介绍怎样扩展ListView控件.doc

介绍怎样扩展ListView控件，使他也具有这样的功能，而且重绘他的Header，使其更美观。在这篇文章中，我只对View 为 Details的时候进行了重绘，至于其他的Ttile，List，SmallIcon，LargeIcon，大家可以照着代码自己实现。这个控件的美化大致跟ListBox的差不了多少，我们还是一步一步的来实现它吧：1、 继承ListView，并把 OwnerDraw 设为True,如下： public ListViewEx() : base() base.OwnerDraw = true;2、 给继承的控件添加4个属性：RowBackColor1，RowBackColor2，SelectedColor，HeadColor这三个颜色分别是数据项的交替的背景色、数据项选择后的背景色和列表头的背景颜色。3、 重绘Header，通过重写OnDrawColumnHeader函数来实现。 protected override void OnDrawColumnHeader( DrawListViewColumnHeaderEventArgs e) base.OnDrawColumnHeader(e); Graphics g = e.Graphics; Rectangle bounds = e.Bounds; Color baseColor = _headColor; Color borderColor = _headColor; Color innerBorderColor = Color.FromArgb(200, 255, 255); RenderBackgroundInternal( g, bounds, baseColor, borderColor, innerBorderColor, 0.35f, true, LinearGradientMode.Vertical); TextFormatFlags flags = GetFormatFlags(e.Header.TextAlign); Rectangle textRect = new Rectangle( bounds.X + 3, bounds.Y, bounds.Width - 6, bounds.Height); ; if (e.Header.ImageList != null) Image image = e.Header.ImageIndex = -1 ? null : e.Header.ImageList.Imagese.Header.ImageIndex; if (image != null) Rectangle imageRect = new Rectangle( bounds.X + 3, bounds.Y + 2, bounds.Height - 4, bounds.Height - 4); g.InterpolationMode = InterpolationMode.HighQualityBilinear; g.DrawImage(image, imageRect); textRect.X = imageRect.Right + 3; textRect.Width -= imageRect.Width; TextRenderer.DrawText( g, e.Header.Text, e.Font, textRect, e.ForeColor, flags); 4、 重绘 Item，通过重写OnDrawItem，OnDrawSubItem来实现，这里我只对Details这种显示模式进行了重写。 protected override void OnDrawItem(DrawListViewItemEventArgs e) base.OnDrawItem(e); if (View != View.Details) e.DrawDefault = true; protected override void OnDrawSubItem(DrawListViewSubItemEventArgs e) base.OnDrawSubItem(e); if (View != View.Details) return; if(e.ItemIndex = -1) return; Rectangle bounds = e.Bounds; ListViewItemStates itemState = e.ItemState; Graphics g = e.Graphics; if (itemState & ListViewItemStates.Selected) = ListViewItemStates.Selected) bounds.Height-; Color baseColor = _selectedColor; Color borderColor = _selectedColor; Color innerBorderColor = Color.FromArgb(200, 255, 255); RenderBackgroundInternal( g, bounds, baseColor, borderColor, innerBorderColor, 0.35f, true, LinearGradientMode.Vertical); bounds.Height+; else Color backColor = e.ItemIndex % 2 = 0 ? _rowBackColor1 : _rowBackColor2; using (SolidBrush brush = new SolidBrush(backColor) g.FillRectangle(brush, bounds); TextFormatFlags flags = GetFormatFlags(e.Header.TextAlign); if (e.ColumnIndex = 0) if (e.Item.ImageList = null) e.DrawText(flags); return; Image image = e.Item.ImageIndex = -1 ? null : e.Item.ImageList.Imagese.Item.ImageIndex; if (image = null) e.DrawText(flags); return; Rectangle imageRect = new Rectangle( bounds.X + 4, bounds.Y + 2, bounds.Height - 4, bounds.Height - 4); g.DrawImage(image, imageRect); Rectangle textRect = new Rectangle( imageRect.Right + 3, bounds.Y, bounds.Width -