Slow Dynamic Buttons

S

shizon

Newcomer
Joined
Oct 24, 2002
Messages
6
We were trying to create and destroy buttons in the usual way of a "control array" but it is too slow if trying to do about 100 buttons. Is there a better performing method than the standard way of doing it in vb.net?

I thought I remember something about bit something that might work. I forget what it's called. Thanks for the help.
 
Code: 
Public Sub DoButtons(ByVal uplimit As Integer)
        Dim x As Integer
        Dim xx As Integer
        Dim y As Integer
        Dim mybutt As Button
        y = 5
        xx = 1
        For x = 1 To uplimit
            TheButs(x) = New System.Windows.Forms.Button
            TheButs(x).Size = New System.Drawing.Size(36, 36)
            TheButs(x).Font = New System.Drawing.Font("Microsoft Sans Serif", 6.75!, System.Drawing.FontStyle.Regular)
            xx += 1
            If xx > 10 Then xx -= 10
            Select Case x
                Case 11
                    y = 44
                Case 21
                    y = 83 '44 + 39
                Case 31
                    y = 122 '44 + 39 * 2
                Case 41
                    y = 161 '44 + 39 * 3
                Case 51
                    y = 200 '44 + 39 * 4
                Case 61
                    y = 239 '44 + 39 * 5
                Case 71
                    y = 278 '44 + 39 * 6
                Case 81
                    y = 317 '44 + 39 * 7
                Case 91
                    y = 356 '44 + 39 * 8
                Case 101
                    y = 356 '44 + 39 * 8
            End Select
            TheButs(x).Location = New System.Drawing.Point(y, 26 + ((xx - 1) * 38))
            TheButs(x).Text = x
            Me.Controls.Add(TheButs(x))
            AddHandler TheButs(x).Click, AddressOf ButtonsAll_Click
        Next x
    End Sub
That's the sub that creates the buttons.

Code: 
 For x = 1 To NumberofButtons
            TheButs(x).Visible = True
 Next x
Sub that shows. Sub that hides is just that only with false obviously. I've tried show() and hide()
 
What spec PC are you running this on? Just cut and pasted yuor code and it was only taking approx 90ms, although if you don't create the size and font on each itteration of the loop I managed to cut about 20ms off the time.
 
I'm running it on my laptop which is 1.6 Centrino.

I guess I should also add that this is being developed for a smart application so I'm running it in the ce.net emulator. Also, I stuck a msgbox at the end of the for next to show me the time and it hits the msgbox before it's done drawing the buttons. I don't think it's a code related issue, but more a factor of drawing the buttons. I'd say it takes about 1/2 a second, maybe a little more, to draw them.

I also tested by creating another button that hides and then shows the buttons and I get no delay whatsoever.

I also did some more research and found some other talk about .NET being slow to draw controls, especially over 50. I heard from somewhere, don't remember where, that you can use bitblt to help this somehow.
 
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