在这张图片中...
...您可以看到每个“线条颜色”标签旁边都有一个彩色圆圈。
在我的项目中，彩色圆圈是一个 Swatch。这是 Swatch 的完整代码文件：
public class Swatch : System.Windows.Forms.Panel
{
/*private int _Radius = 20;
[System.ComponentModel.Category("Layout")]
public int Radius
{
get { return _Radius; }
set { _Radius = value; }
} */
private System.Drawing.Color _BorderColor = System.Drawing.Color.Transparent;
[System.ComponentModel.Category("Appearance")]
public System.Drawing.Color BorderColor
{
get { return _BorderColor; }
set { _BorderColor = value; }
}
private System.Drawing.Color _FillColor = System.Drawing.Color.Blue;
[System.ComponentModel.Category("Appearance")]
public System.Drawing.Color FillColor
{
get { return _FillColor; }
set { _FillColor = value; }
}
protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
{
base.OnPaint(e);
System.Drawing.Rectangle RealRect = new System.Drawing.Rectangle(e.ClipRectangle.Location, e.ClipRectangle.Size);
RealRect.Inflate(-1, -1);
int Radius = Math.Min(RealRect.Size.Height, RealRect.Size.Width);
System.Drawing.Rectangle SqRect = new System.Drawing.Rectangle();
SqRect.Location = RealRect.Location;
SqRect.Size = new System.Drawing.Size(Radius, Radius);
System.Drawing.Drawing2D.CompositingQuality PrevQual = e.Graphics.CompositingQuality;
using (System.Drawing.SolidBrush Back = new System.Drawing.SolidBrush(this.FillColor))
{
using (System.Drawing.Pen Pen = new System.Drawing.Pen(new System.Drawing.SolidBrush(this.BorderColor)))
{
//e.Graphics.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
e.Graphics.FillEllipse(Back, SqRect);
e.Graphics.DrawEllipse(Pen, SqRect);
}
}
e.Graphics.CompositingQuality = PrevQual;
}
public Swatch()
{
this.SetStyle(System.Windows.Forms.ControlStyles.UserPaint, true);
this.SetStyle(System.Windows.Forms.ControlStyles.OptimizedDoubleBuffer, true);
this.SetStyle(System.Windows.Forms.ControlStyles.AllPaintingInWmPaint, true);
this.SetStyle(System.Windows.Forms.ControlStyles.ResizeRedraw, true);
this.SetStyle(System.Windows.Forms.ControlStyles.SupportsTransparentBackColor, true);
this.DoubleBuffered = true;
}
}
每行都是一个 UserControl，它由一个 TableLayoutPanel、标签、一个 Swatch 控件和一个 NumericUpDown 框组成。
大约有 10 行，它们被放置在 TableLayoutPanel 中，它位于选项卡控件上的 TabPage 内。标签页已AutoScroll设置为true溢出导致标签页滚动。
问题是每当我运行应用程序并上下滚动时，色板（彩色圆圈）会撕裂并显示各种伪影，如上图所示。我想要干净的滚动，没有渲染工件。
我尝试过使用SetStyle（如这里建议的以 Windows 形式绘制问题），但它没有任何效果。
UserControl（每行）已DoubleBuffered设置为true，这也没有任何效果。
我担心我错过了一些相当明显的东西。