Microsoft KB Archive/109741

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Article ID: 109741

Article Last Modified on 7/13/2004



APPLIES TO

  • Microsoft Visual Basic 4.0 16-bit Enterprise Edition
  • Microsoft Visual Basic 4.0 32-Bit Enterprise Edition
  • Microsoft Visual Basic 5.0 Enterprise Edition
  • Microsoft Visual Basic 6.0 Enterprise Edition
  • Microsoft Visual Basic 5.0 Learning Edition
  • Microsoft Visual Basic 6.0 Learning Edition
  • Microsoft Visual Basic 3.0 Professional Edition
  • Microsoft Visual Basic 5.0 Professional Edition
  • Microsoft Visual Basic 6.0 Professional Edition
  • Microsoft Visual Basic 4.0 Professional Edition
  • Microsoft Visual Basic 4.0 Professional Edition
  • Microsoft Visual Basic 3.0 Professional Edition
  • Microsoft Visual Basic 4.0 Standard Edition



This article was previously published under Q109741

SUMMARY

A Visual Basic form cannot be sized larger than the screen. This article explains how to scroll the contents of a form to enlarge the usable area of a form.

The sample program below works by scrolling a picture box control which is larger than the form and contains attached controls. When the picture box scrolls, all the attached controls scroll together.

MORE INFORMATION

Step-by-Step Example

NOTE: This technique will not work on any version of Windows NT if any of the Visual Basic lightweight controls (for example, Label Control) are children of the scrolling control and positioned outside of the screen's viewing area. This is due to the way that Windows NT handles drawing to nonlogical areas of the screen. To work around the problem, do not use lightweight controls as children of the scrolling control.

  1. Start a new project in Visual Basic. Form1 is created by default.
  2. Add a horizontal scroll bar control and a vertical scroll bar control to Form1. (The size doesn't matter because the program automatically sizes the scroll bars in the Form Resize event code.)
  3. Add a picture box control to Form1. Draw a text box control inside the upper-left corner of the picture box such that when the picture box moves, the text box moves with it.

    Select the Text1 box and press the F4 key to display the Properties window. Set the Text1 Index property to 0, which is required at design time to make an array of text controls.

    You can also enhance this sample program by placing more controls into the picture box. When the picture box scrolls, all the controls scroll.
  4. Add the following code to the Form Load event:

          Sub Form_Load()
             ' Make the picture box bigger than the form:
             Picture1.Move 0, 0, 1.4 * ScaleWidth, 1.2 * ScaleHeight
             ' Position and size the first TextBox:
             Text1(0).Move 0, 0, Picture1.Width / 2, Picture1.Height / 20
             ' Place some sample controls in the picture box:
             Dim i As Integer
             For i = 1 To 20
                Load Text1(i)
                Text1(i).Visible = True
                Text1(i).Left = i * Picture1.Height / 20
                Text1(i).Top = Text1(i).Left
             Next
          End Sub
  5. Add the following code to the Form Resize event:

          Sub Form_Resize ()
             ' Position the scroll bars:
             hscroll1.Left = 0
             vscroll1.Top = 0
             If Picture1.Width > scalewidth Then
                hscroll1.Top = ScaleHeight - hscroll1.Height
             Else
                hscroll1.Top = ScaleHeight
             End If
             If Picture1.Height > hscroll1.Top Then
                vscroll1.Left = scalewidth - vscroll1.Width
                If Picture1.Width > vscroll1.Left Then
                   hscroll1.Top = ScaleHeight - hscroll1.Height
                End If
             Else
                vscroll1.Left = scalewidth
             End If
             hscroll1.Width = scalewidth
             If hscroll1.Top > 0 then vscroll1.Height=hscroll1.Top
             ' Set the scroll bar ranges
             hscroll1.Max = Picture1.Width - vscroll1.Left
             vscroll1.Max = Picture1.Height - hscroll1.Top
             hscroll1.SmallChange = Abs(hscroll1.Max \ 16) + 1
             hscroll1.LargeChange = Abs(hscroll1.Max \ 4) + 1
             vscroll1.SmallChange = Abs(vscroll1.Max \ 16) + 1
             vscroll1.LargeChange = Abs(vscroll1.Max \ 4) + 1
             hscroll1.ZOrder 0
             vscroll1.ZOrder 0
          End Sub
  6. Add the following code to the HScroll1 Change event:

          Sub HScroll1_Change ()
             Picture1.Left = -HScroll1.Value
          End Sub
  7. Add the following code to the VScroll1 Change event:

          Sub VScroll1_Change ()
             Picture1.Top = -VScroll1.Value
          End Sub
  8. Start the program (or press the F5 key). Click the scroll bars to scroll the form. Close the form to end the program.



Additional query words: 3.00 4.00 vb416

Keywords: kbhowto KB109741