Resizing a picturebox using scroll bars

[dablyz]

Hi there.

Im currently trying to design a project, that loads local images using a dialog box, puts them in a picture box, and changes the height and width, based on the values of scroll bars. The code that calls the loaded image to the picture box is

picBox.Image = Image.FromFile(.FileName)

Im just stuck on where to go from here!

This is just a small part of the project, ive done the rest, but im just stuck on this particular part, and i cant figure it out.
Does anyone have any ideas/links to code that will help me do this?

TIA

Sam

[balabaster]

Hi there.

Im currently trying to design a project, that loads local images using a dialog box, puts them in a picture box, and changes the height and width, based on the values of scroll bars. The code that calls the loaded image to the picture box is

picBox.Image = Image.FromFile(.FileName)

Im just stuck on where to go from here!

This is just a small part of the project, ive done the rest, but im just stuck on this particular part, and i cant figure it out.
Does anyone have any ideas/links to code that will help me do this?

TIA

Sam

Well I'm going to assume that you already know how to programatically change the size of your picture box by setting it's height and width properties...and the picture size within the picture box using the SizeMode property to set how the picture is sized within the image box...so it's really just a case of finding a control that will allow you to graphically scroll up and down to change the size of the picture box control...

So dump an HScrollbar (or a VScrollbar) onto your form and size it accordingly...as you drag this in realtime, the value will change. You'll obviously need one for height and one for width....so maybe an HScrollbar to set the width and a VScrollbar to set the height.

In the scrollbar scroll events you would set: PictureBox1.Width = e.NewValue or PictureBox1.Height = e.NewValue (depending on which scrollbar you're handling the event for).

Hope that helps

[dablyz]

Hi,

Thanks very much for your reply, it did set some wheels in motion!

However, i have set up the scroll bars to adjust height and width respectively - but when the image is loaded into the box by the user, the scroll bars dont seem to adjust the box size at all, i just get a flickering over the image as i move the values along. It seems almost as if i havent set a property right, but im sure i have!

Also, if i can, one further question - when the image gets resized by picturebox - does the actual jpeg get resized, or does it just scale down to fit? ideally, i have to enable my user to resize the image at runtime, and then have the new dimensions displayed in a labe. (although, i dont need to be able to save the resized image, just show it)

Heres hopeing you can help me again!

Thanks

Sam

[balabaster]

Hi,

Thanks very much for your reply, it did set some wheels in motion!

However, i have set up the scroll bars to adjust height and width respectively - but when the image is loaded into the box by the user, the scroll bars dont seem to adjust the box size at all, i just get a flickering over the image as i move the values along. It seems almost as if i havent set a property right, but im sure i have!

Also, if i can, one further question - when the image gets resized by picturebox - does the actual jpeg get resized, or does it just scale down to fit? ideally, i have to enable my user to resize the image at runtime, and then have the new dimensions displayed in a labe. (although, i dont need to be able to save the resized image, just show it)

Heres hopeing you can help me again!

Thanks

Sam

Are you using the right event? I created a demo form with a picture box and a vertical scrollbar. On double clicking the scrollbar the stub for the scroll event will be created...enter the code as follows:
VB

 
Private Sub VScrollBar1_Scroll(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ScrollEventArgs) Handles VScrollBar1.Scroll
PictureBox1.Height = e.NewValue
End Sub

Obviously you need to set the maximum values and the minimum values on your scrollbar to the max/min sizes you want your picture box to be. You would need to follow the same procedure for the width.

Hope that helps.

[dablyz]

Are you using the right event? I created a demo form with a picture box and a vertical scrollbar. On double clicking the scrollbar the stub for the scroll event will be created...enter the code as follows:
VB

 
Private Sub VScrollBar1_Scroll(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ScrollEventArgs) Handles VScrollBar1.Scroll
PictureBox1.Height = e.NewValue
End Sub

Obviously you need to set the maximum values and the minimum values on your scrollbar to the max/min sizes you want your picture box to be. You would need to follow the same procedure for the width.

Hope that helps.

Hi

Looking at it, that did help, as before i had forgotten to adjust the max size of my scroll bars - which seems a bit obvious now!

one more last quick question, lol, if it isnt too much...

With picture boxes, is there any way i can call the current size (that has baan adjusted by the user) to a label? This needs to be done to show the user what size their image is - i was planning to do this in pixels. As i have no padding on my textbox, this would just be the actual box size, wouldnt it? Do you know of the code to do this, i have tried to figure it out, but im getting no where!

Thanks once more for your help, it has been invaluable! :D

Sam

[balabaster]

Hi

Looking at it, that did help, as before i had forgotten to adjust the max size of my scroll bars - which seems a bit obvious now!

one more last quick question, lol, if it isnt too much...

With picture boxes, is there any way i can call the current size (that has baan adjusted by the user) to a label? This needs to be done to show the user what size their image is - i was planning to do this in pixels. As i have no padding on my textbox, this would just be the actual box size, wouldnt it? Do you know of the code to do this, i have tried to figure it out, but im getting no where!

Thanks once more for your help, it has been invaluable! :D

Sam

Use the following code in either your picture box resize event or sizechanged event.
VB

SizeTextLabel.Text = CType(sender, PictureBox).Size.ToString

If you need the heights and widths separately (i.e. to apply your own formatting) you can get Size.Width and Size.Height instead of Size.ToString. But I'm lazy so the example only demonstrates the ToString method.

[dablyz]

Use the following code in either your picture box resize event or sizechanged event.
VB

SizeTextLabel.Text = CType(sender, PictureBox).Size.ToString

If you need the heights and widths separately (i.e. to apply your own formatting) you can get Size.Width and Size.Height instead of Size.ToString. But I'm lazy so the example only demonstrates the ToString method.

That worked a treat mate, thank you ever so much! :D

Sam

[balabaster]

That worked a treat mate, thank you ever so much! :D

Sam

No problem, glad I could help.