C# WinForm控件美化扩展系列之ListView

昨天的文章中介绍了怎样使ListBox隔行显示不同的颜色，今天接着介绍怎样扩展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.Images[e.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.Images[e.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 - imageRect.Right - 3,

bounds.Height);

TextRenderer.DrawText(

g,

e.Item.Text,

e.Item.Font,

textRect,

e.Item.ForeColor,

flags);

return;

}

e.DrawText(flags);

}

转载：http://www.csharpwin.net/ddwstp/net/csharp/418dr7279.shtml