protected override void OnPaint(PaintEventArgs e)
{
Graphics g = Graphics.FromImage(m_Canvas);
g.Clear(BackColor);
int bound_left = 0;
int bound_width = Width;
if (m_Scrollbar.Visible)
{
bound_left = m_Scrollbar.Width;
bound_width = Width - m_Scrollbar.Width;
}
for (int i = 0; i < m_VisibleItems.Count; ++i)
{
DrawItemArgs args = new DrawItemArgs();
args.Canvas = g;
args.Item = m_VisibleItems[i];
args.Bounds = new Rectangle(bound_left, i * m_ItemHeight, bound_width - 1, m_ItemHeight);
if (args.Item == m_SelectedItem)
{
args.IsSelected = true;
args.BackColor = Color.FromArgb(255, 0, 0, 128);
args.ForeColor = Color.FromArgb(255, 255, 255, 255);
}
else
{
args.ForeColor = ForeColor;
args.BackColor = BackColor;
}
OnDrawItem(args);
}
e.Graphics.DrawImage(m_Canvas, 0, 0);
}
//绘制项目
protected void OnDrawItem(DrawItemArgs args)
{
if (args.IsSelected)
{
LinearGradientBrush lbrush1 = new LinearGradientBrush(args.Bounds, Color.Transparent, Color.FromArgb(255, 100, 100, 255), 120.0f, true);
LinearGradientBrush lbrush2 = new LinearGradientBrush(args.Bounds, Color.FromArgb(128, 255, 255, 255), Color.FromArgb(0, 100, 100, 255), -30.0f, true);
args.Canvas.FillRectangle(lbrush1, args.Bounds);
args.Canvas.FillRectangle(lbrush2, args.Bounds);
}
else
{
LinearGradientBrush lbrush1 = new LinearGradientBrush(args.Bounds, ForeColor, Color.Transparent, 120.0f, true);
LinearGradientBrush lbrush2 = new LinearGradientBrush(args.Bounds, Color.FromArgb(128, 255, 255, 255), BackColor, -45.0f, true);
args.Canvas.FillRectangle(lbrush1, args.Bounds);
args.Canvas.FillRectangle(lbrush2, args.Bounds);
}
//输出文字
SolidBrush brush = new SolidBrush(args.ForeColor);
SolidBrush shadowBrush = new SolidBrush(m_ShadowColor);
Rectangle fontLayout = new Rectangle(args.Bounds.Left + 4, args.Bounds.Top, args.Bounds.Width - 4, args.Bounds.Height);;
Rectangle shadowRect = new Rectangle(fontLayout.Left + 1, fontLayout.Top + 1, fontLayout.Width, fontLayout.Height);
string name = args.Item.Streams.GetStreamName(args.Item.StreamIndex);
args.Canvas.DrawString(name, Font, shadowBrush, shadowRect, m_FontFormat);
args.Canvas.DrawString(name, Font, brush, fontLayout, m_FontFormat);
Pen pen = new Pen(args.ForeColor);
//绘制色彩标记块
Rectangle rect = new Rectangle(args.Bounds.Right - 20, args.Bounds.Top + (m_ItemHeight - 10) / 2, 10, 10);
if (args.Item.Streams.GetStreamEnable(args.Item.StreamIndex))
{
SolidBrush colorBrush = new SolidBrush(args.Item.Streams.GetStreamColor(args.Item.StreamIndex));
args.Canvas.FillRectangle(colorBrush, rect);
}
else
{
SolidBrush colorBrush = new SolidBrush(Color.Transparent);
args.Canvas.FillRectangle(colorBrush, rect);
}
args.Canvas.DrawRectangle(pen, rect);
args.Canvas.DrawRectangle(pen, args.Bounds);
}
