invalidate cache when RefreshLine[s]() is called

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31701 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/htmllbox.cpp

@@ -51,6 +51,15 @@ FORCE_WXHTML_MODULES()
 // the items to avoid doing it anew each time an item must be drawn
 class wxHtmlListBoxCache
 {
+private:
+    // invalidate a single item, used by Clear() and InvalidateRange()
+    void InvalidateItem(size_t n)
+    {
+        m_items[n] = (size_t)-1;
+        delete m_cells[n];
+        m_cells[n] = NULL;
+    }
+
 public:
     wxHtmlListBoxCache()
     {
@@ -76,9 +85,7 @@ public:
     {
         for ( size_t n = 0; n < SIZE; n++ )
         {
-            m_items[n] = (size_t)-1;
-            delete m_cells[n];
-            m_cells[n] = NULL;
+            InvalidateItem(n);
         }
     }
 
@@ -109,6 +116,18 @@ public:
             m_next = 0;
     }
 
+    // forget the cached value of the item(s) between the given ones (inclusive)
+    void InvalidateRange(size_t from, size_t to)
+    {
+        for ( size_t n = 0; n < SIZE; n++ )
+        {
+            if ( m_items[n] >= from && m_items[n] <= to )
+            {
+                InvalidateItem(n);
+            }
+        }
+    }
+
 private:
     // the max number of the items we cache
     enum { SIZE = 50 };
@@ -266,6 +285,20 @@ void wxHtmlListBox::OnSize(wxSizeEvent& event)
     event.Skip();
 }
 
+void wxHtmlListBox::RefreshLine(size_t line)
+{
+    m_cache->InvalidateRange(line, line);
+
+    wxVListBox::RefreshLine(line);
+}
+
+void wxHtmlListBox::RefreshLines(size_t from, size_t to)
+{
+    m_cache->InvalidateRange(from, to);
+
+    wxVListBox::RefreshLines(from, to);
+}
+
 void wxHtmlListBox::RefreshAll()
 {
     m_cache->Clear();
@@ -321,4 +354,5 @@ wxCoord wxHtmlListBox::OnMeasureItem(size_t n) const
     return cell->GetHeight() + cell->GetDescent() + 4;
 }
 
-#endif
+#endif // wxUSE_HTML
+