Turning PaintEventArgs into a BackroundWorker

For the program listed below (a basic scrolling graph i found, and am altering), im trying to contain the PaintEventArgs to a backgroundworker such that it doesnt lock up my program, but im having trouble figuring out how to do this as im still somewhat new to this level of VB, if anyone could give me any tips or anything that would be greatly appreciated.

Current Code:

Code:

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Imports System.ComponentModel

Public Class Form1

    Dim WithEvents VGraph As New BackgroundWorker

    Private rndGen As New Random

    Private _DataPoints As List(Of Integer)
    Public Property DataPoints() As List(Of Integer)
        Get
            If _DataPoints Is Nothing Then
                _DataPoints = New List(Of Integer)
            End If

            Return _DataPoints
        End Get
        Set(ByVal value As List(Of Integer))
            _DataPoints = CType(value, List(Of Integer))
        End Set
    End Property

    Private _DrawOn As Image
    Public ReadOnly Property DrawOn() As Image
        Get
            Return _DrawOn
        End Get
    End Property

    Private Sub panDisplay_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs)
        Dim PanelToPaint As Panel = CType(sender, Panel)
        Dim DrawAt As Point
        Dim DrawMid As New Point(0, 140)

        Dim DrawPoints As New List(Of Point)

        'draw the image on the panel if it exist
        If DrawOn IsNot Nothing Then
            e.Graphics.DrawImage(DrawOn, New Point(5, 10))
        End If

        'Create a new bitmap
        _DrawOn = New Bitmap(PanelToPaint.Width, PanelToPaint.Height)

        'Create a Graphics object from the bitmap
        Dim imgGraphics As Graphics = Graphics.FromImage(DrawOn)

        'set start point
        DrawPoints.Add(DrawMid)

        'add points until off panel
        For Each DatPoint As Integer In DataPoints
            DrawAt = New Point(DrawMid.X + 5, 30)
            DrawMid = New Point(DrawAt.X + 5, 100)

            With DrawPoints
                .Add(DrawAt)
                .Add(DrawMid)
            End With

            If DrawAt.X > PanelToPaint.Width Then
                Exit For
            End If
        Next

        'set image backcolor to same as panel
        imgGraphics.Clear(PanelToPaint.BackColor)

        'draw lines if there are any to draw
        If DrawPoints.Count > 2 Then
            imgGraphics.DrawLines(Pens.LimeGreen, DrawPoints.ToArray)
        End If

        'save the lines to the image
        imgGraphics.Save()

        'add random test data
        DataPoints.Insert(0, rndGen.Next(0, 280))
        Threading.Thread.Sleep(1000)

        're-fire the paint event
        'thus creating the endless loop
        PanelToPaint.Invalidate()
    End Sub

    Public Sub VGraph_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs) Handles VGraph.DoWork



    End Sub

    'below code creates the controls for the example at runtime so you don't have to.
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        With Me

            .DoubleBuffered = True

        End With

        AddHandler newPanel.Paint, AddressOf panDisplay_Paint

    End Sub

End Class

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Paint events can't be handled like this. It's very unlikely that any paint events are the cause of any major delays though. I think you need to look for your problems somewhere else.

Well if i have visual basic dynamically adding data to an excel file, is there a way to create a dynamically updating graph imported to visual basic from excel?

If your data is coming from the VB program, why do you need to import it back from Excel rather than using it directly? If anything is going to slow things down, that is!

Yes my data is being produced by a backgroundworker in visual basic, and I would LOVE to do that however i need visual basic to display a dynamically scrolling graph, and im not sure how to do that in visual basic (im using VB 2010).

Or is there a way to set up a chart and set it so that only a certain number of x-axis values appear on the chart, and the min and max x values are constantly increasing by 1 making it look like the graph is scrolling? Ive got a basic program listed below, if anyone could do what im asking with it, itd be greatly appreciated:

Code:

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Public Class Form1

    Dim rndm As New Random

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

        Timer1.Interval = 1000


        Chart1.Series(0).Points.AddXY(Now, 100)


        Chart1.Series(0).XValueType = DataVisualization.Charting.ChartValueType.Time
        Chart1.Series(0).ChartType = DataVisualization.Charting.SeriesChartType.Line

        Chart1.ChartAreas(0).AxisY.Minimum = 100
        Chart1.ChartAreas(0).AxisY.Maximum = 130
        Chart1.ChartAreas(0).AxisY.Interval = 10

        Chart1.ChartAreas(0).AxisX.LabelStyle.Format = "mm:ss"

        Timer1.Start()

    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Chart1.Series(0).Points.AddXY(Now, rndm.Next(100, 131))
    End Sub

End Class

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I'm not sure how you could put PaintEventArgs in a backgroundworker because a backgroundworker cannot access the UI thread.

Quote:

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Originally Posted by circuits2

I'm not sure how you could put PaintEventArgs in a backgroundworker because a backgroundworker cannot access the UI thread.

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What im trying to achieve is a dynamically scrolling graph, but i cant figure out how to do it for the life of me.

Since you are doing the data manipulation in a backgroundworker, why not use the progresschanged event to "scroll" your chart?

Quote:

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Originally Posted by circuits2

Since you are doing the data manipulation in a backgroundworker, why not use the progresschanged event to "scroll" your chart?

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Im unfamiliar with the progresschanged event also i dont even know how one would scroll a chart.

Actually i just though of how to scroll a chart, i have to shift the variables one data point to the right every time i get a new piece of data, however i dont know how to limit the max number of X-Axis items, or how to remove the X-Axis labels for each line.

The axis labels are a collection like everything else. You can set the x-axis labels each time you increment the data.

This gives you an idea of accessing the labels. I haven't dealt with charts enough to be more insightful on the code portion:

http://www.gigasoft.com/netcharting.html