Make Transparent Forms


To see the effect, add some controls to your form (Lables, Command Buttons, Text Boxes etc.)

Module Code

Option Explicit

Private Declare Function CreateRectRgn Lib "gdi32" (ByVal X1 As Long, _
ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long) As Long
Private Declare Function CombineRgn Lib "gdi32" (ByVal hDestRgn As _
Long, ByVal hSrcRgn1 As Long, ByVal hSrcRgn2 As Long, ByVal _
nCombineMode As Long) As Long
Private Declare Function SetWindowRgn Lib "user32" (ByVal hWnd As _
Long, ByVal hRgn As Long, ByVal bRedraw As Long) As Long

Public Sub TransparentForm(frm As Form)
    frm.ScaleMode = vbPixels
    Const RGN_DIFF = 4
    Const RGN_OR = 2

    Dim outer_rgn As Long
    Dim inner_rgn As Long
    Dim wid As Single
    Dim hgt As Single
    Dim border_width As Single
    Dim title_height As Single
    Dim ctl_left As Single
    Dim ctl_top As Single
    Dim ctl_right As Single
    Dim ctl_bottom As Single
    Dim control_rgn As Long
    Dim combined_rgn As Long
    Dim ctl As Control

    If frm.WindowState = vbMinimized Then Exit Sub

    ' Create the main form region.
    wid = frm.ScaleX(frm.Width, vbTwips, vbPixels)
    hgt = frm.ScaleY(frm.Height, vbTwips, vbPixels)
    outer_rgn = CreateRectRgn(0, 0, wid, hgt)

    border_width = (wid - frm.ScaleWidth) / 2
    title_height = hgt - border_width - frm.ScaleHeight
    inner_rgn = CreateRectRgn(border_width, title_height, wid - border_width, _
        hgt - border_width)

    ' Subtract the inner region from the outer.
    combined_rgn = CreateRectRgn(0, 0, 0, 0)
    CombineRgn combined_rgn, outer_rgn, inner_rgn, RGN_DIFF

    ' Create the control regions.
For Each ctl In frm.Controls
        If ctl.Container Is frm Then
            ctl_left = frm.ScaleX(ctl.Left, frm.ScaleMode, vbPixels) _
                + border_width
            ctl_top = frm.ScaleX(ctl.Top, frm.ScaleMode, vbPixels) + title_height
            ctl_right = frm.ScaleX(ctl.Width, frm.ScaleMode, vbPixels) + ctl_left
            ctl_bottom = frm.ScaleX(ctl.Height, frm.ScaleMode, vbPixels) + ctl_top
            control_rgn = CreateRectRgn(ctl_left, ctl_top, ctl_right, ctl_bottom)
            CombineRgn combined_rgn, combined_rgn, control_rgn, RGN_OR
        End If
    Next ctl

    'Restrict the window to the region.
SetWindowRgn frm.hWnd, combined_rgn, True
End Sub

Form Code

Private Sub Form_Resize()
    TransparentForm Me
End Sub

Go Back