How do I double buffer a Panel?

I have a panel that has a roulette wheel on it, and I need to double buffer the panel, so that it stops flickering. Can anyone help me out?

EDIT:

Yes, I have tried that.

panel1.doublebuffered does not exist, only this.doublebuffered. And I don't need to buffer the Form, just the Panel.

You need to derive from Panel or PictureBox.

There are ramifications to this depending on how you choose to enable the buffering.

If you set the this.DoubleBuffer flag then you should be ok.

If you manually update the styles then you have to paint the form yourself in WM_PAINT.

If you really feel ambitious you can maintain and draw your own back buffer as a Bitmap.


using System.Windows.Forms;

public class MyDisplay : Panel
{
    public MyDisplay()
    {
        this.DoubleBuffered = true;

        // or

        SetStyle(ControlStyles.AllPaintingInWmPaint, true);
        SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
        UpdateStyles();
    }
}

Another way of doing this is to invoke the member doublebuffered, using the InvokeMember method:

 typeof(Panel).InvokeMember("DoubleBuffered", BindingFlags.SetProperty    
            | BindingFlags.Instance | BindingFlags.NonPublic, null,
            panel2, new object[] { true });

By doing it this way, you don't have to create a subclass

You can make the DoubleBuffered-Property public in a derivided class of Panel:

public class DoubleBufferedPanel : Panel
{        
    [DefaultValue(true)]
    public new bool DoubleBuffered
    {
        get
        {
            return base.DoubleBuffered;
        }
        set
        {
            base.DoubleBuffered = value;
        }
    }
}

Winform panels have a DoubleBuffered property.

Edit: I should have noticed that it was protected. Others have described how to sub-class it. :)

Just expanding on User79775's answer, if you're trying to achieve this in VB.net, do so like this:

Imports System.Windows.Forms

Public Class MyDisplay
    Inherits Panel

    Public Sub New()
        Me.DoubleBuffered = True

        ' or

        SetStyle(ControlStyles.AllPaintingInWmPaint, True)
        SetStyle(ControlStyles.OptimizedDoubleBuffer, True)
        UpdateStyles()
    End Sub
End Class

来源：https://stackoverflow.com/questions/818415/how-do-i-double-buffer-a-panel

标签

winforms

doublebuffered