Disable screen refresh

hog

hog

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I asked this before (I think) but here goes..

I have code in a forms Paint event that draws a non regular shape form and fills the backcolor property. This on its own works fine with no flicker. But say I add six controls to the form and also have code to set their backcolor property. Now I get a flicker as each control is modified and I can see each control in turn change colour.

Question is this: Is there a way to disable screen refresh so all the modifications take place then the screen is refreshed in one go?
 
For a form, type:
Code: 
SetStyle(DoubleBuffering,true)
In form load or the constructor for example.
If you want to use it in controls you have to inherit a class from the control and set the same thing in there, you have to do that, becuase this is protected in controls.
 
OK I tried this:

Code: 
 Me.SetStyle(ControlStyles.DoubleBuffer, True)

and this

Code: 
Me.SetStyle(ControlStyles.DoubleBuffer Or ControlStyles.UserPaint Or ControlStyles.AllPaintingInWmPaint, True)

Me.UpdateStyles()

both with no success:(

so I suspect your sentence re the controls may be relevant, but dumbo here appears to be in the dark regarding these things:(

any chance of another gentle nudge:)
 
What do you mean without success? :)
Is there any error or it just doesnt make anything better?

As for the control, to do what I said, make a new class, inherit it from the control you want to use, then in the constructor of the control use:
Code: 
SetStyle(DoubleBuffer,true)
SetStyle(AllPaintingInWMPAINT,true)
Then instead of using the default control from the toolbox use your own control that you inherited.
 
OK..it makes no difference:)

So I get what you mean now, but am struggling trying to achieve it:(

I havent created a control class before and have tried this but it errors....no suprises there :)

Code: 
Public Class clsPictureBox
    Inherits System.Windows.Forms.PictureBox

    Public Sub New()
        MyBase.New()

        This call is required by the Windows Form Designer.
        InitializeComponent()

        Add any initialization after the InitializeComponent() call

    End Sub

End Class

I then read a thread which said about adding a user controls or inherited user controls but am getting more lost as I go:(:(
 
That should be all good except there is no IntializeComponent sub in there, which you dont need. So remove the call to it.
:)
 
OK...still no joy, this is what I have so far:

Code: 
Public Class clsPictureBox
    Inherits System.Windows.Forms.PictureBox

    Public Sub New()
        MyBase.New()

        Add any initialization after the InitializeComponent() call

        SetStyle(ControlStyles.DoubleBuffer, True)
        SetStyle(ControlStyles.AllPaintingInWmPaint, True)

    End Sub

End Class

Then in my form I have manually entered this code?

Code: 
Friend WithEvents picGameField As clsPictureBox
Me.picGameField = New clsPictureBox

picGameField

Me.picGameField.BackColor = System.Drawing.Color.FromArgb(CType(255, Byte), CType(192, Byte), CType(255, Byte))
Me.picGameField.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
Me.picGameField.Location = New System.Drawing.Point(440, 32)
Me.picGameField.Name = "picGameField"
Me.picGameField.Size = New System.Drawing.Size(163, 304)
Me.picGameField.Visible = True

no errors occur but the picturebox does not appear either.

New ground this, creating my own controls....can u tell :)
 
Ah hold the phone...

just added this line:

Code: 
Me.Controls.Add(Me.picNextBlock)

and it appears so now to do the rest and see if it resolves the flicker:)
 
no, still get the flicker:(

No matter what I try the screen flickers. Is there no way to just tell VB, dont display the form changes until they have all been made sonething like:

Code: 
ScreenUpdating(False)

button1.backcolor=....
button2.backcolor=....
button3.backcolor=....
button4.backcolor=....
button5.backcolor=....
button6.backcolor=....

other modifications.....

ScreenUpdating(True)
 
Last edited by a moderator:
How fast are you changing the backgrounds?
PictureBoxes are not recommended for something that changes fast as they are slow.
 
Well I have a non regular shape form with 4 buttons, 2 picture boxes and three labels.

What I am tryint ot achieve is to allow the user to select the back colour of their choice, which results in the forms backcolor changing and all the controls backcolors to a off shade of the chosen colour.

What happens now is I see each control in turn change colour which results in a flicker effect on the form.
 
I tried to do something similar with 12 pictureboxes, randomly changing color in a 20millisecond timer. No flicker at all. I dont think I can help you more without seeing more of your code :).
 
Here ya go then:)

Code: 
Public Sub PaintShape()

        Dim graphPath As New Drawing2D.GraphicsPath
        Dim gfxGameGraphics As Graphics
        Dim brBrushSquare As Drawing2D.PathGradientBrush

        
        Dim arrLiner1() As Point = {New Point(323, 410), New Point(329, 368), New Point(354, 314), New Point(368, 281)}

        Dim arrLiner2() As Point = {New Point(27, 319), New Point(69, 300), New Point(87, 320), New Point(101, 292)}

        Dim arrLiner3() As Point = {New Point(773, 465), New Point(695, 320), New Point(690, 300), New Point(680, 290)}

        Dim arrLiner4() As Point = {New Point(62, 246), New Point(83, 210), New Point(110, 230), New Point(122, 185)}

        Dim arrLiner5() As Point = {New Point(867, 123), New Point(865, 123), New Point(870, 115), New Point(874, 111)}

        graphPath.AddBeziers(arrShape)

        gfxGameGraphics = Graphics.FromHwnd(Me.Handle)

        brBrushSquare = New Drawing2D.PathGradientBrush(graphPath)

        gfxGameGraphics.FillPath(New SolidBrush(clrColour), graphPath)

        gfxGameGraphics.DrawBeziers(New Pen(Color.Black, 1), arrLiner1)
        gfxGameGraphics.DrawBeziers(New Pen(Color.Black, 1), arrLiner2)
        gfxGameGraphics.DrawBeziers(New Pen(Color.Black, 1), arrLiner3)
        gfxGameGraphics.DrawBeziers(New Pen(Color.Black, 1), arrLiner4)
        gfxGameGraphics.DrawBeziers(New Pen(Color.Black, 1), arrLiner5)

        Me.Region = New Region(graphPath)

    End Sub

    Private Sub frmGame_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint

            PaintShape()

    End Sub

 Private Sub cmdColour_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdColour.Click

        Me.ColorDialog1.ShowDialog()

        clrColour = Me.ColorDialog1.Color

        clrControlColour = Color.FromArgb(150, Me.ColorDialog1.Color)

        Me.cmdStart.BackColor = clrControlColour
        Me.cmdMinimize.BackColor = clrControlColour
        Me.cmdColour.BackColor = clrControlColour
        Me.cmdClose.BackColor = clrControlColour
        Me.picGameField.BackColor = clrControlColour
        Me.picNextBlock.BackColor = clrControlColour
        Me.Label1.BackColor = clrColour
        Me.Label2.BackColor = clrColour
        Me.Label3.BackColor = clrColour

    End Sub

Ive left out the array which drawss the shape in the PaintShape procedure
 
I copied and pasted your color changing code, not a single sign of flicker. I cant try the whole thing as you took out that array.
 
Ok, what your were doing is creating all those object all the time, which is not needed, and setting region in every paint.
Look at this modified file, I hope it helps :)
 

Attachments

Thnx, Mutant, Im almost there. I had realised this may be the case and had attempted to move the offending block out of the paint procedure.

However what I hav now is the shape gets draw OK, but with no outline? And when I select a new colour the controls change with no flicker, but the main form has a bizzare odd section changed only, the rest of the form remains unchanged??
 
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