Using the brush / paint code / animate?

[myblueocean]

Hi there,

I would like to know if you can animate the brush / paint code, so for example lets say you have a square and as soon as you run that program. The square moves to the left, with no interaction from you?

 

[zekeman]

Maybe there is a better way but you could use a timer.

 

[myblueocean]

"'Draw a 200 pixel blue rectangle 20 pixels from the top of the form.
e.Graphics.DrawRectangle(Pens.blue, 10, 20, 20, 20)
'fill the square with a different colour.
e.Graphics.FillRectangle(Brushes.blue, 10, 20, 20, 20)"

This is the code, so how would I go about get this to move using a timer?

 

[waynespangler]

Try something like this:

	Dim bmp As Bitmap = Nothing
	Dim RectSize As Rectangle = New Rectangle(0, 0, 100, 100)

	Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
		Me.Show()
		bmp = New Bitmap(Me.ClientRectangle.Width, Me.ClientRectangle.Height, Imaging.PixelFormat.Format32bppArgb)
		Using g As Graphics = Graphics.FromImage(bmp)
			Dim col As Color = Me.BackColor
			g.Clear(col)
		End Using
		For x As Integer = Me.ClientRectangle.Width + 10 To -110 Step -1
			DrawRectangle(New Point(x, (Me.ClientRectangle.Height - 100) / 2))
		Next
	End Sub

	Private Sub DrawRectangle(ByVal Loc As Point)
		RectSize.X = Loc.X
		RectSize.Y = Loc.Y
		Dim g As Graphics = Me.CreateGraphics()
		g.DrawImage(bmp, 0, 0)
		Dim pen As Pen = New Pen(Color.Red)
		g.DrawRectangle(pen, RectSize)
		g.Dispose()
		pen.Dispose()
		My.Application.DoEvents()
		Threading.Thread.Sleep(30)
	End Sub

 

[JohnH]

Don't use CreateGraphics for drawing, use the Paint event. Force a Refresh/Invalidate if needed. You also shouldn't Sleep the UI thread.

 

[myblueocean]

I'm now kind of lost here...Um, I'm back to square one, so how do you get that small square to move in any direction you want once it has been debugged?

 

[JohnH]

By providing the rectangle coordinate where you want it to draw and then calling for Refresh in order for Paint event to do its job repainting it at the new place.

 

[myblueocean]

"JohnH" Could you give me some example code? So I can type it in myself.

 

[JohnH]

Private drawRect As New Rectangle(0, 0, 50, 50)

Private Sub frmDiv_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
    e.Graphics.DrawRectangle(Pens.DarkGreen, drawRect)
End Sub

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
    drawRect.Offset(1, 1)
    Me.Refresh()
End Sub