By default, the OwnerDrawPart property is 0. The control fires the OwnerDrawStart and OwnerDrawEnd events when the control requires drawing the owner draw part. These events are fired only for visible parts, that have the OwnerDrawPart property on True. The VisiblePart or VisibleParts property specifies the part being visible or hidden. For instance, the VisiblePart(exLeftB1Part or exLeftB2Part) = True adds two new buttons left/up to the control.

The control paints the parts in the following order ( only if visible ):

• exBackgroundPart
• exLowerBackPart
• exUpperBackPart
• exLeftBPart.
• exLeftB1Part
• exLeftB2Part
• exLeftB3Part
• exLeftB4Part
• exLeftB5Part
• exRightBPart
• exRightB1Part
• exRightB2Part
• exRightB3Part
• exRightB4Part
• exRightB5Part
• exRightB6Part

For instance, the following VB sample draws the lower part in red, and the upper part in green ( as in the screen shot ) :

With ScrollBar1
    .OwnerDrawPart(exLowerBackPart Or exUpperBackPart) = True
End With

Private Type RECT
        Left As Long
        Top As Long
        Right As Long
        Bottom As Long
End Type
Private Declare Function GetClipBox Lib "gdi32" (ByVal hdc As Long, lpRect As RECT) As Long
Private Declare Function FillRect Lib "user32" (ByVal hdc As Long, lpRect As RECT, ByVal hBrush As Long) As Long
Private Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Long) As Long
Private Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long

Private Sub ScrollBar1_OwnerDrawEnd(ByVal Part As EXSCROLLBARLibCtl.PartEnum, ByVal hdc As Long)
    Dim r As RECT, h As Long
    GetClipBox hdc, r
    r.Left = r.Left + 4
    r.Right = r.Right - 4
    If Part = exLowerBackPart Then
        h = CreateSolidBrush(RGB(255, 0, 0))
        FillRect hdc, r, h
        DeleteObject (h)
    Else
        If Part = exUpperBackPart Then
            h = CreateSolidBrush(RGB(0, 255, 0))
            FillRect hdc, r, h
            DeleteObject (h)
        End If
    End If
End Sub

The following C++ sample draws the lower part in red, and the upper part in green ( as in the screen shot ) :

m_scrollbar.SetOwnerDrawPart( 128 /*exUpperBackPart*/,  TRUE );
m_scrollbar.SetOwnerDrawPart( 512 /*exLowerBackPart*/,  TRUE );

void OnOwnerDrawEndScrollbar1(long Part, long hDC) 
{
	HDC h = (HDC)hDC;
	RECT rtPart = {0}; GetClipBox( h, &rtPart );
	InflateRect( &rtPart, -4, 0 );
	switch ( Part )
	{
		case 128: /*exUpperBackPart*/
		{
			HBRUSH hB = CreateSolidBrush( RGB(0,255,0) );
			FillRect( h, &rtPart, hB );
			DeleteObject( hB );
			break;
		}
		case 512: /*exLowerBackPart*/
		{
			HBRUSH hB = CreateSolidBrush( RGB(255,0,0) );
			FillRect( h, &rtPart, hB );
			DeleteObject( hB );
			break;
		}
	}
}