' RandomCircles Example

' Draw random circles in the Paint event handler of 
' a picture box.  The circles are not redrawn until
' the Draw Circles menu item is clicked.

Public Class Form1


    Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

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

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.  
    'Do not modify it using the code editor.
    Friend WithEvents picDisplay As System.Windows.Forms.PictureBox
    Friend WithEvents MainMenu1 As System.Windows.Forms.MainMenu
    Friend WithEvents mnuBrushes As System.Windows.Forms.MenuItem
    Friend WithEvents mnuMaxRad As System.Windows.Forms.MenuItem
    Friend WithEvents mnuMaxRad50 As System.Windows.Forms.MenuItem
    Friend WithEvents mnuMaxRad100 As System.Windows.Forms.MenuItem
    Friend WithEvents mnuMaxRad200 As System.Windows.Forms.MenuItem
    Friend WithEvents mnuPlot As System.Windows.Forms.MenuItem
    Friend WithEvents mnuNumCircles200 As System.Windows.Forms.MenuItem
    Friend WithEvents mnuNumCircles500 As System.Windows.Forms.MenuItem
    Friend WithEvents mnuNumCircles1000 As System.Windows.Forms.MenuItem
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.picDisplay = New System.Windows.Forms.PictureBox
        Me.MainMenu1 = New System.Windows.Forms.MainMenu
        Me.mnuBrushes = New System.Windows.Forms.MenuItem
        Me.mnuNumCircles200 = New System.Windows.Forms.MenuItem
        Me.mnuNumCircles500 = New System.Windows.Forms.MenuItem
        Me.mnuNumCircles1000 = New System.Windows.Forms.MenuItem
        Me.mnuMaxRad = New System.Windows.Forms.MenuItem
        Me.mnuMaxRad50 = New System.Windows.Forms.MenuItem
        Me.mnuMaxRad100 = New System.Windows.Forms.MenuItem
        Me.mnuMaxRad200 = New System.Windows.Forms.MenuItem
        Me.mnuPlot = New System.Windows.Forms.MenuItem
        Me.SuspendLayout()
        '
        'picDisplay
        '
        Me.picDisplay.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle
        Me.picDisplay.Location = New System.Drawing.Point(192, 88)
        Me.picDisplay.Name = "picDisplay"
        Me.picDisplay.Size = New System.Drawing.Size(80, 64)
        Me.picDisplay.TabIndex = 0
        Me.picDisplay.TabStop = False
        '
        'MainMenu1
        '
        Me.MainMenu1.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnuBrushes, Me.mnuMaxRad, Me.mnuPlot})
        '
        'mnuBrushes
        '
        Me.mnuBrushes.Index = 0
        Me.mnuBrushes.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnuNumCircles200, Me.mnuNumCircles500, Me.mnuNumCircles1000})
        Me.mnuBrushes.Text = "Number of Circles"
        '
        'mnuNumCircles200
        '
        Me.mnuNumCircles200.Index = 0
        Me.mnuNumCircles200.Text = "200"
        '
        'mnuNumCircles500
        '
        Me.mnuNumCircles500.Index = 1
        Me.mnuNumCircles500.Text = "500"
        '
        'mnuNumCircles1000
        '
        Me.mnuNumCircles1000.Index = 2
        Me.mnuNumCircles1000.Text = "1000"
        '
        'mnuMaxRad
        '
        Me.mnuMaxRad.Index = 1
        Me.mnuMaxRad.MenuItems.AddRange(New System.Windows.Forms.MenuItem() {Me.mnuMaxRad50, Me.mnuMaxRad100, Me.mnuMaxRad200})
        Me.mnuMaxRad.Text = "Max Radius"
        '
        'mnuMaxRad50
        '
        Me.mnuMaxRad50.Index = 0
        Me.mnuMaxRad50.Text = "50"
        '
        'mnuMaxRad100
        '
        Me.mnuMaxRad100.Index = 1
        Me.mnuMaxRad100.Text = "100"
        '
        'mnuMaxRad200
        '
        Me.mnuMaxRad200.Index = 2
        Me.mnuMaxRad200.Text = "200"
        '
        'mnuPlot
        '
        Me.mnuPlot.Index = 2
        Me.mnuPlot.Text = "Plot Circles"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(328, 266)
        Me.Controls.Add(Me.picDisplay)
        Me.Menu = Me.MainMenu1
        Me.Name = "Form1"
        Me.Text = "RandomPoints Example"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Dim nCircles As Integer = 200
    Dim maxRadius As Integer = 50

    Private Sub ResizePictureBox()

        picDisplay.Location = New Point(0, 0)
        picDisplay.Size = Me.ClientSize
    End Sub
    Private Sub ResizePictureBox(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load, MyBase.Resize

        ResizePictureBox()
    End Sub

    Private Sub Form1_Resize(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles MyBase.Resize

        ResizePictureBox()
    End Sub

    Private Sub picDisplay_Paint(ByVal sender As Object, _
        ByVal e As System.Windows.Forms.PaintEventArgs) Handles picDisplay.Paint

        Dim g As Graphics = e.Graphics
        Dim r As New Random
        Dim c, i, x, y, rad, red, green, blue As Integer
        Dim w As Integer = picDisplay.Width
        Dim h As Integer = picDisplay.Height
        Dim blackPen As New Pen(Color.Black)

        For i = 1 To nCircles
            x = r.Next(0, w)
            y = r.Next(0, h)
            rad = r.Next(2, maxRadius)
            red = r.Next(0, 256)
            green = r.Next(0, 256)
            blue = r.Next(0, 256)
            Dim b As New SolidBrush(Color.FromArgb(red, green, blue))
            g.FillEllipse(b, x, y, rad, rad)
            g.DrawEllipse(blackPen, x, y, rad, rad)
            b.Dispose()
        Next
        blackPen.Dispose()
    End Sub

    Private Sub mnuNumCircles50_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuNumCircles200.Click

        nCircles = 200
    End Sub

    Private Sub mnuNumCircles100_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuNumCircles500.Click

        nCircles = 500
    End Sub

    Private Sub mnuNumCircles200_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuNumCircles1000.Click

        nCircles = 1000
    End Sub

    Private Sub mnuMaxRad50_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuMaxRad50.Click

        maxRadius = 50
    End Sub

    Private Sub mnuMaxRad100_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuMaxRad100.Click

        maxRadius = 100
    End Sub

    Private Sub mnuMaxRad200_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuMaxRad200.Click

        maxRadius = 200
    End Sub

    Private Sub mnuPlot_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles mnuPlot.Click

        picDisplay.Invalidate()
    End Sub
End Class