DragControlP

Private Type POINTAPI
X As Long
Y As Long
End Type
Private Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Private Declare Function ClipCursor Lib "user32" (lpRect As RECT) As Long
Private Declare Function ClipCursorByNum Lib "user32" Alias "ClipCursor" (ByVal _
lpRect As Long) As Long
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Long) As _
Integer
Private Declare Function GetClientRect Lib "user32" (ByVal hwnd As Long, _
lpRect As RECT) As Long
Private Declare Function ClientToScreen Lib "user32" (ByVal hwnd As Long, _
lpPoint As POINTAPI) As Long
Private Declare Function InvalidateRect Lib "user32" (ByVal hwnd As Long, _
lpRect As RECT, ByVal bErase As Long) As Long
Private Declare Function InvalidateRectByNum Lib "user32" Alias _
"InvalidateRect" (ByVal hwnd As Long, ByVal lpRect As Long, _
ByVal bErase As Long) As Long
' Drag a control until the user releases all mouse buttons

'

' You should call this routine from the MouseDown event procedures

' of the controls that you want to make draggable, after

' you determine that the user has initiated a drag operation.

' For example, if you want to let the user drag controls

' using the Ctrl+Right button combination, add this code

' to their MouseDown procedure:

'

' Private Sub Command1_MouseDown(...)

' If Button = vbRightButton And Shift = vbCtrlMask Then

' DragControl Command1

' End If

' End Sub

'

' From that point on, this procedure takes the control and

' exits only when the user releases all mouse buttons

Sub DragControl(ctrl As Control)
Dim startButton As Integer
Dim startPoint As POINTAPI
Dim currPoint As POINTAPI
Dim contRect As RECT
Dim contScaleMode As Integer

' get mouse position and buttons pressed

GetCursorPos startPoint
If GetAsyncKeyState(vbLeftButton) Then startButton = vbLeftButton
If GetAsyncKeyState(vbRightButton) Then startButton = startButton Or _
vbRightButton
If GetAsyncKeyState(vbMiddleButton) Then startButton = startButton Or _
vbMiddleButton

' get container upper-left corner position

' in screen coordinates (currPoint is Zero)

ClientToScreen ctrl.Container.hwnd, currPoint
' get container size

GetClientRect ctrl.Container.hwnd, contRect
' convert to screen coordintes

contRect.Left = currPoint.X
contRect.Top = currPoint.Y
contRect.Right = contRect.Right + currPoint.X
contRect.Bottom = contRect.Bottom + currPoint.Y
' limit the cursor within the parent control

ClipCursor contRect

' get the ScaleMode that is active for the control

' this is the ScaleMode of its container, or it

' is vbTwips if its container does not support

' the ScaleMode property

On Error Resume Next
contScaleMode = vbTwips
' ignore next assignement if the container

' dows not support ScaleMode property

contScaleMode = ctrl.Container.ScaleMode

Do
' exit if all mouse buttons are released

If (startButton And vbLeftButton) = 0 Or GetAsyncKeyState(vbLeftButton) _
= 0 Then
If (startButton And vbRightButton) = 0 Or GetAsyncKeyState _
(vbRightButton) = 0 Then
If (startButton And vbMiddleButton) = 0 Or GetAsyncKeyState _
(vbMiddleButton) = 0 Then
Exit Do
End If
End If
End If

' get current mouse position

GetCursorPos currPoint

' move the control if they are different

If currPoint.X <> startPoint.X Or currPoint.Y <> startPoint.Y Then
' move the control

With ctrl.Parent
ctrl.Move ctrl.Left + .ScaleX(currPoint.X - startPoint.X, _
vbPixels, contScaleMode), ctrl.Top + .ScaleY(currPoint.Y - _
startPoint.Y, vbPixels, contScaleMode)
' refresh container

InvalidateRectByNum .hwnd, 0, False
.Refresh
End With
LSet startPoint = currPoint
End If

' allow background processing

DoEvents
Loop

' restore full mouse movement

ClipCursorByNum 0
End Sub