Bloody Scrollbars!

[wossname]

I'm trying to scroll a bitmap in a picture box using 2 scrollbars like you'd expect.

But the code only works if I set the Largechange property of the scrollbars to 0. If I use a number greater than 0 then the bitmap appears in the wrong place.

I can't see how LargeChange should make any difference.

What is the normal method for showing a bitmap in a picturebox using scrollbars?

Code would be great, please.

[pax]

Hi.

Try looking at this post...

http://www.vbforums.com/showthread.php?threadid=278843

[wossname]

That'll do nicely, thanks.

[MrPolite]

lol it's really weird how someone else asked the same question again in a short time

btw pax, I was getting some weird errors. One thing that was really really weird was that at certain times (I think when I scrolled really fast repeatedly? cant remember what I did)... scrollbar.value would have a value greater than scrollbar.maximum (whitout raising any errors) and so I had to check the Value property outside of the scrollbar class to make sure its on the right range...
also in another situation ( I dont remember again when this would happen)... when I would change the value of Maximum it wouldnt change anything. It was weird because after calling the function 3 times it would then work fine. I just took a backup of LargeChange before changing the maximum and it fixed it:

Public Shadows Property Maximum() As Integer
        Get
            ' Return the real maximum
            Return MyBase.Maximum - Me.LargeChange + 1
        End Get
        Set(ByVal Value As Integer)
            ' Calculate the 'virtual' maximum
            Dim tmp As Integer = MyBase.LargeChange
            MyBase.Maximum = Value + Me.LargeChange - 1
            MyBase.LargeChange = tmp
        End Set
    End Property

anyways wossname why are you using a scrollbar for scrolling an image? you can just use a panel, put the picturebox in it, and set the AutoScroll property of the panel to true. It would do everything for you nicely. I had to use these scrollbars because I'm drawing my image manually, dunno about you

[wossname]

Originally posted by MrPolite
anyways wossname why are you using a scrollbar for scrolling an image? you can just use a panel, put the picturebox in it, and set the AutoScroll property of the panel to true. It would do everything for you nicely. I had to use these scrollbars because I'm drawing my image manually, dunno about you

Now you bloody tell me. This .net crap is like learning programming all over again.

In my day we had VB6. I could have written this damn program in 3 hours and had done with it. I'll try the panel version.



Thanks for the tip though

[wossname]

I've tried that, but the scrollbars on the panel don't appear when the image loads.

Autosize and autoscroll on the respective controls are set true but nothing happens when a large picture is shown. I'm setting the Image property of the picturebox to a bitmap loaded using

PicMaster.Image = new Bitmap(Bitmap.FromFile(MyFileName))

What (else) am I doing wrong?

[wossname]

Never mind, I've got it working.

I must say though, the scrolling was much smoother when I was drawing the image manually with Graphics.DrawImage().

I might go back to that.

[MrPolite]

Originally posted by wossname
Never mind, I've got it working.

I must say though, the scrolling was much smoother when I was drawing the image manually with Graphics.DrawImage().

I might go back to that.

hehe why was it smoother?
care to post your code so I see what you're doing?