Paint方法閃爍

Question

考慮以下塗料函數（縮寫）：

public void paint(object sender, PaintEventArgs e) 
{ 
    base.OnPaint(e); 

    Graphics g = e.Graphics; 

    BufferedGraphicsContext context = BufferedGraphicsManager.Current; 
    BufferedGraphics buffer = context.Allocate(g, e.ClipRectangle); 

    buffer.Graphics.Clear(Color.PaleVioletRed); 

    // skip drawing if cond is true (condition is not relevant) 
    if(!cond) 
    { 
     try 
     { 
      // l is some List<p> 
      foreach(Point p in l) 
      { 
      // ...calculate X and Y... (not relevant) 

      buffer.Graphics.FillEllipse(new SolidBrush(Color.Blue), p.X,p.Y, Point.SIZE,Point.SIZE); 
      }           
     } 

     catch {} // some exception handling (not relevant) 

     finally{ 
      buffer.Render(g); 
     } 
    }     
    buffer.Render(g); 
} 

注意，上面的碼是多還是僞代碼以下。我希望使用BufferedGraphics對象時，閃爍會消失。事實上，它沒有。起初，我認爲繪畫方法會花費很長時間，大概不會（每次調用我都會測量4-7毫秒）。如果我將cond設置爲true，它仍然會閃爍，儘管繪畫方法幾乎沒有時間。可能很重要的是繪畫方法會繪製在面板上，並且我使用計時器大致每隔50毫秒使面板失效。我怎樣才能最終消除閃爍？

Answer 1

剛剛嘗試在構造函數中設置屬性：

this.DoubleBuffered = true; 

那麼你不應該需要BufferedGraphics東西：

public void paint(object sender, PaintEventArgs e) 
{ 
    base.OnPaint(e); 

    Graphics g = e.Graphics;  
    g.Clear(Color.PaleVioletRed); 

    // skip drawing if cond is true (condition is not relevant) 
    if(!cond) 
    { 
    // l is some List<p> 
    foreach(Point p in l) 
    { 
     // ...calculate X and Y... (not relevant) 
     g.FillEllipse(new SolidBrush(Color.Blue), p.X,p.Y, Point.SIZE,Point.SIZE); 
    }           
    } 
}