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[wxWidgets.git] / include / wx / vscroll.h

diff --git a/include/wx/vscroll.h b/include/wx/vscroll.h
index 73d3815d13f00eddc4bafce9f2c45f6d2f607bf0..5f4f2cb0a625b9945aa060b7c24487b0090a5ab4 100644 (file)
--- a/include/wx/vscroll.h
+++ b/include/wx/vscroll.h
@@ -62,7 +62,7 @@ public:
     // just as with the ctor above, wxVSCROLL style is always used, there is no
     // need to specify it
     bool Create(wxWindow *parent,
-                wxWindowID id,
+                wxWindowID id = wxID_ANY,
                 const wxPoint& pos = wxDefaultPosition,
                 const wxSize& size = wxDefaultSize,
                 long style = 0,
@@ -93,7 +93,11 @@ public:
     // redraw the specified line
     void RefreshLine(size_t line);
 
-    // return the item at the specified (in physical coordinates) position or
+    // redraw all lines in the specified range (inclusive)
+    void RefreshLines(size_t from, size_t to);
+
+    // return the item at the specified (in physical coordinates) position or.
+
     // wxNOT_FOUND if none, i.e. if it is below the last item
     int HitTest(wxCoord x, wxCoord y) const;
     int HitTest(const wxPoint& pt) const { return HitTest(pt.x, pt.y); }
@@ -140,14 +144,24 @@ protected:
     // usual
     virtual void OnGetLinesHint(size_t lineMin, size_t lineMax) const { }
 
+    // when the number of lines changes, we try to estimate the total height
+    // of all lines which is a rather expensive operation in terms of lines
+    // access, so if the user code may estimate the average height
+    // better/faster than we do, it should override this function to implement
+    // its own logic
+    //
+    // this function should return the best guess for the total height it may
+    // make
+    virtual wxCoord EstimateTotalHeight() const;
+
 
     // the event handlers
     void OnSize(wxSizeEvent& event);
     void OnScroll(wxScrollWinEvent& event);
 
     // find the index of the line we need to show at the top of the window such
-    // that the last line shown is the given one
-    size_t FindFirstFromBottom(size_t lineLast);
+    // that the last (fully or partially) visible line is the given one
+    size_t FindFirstFromBottom(size_t lineLast, bool fullyVisible = false);
 
     // get the total height of the lines between lineMin (inclusive) and
     // lineMax (exclusive)