BackBuffering ! =)

Hi !

Here's the Class for BackBuffering, It's easy. =)

Code:

---

Public Class IBackBuffer
    Private mvarBitmap As System.Drawing.Bitmap
    Private mvarBuffer As System.Drawing.Graphics
    Private mvarGraphics As System.Drawing.Graphics
    Private mvarForm As System.Windows.Forms.Form

    Public Sub Connect(ByVal xForm As System.Windows.Forms.Form)
        mvarForm = xForm
        mvarGraphics = mvarForm.CreateGraphics
        mvarBitmap = New Bitmap(mvarForm.Width, mvarForm.Height)
        mvarBuffer = Graphics.FromImage(mvarBitmap)
    End Sub

    Public ReadOnly Property Graphics() As System.Drawing.Graphics
        Get
            Return mvarBuffer
        End Get
    End Property

    Public Sub DoPainting()
        mvarGraphics.DrawImage(mvarBitmap, 0, 0)
    End Sub
End Class

---

This is how you use it:

Code:

---

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim xBackBuffer As New IBackBuffer()

        'Connect BackBuffer Component to Form1
        xBackBuffer.Connect(Form1)

        '#############################
        'Do Your Graphics Drawing Here
        '#############################
        'You Draw you graphics using xBackBuffer.Graphics
        'xBackBuffer.Graphics.*
        '#############################

        'Finally, Flicker Free paint your graphics.
        xBackBuffer.DoPainting()
    End Sub

---

There you go. =)

that's cool ,yeah cool .
what does it do btw?? .lol:D

ooh that was related to the other post I guess . Thanx anyways .

i am trying to put a owner drawn item in a panel that draws a progressbar......then i do some text proccessing and i want to use it...the problem is that when i use the progress bar in it the text work gets like 30% slower and even worse the panel progressbar flickers a lot! how do i prevent it from flickering?

Are you drawing the ProgressBar (overriding the Paint event)?

If so, you should be able to do "double-buffering"...

Look up ControlStyles in your help index... and look for DoubleBuffering.

Me.SetStyles(ControlStyles.AllPaintinginWMPaint Or ControlStyles.UserPaint Or ControlStyles.DoubleBuffer, True)

Have a lookie here...

http://www.codeproject.com/vb/net/tracker.asp

yes im going read it but in the mean time i have the following method of the status bar im inheriting:

Code:

---

protected override void OnDrawItem(StatusBarDrawItemEventArgs e) {
if (e.Panel.Style == StatusBarPanelStyle.OwnerDraw) {
Graphics g = e.Graphics;
g.FillRectangle(new SolidBrush(SystemColors.ActiveCaptionText),
e.Bounds.X,
e.Bounds.Y,
GetPercentage(e.Bounds.Width),
e.Bounds.Height);
base.OnDrawItem (e);
}
}

---

sorry because its in c# but what should i change here? i tried to put ut string in the begginig and when i tried it the progress bar just shown ALL in the same color(the default one) without showing any panel :(

bah the drawning error was my fault when converting the vb.net string to c# string....now it works but it does not any double buffering(at least it still flickers a lot)

what am i suposed to do?

Ok, are you writing in C# or VB?

c# but u can say things in vb.net or c# its the same i understand them boot lol

Egh.. alright. Problems can arise because you have a form, a status bar, and a progress bar. So you basically have 3 controls that may at some point redraw themselves, and may invalidate themselves.

But from what I understand, you are invalidating just the progressbar, because you are writing text to its center, correct?

If so, the only real way I could help is to be able to look at that control class's source. And of course, if you are using .Net 2003, I probably will be out of luck.

So, try putting this in your progressbar constructor.

Code:

---

// Set the value of the double-buffering style bits to true.
  this.SetStyle(ControlStyles.DoubleBuffer |
      ControlStyles.UserPaint |
      ControlStyles.AllPaintingInWmPaint,
      true);
  this.UpdateStyles();

---

Here's a reference... http://msdn.microsoft.com/library/de...styletopic.asp

http://msdn.microsoft.com/library/de...classtopic.asp

http://msdn.microsoft.com/library/de...ncontrols7.asp

well i tried and it just doesnt paint all the status bar :(

Could you upload the source for your progressbar?

here..

hmm the project is a bit complex for me to upload but i can show the progressbar code:

Code:

---

        public class ProgressBarStatusBar : StatusBar {
                private int _progress = 0;
                public int Progress {
                        get { return _progress;
                        } set {
                                  if (value >= 0 && value <= 100) {
                                          _progress = value;
                                          Refresh();
                                  }
                          }
                }

                public ProgressBarStatusBar() {
                        SetStyle(ControlStyles.AllPaintingInWmPaint |
                                ControlStyles.UserPaint |
                                ControlStyles.DoubleBuffer, true);
                        UpdateStyles();
                }

                protected override void OnDrawItem(StatusBarDrawItemEventArgs e) {
                        if (e.Panel.Style == StatusBarPanelStyle.OwnerDraw) {
                                Graphics g = e.Graphics;
                                g.FillRectangle(new SolidBrush(SystemColors.ActiveCaptionText),
                                        e.Bounds.X,
                                        e.Bounds.Y,
                                        GetPercentage(e.Bounds.Width),
                                        e.Bounds.Height);

                                base.OnDrawItem (e);
                        }
                }

                private int GetPercentage(int panelSize) {
                        return Convert.ToInt32(
                                (double)panelSize * (double)_progress / (double)100);
                }
        }
}

---

then..just add a statusbar to ur form and add an owner drawn item.
to put a value to the progressbar do the following:
((StatusBarProgressBar)statusBar1).Progress = 50;

bump