWindow /
+// | /
+// \|/ /
+// wxControl /
+// \ /
+// \ /
+// _| |_
+// wxScrolledControl
+//
+// ----------------------------------------------------------------------------
+
+class WXDLLEXPORT wxScrollHelper
+{
+public:
+ // ctor must be given the associated window
+ wxScrollHelper(wxWindow *winToScroll);
+ virtual ~wxScrollHelper();
+
+ // configure the scrolling
+ virtual void SetScrollbars(int pixelsPerUnitX, int pixelsPerUnitY,
+ int noUnitsX, int noUnitsY,
+ int xPos = 0, int yPos = 0,
+ bool noRefresh = false );
+
+ // scroll to the given (in logical coords) position
+ virtual void Scroll(int x, int y);
+
+ // get/set the page size for this orientation (wxVERTICAL/wxHORIZONTAL)
+ int GetScrollPageSize(int orient) const;
+ void SetScrollPageSize(int orient, int pageSize);
+
+ // get the number of lines the window can scroll,
+ // returns 0 if no scrollbars are there.
+ int GetScrollLines( int orient ) const;
+
+ // Set the x, y scrolling increments.
+ void SetScrollRate( int xstep, int ystep );
+
+ // get the size of one logical unit in physical ones
+ virtual void GetScrollPixelsPerUnit(int *pixelsPerUnitX,
+ int *pixelsPerUnitY) const;
+
+ // Enable/disable Windows scrolling in either direction. If true, wxWidgets
+ // scrolls the canvas and only a bit of the canvas is invalidated; no
+ // Clear() is necessary. If false, the whole canvas is invalidated and a
+ // Clear() is necessary. Disable for when the scroll increment is used to
+ // actually scroll a non-constant distance
+ virtual void EnableScrolling(bool x_scrolling, bool y_scrolling);
+
+ // Get the view start
+ virtual void GetViewStart(int *x, int *y) const;
+
+ // Set the scale factor, used in PrepareDC
+ void SetScale(double xs, double ys) { m_scaleX = xs; m_scaleY = ys; }
+ double GetScaleX() const { return m_scaleX; }
+ double GetScaleY() const { return m_scaleY; }
+
+ // translate between scrolled and unscrolled coordinates
+ void CalcScrolledPosition(int x, int y, int *xx, int *yy) const
+ { DoCalcScrolledPosition(x, y, xx, yy); }
+ wxPoint CalcScrolledPosition(const wxPoint& pt) const
+ {
+ wxPoint p2;
+ DoCalcScrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
+ return p2;
+ }
+
+ void CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
+ { DoCalcUnscrolledPosition(x, y, xx, yy); }
+ wxPoint CalcUnscrolledPosition(const wxPoint& pt) const
+ {
+ wxPoint p2;
+ DoCalcUnscrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
+ return p2;
+ }
+
+ virtual void DoCalcScrolledPosition(int x, int y, int *xx, int *yy) const;
+ virtual void DoCalcUnscrolledPosition(int x, int y, int *xx, int *yy) const;
+
+ // Adjust the scrollbars
+ virtual void AdjustScrollbars(void);
+
+ // Calculate scroll increment
+ virtual int CalcScrollInc(wxScrollWinEvent& event);
+
+ // Normally the wxScrolledWindow will scroll itself, but in some rare
+ // occasions you might want it to scroll [part of] another window (e.g. a
+ // child of it in order to scroll only a portion the area between the
+ // scrollbars (spreadsheet: only cell area will move).
+ virtual void SetTargetWindow(wxWindow *target);
+ virtual wxWindow *GetTargetWindow() const;
+
+ void SetTargetRect(const wxRect& rect) { m_rectToScroll = rect; }
+ wxRect GetTargetRect() const { return m_rectToScroll; }
+
+ // Override this function to draw the graphic (or just process EVT_PAINT)
+ virtual void OnDraw(wxDC& WXUNUSED(dc)) { }
+
+ // change the DC origin according to the scroll position.
+ virtual void DoPrepareDC(wxDC& dc);
+
+ // are we generating the autoscroll events?
+ bool IsAutoScrolling() const { return m_timerAutoScroll != NULL; }
+
+ // stop generating the scroll events when mouse is held outside the window
+ void StopAutoScrolling();
+
+ // this method can be overridden in a derived class to forbid sending the
+ // auto scroll events - note that unlike StopAutoScrolling() it doesn't
+ // stop the timer, so it will be called repeatedly and will typically
+ // return different values depending on the current mouse position
+ //
+ // the base class version just returns true
+ virtual bool SendAutoScrollEvents(wxScrollWinEvent& event) const;
+
+ // the methods to be called from the window event handlers
+ void HandleOnScroll(wxScrollWinEvent& event);
+ void HandleOnSize(wxSizeEvent& event);
+ void HandleOnPaint(wxPaintEvent& event);
+ void HandleOnChar(wxKeyEvent& event);
+ void HandleOnMouseEnter(wxMouseEvent& event);
+ void HandleOnMouseLeave(wxMouseEvent& event);
+#if wxUSE_MOUSEWHEEL
+ void HandleOnMouseWheel(wxMouseEvent& event);
+#endif // wxUSE_MOUSEWHEEL
+
+ // FIXME: this is needed for now for wxPlot compilation, should be removed
+ // once it is fixed!
+ void OnScroll(wxScrollWinEvent& event) { HandleOnScroll(event); }