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,
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,
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
