Размещение объектов в NC (Non-Client Area). Кнопка на заголовке

Imports WindowsApplication1.Dwm Imports WindowsApplication1.WinApi Imports WindowsApplication1.NcRender Imports System Imports System.Collections.Generic Imports System.ComponentModel Imports System.Data Imports System.Drawing Imports System.Text Imports System.Windows.Forms Imports System.Runtime.InteropServices Imports System.Diagnostics Imports System.Drawing.Drawing2D  Public Class Form1  #Region "Fields"     Private dwmMargins As Dwm.MARGINS     Private _marginOk As Boolean     Private _aeroEnabled As Boolean #End Region #Region "Ctor"     Public Sub New()         SetStyle(ControlStyles.ResizeRedraw, True)          InitializeComponent()          DoubleBuffered = True          CheckGlassEnabled()     End Sub #End Region #Region "Props"     Public ReadOnly Property AeroEnabled() As Boolean         Get             Return _aeroEnabled         End Get     End Property #End Region #Region "Methods"     ''' <summary>     ''' Sets the value of AeroEnabled     ''' </summary>     Private Sub CheckGlassEnabled()         If Environment.OSVersion.Version.Major >= 6 Then             Dim enabled As Integer = 0             Dim response As Integer = Dwm.dwmIsCompositionEnabled(enabled)              _aeroEnabled = enabled = 1         End If     End Sub     ''' <summary>     ''' Equivalent to the LoWord C Macro     ''' </summary>     ''' <param name="dwValue"></param>     ''' <returns></returns>     Public Shared Function LoWord(ByVal dwValue As Integer) As Integer         Return dwValue And &HFFFF     End Function     ''' <summary>     ''' Equivalent to the HiWord C Macro     ''' </summary>     ''' <param name="dwValue"></param>     ''' <returns></returns>     Public Shared Function HiWord(ByVal dwValue As Integer) As Integer         Return (dwValue >> 16) And &HFFFF     End Function #End Region      Private Sub Form1_Activated(ByVal sender As Object, _                 ByVal e As System.EventArgs) Handles Me.Activated          Dwm.DwmExtendFrameIntoClientArea(Me.Handle, dwmMargins)     End Sub      Private Sub Form1_Paint(ByVal sender As Object, _                             ByVal e As System.Windows.Forms.PaintEventArgs) _                             Handles Me.Paint         If _aeroEnabled Then             e.Graphics.Clear(Color.Transparent)         Else             e.Graphics.Clear(Color.FromArgb(&HC2, &HD9, &HF7))         End If          e.Graphics.FillRectangle(SystemBrushes.ButtonFace, _                                  Rectangle.FromLTRB(dwmMargins.cxLeftWidth - 0, _                                  dwmMargins.cyTopHeight - 0, _                                  Width - dwmMargins.cxRightWidth - 0, _                                  Height - dwmMargins.cyBottomHeight - 0))     End Sub      Protected Overloads Overrides Sub WndProc(ByRef m As Message)         Dim WM_NCCALCSIZE As Integer = &H83         Dim WM_NCHITTEST As Integer = &H84         Dim result As IntPtr          Dim dwmHandled As Integer = Dwm.DwmDefWindowProc(m.HWnd, m.Msg, _                                     m.WParam, m.LParam, result)          If dwmHandled = 1 Then             m.Result = result             Exit Sub         End If          If m.Msg = WM_NCCALCSIZE AndAlso CInt(m.WParam) = 1 Then             Dim nccsp As NCCALCSIZE_PARAMS = _               DirectCast(Marshal.PtrToStructure(m.LParam, _               GetType(NCCALCSIZE_PARAMS)), NCCALCSIZE_PARAMS)              ' Adjust (shrink) the client rectangle to accommodate the border:             nccsp.rect0.Top += 0             nccsp.rect0.Bottom += 0             nccsp.rect0.Left += 0             nccsp.rect0.Right += 0              If Not _marginOk Then                 'Set what client area would be for passing to DwmExtendIntoClientArea                 dwmMargins.cyTopHeight = nccsp.rect2.Top - nccsp.rect1.Top                 dwmMargins.cxLeftWidth = nccsp.rect2.Left - nccsp.rect1.Left                 dwmMargins.cyBottomHeight = nccsp.rect1.Bottom - nccsp.rect2.Bottom                 dwmMargins.cxRightWidth = nccsp.rect1.Right - nccsp.rect2.Right                 _marginOk = True             End If              Marshal.StructureToPtr(nccsp, m.LParam, False)              m.Result = IntPtr.Zero         ElseIf m.Msg = WM_NCHITTEST AndAlso CInt(m.Result) = 0 Then             m.Result = HitTestNCA(m.HWnd, m.WParam, m.LParam)         Else             MyBase.WndProc(m)         End If     End Sub      Private Function HitTestNCA(ByVal hwnd As IntPtr, ByVal wparam _                                       As IntPtr, ByVal lparam As IntPtr) As IntPtr         Dim HTNOWHERE As Integer = 0         Dim HTCLIENT As Integer = 1         Dim HTCAPTION As Integer = 2         Dim HTGROWBOX As Integer = 4         Dim HTSIZE As Integer = HTGROWBOX         Dim HTMINBUTTON As Integer = 8         Dim HTMAXBUTTON As Integer = 9         Dim HTLEFT As Integer = 10         Dim HTRIGHT As Integer = 11         Dim HTTOP As Integer = 12         Dim HTTOPLEFT As Integer = 13         Dim HTTOPRIGHT As Integer = 14         Dim HTBOTTOM As Integer = 15         Dim HTBOTTOMLEFT As Integer = 16         Dim HTBOTTOMRIGHT As Integer = 17         Dim HTREDUCE As Integer = HTMINBUTTON         Dim HTZOOM As Integer = HTMAXBUTTON         Dim HTSIZEFIRST As Integer = HTLEFT         Dim HTSIZELAST As Integer = HTBOTTOMRIGHT          Dim p As New Point(LoWord(CInt(lparam)), HiWord(CInt(lparam)))          Dim topleft As Rectangle = RectangleToScreen(New Rectangle(0, 0, _                                    dwmMargins.cxLeftWidth, dwmMargins.cxLeftWidth))          If topleft.Contains(p) Then             Return New IntPtr(HTTOPLEFT)         End If          Dim topright As Rectangle = _           RectangleToScreen(New Rectangle(Width - dwmMargins.cxRightWidth, 0, _           dwmMargins.cxRightWidth, dwmMargins.cxRightWidth))          If topright.Contains(p) Then             Return New IntPtr(HTTOPRIGHT)         End If          Dim botleft As Rectangle = _            RectangleToScreen(New Rectangle(0, Height - dwmMargins.cyBottomHeight, _            dwmMargins.cxLeftWidth, dwmMargins.cyBottomHeight))          If botleft.Contains(p) Then             Return New IntPtr(HTBOTTOMLEFT)         End If          Dim botright As Rectangle = _             RectangleToScreen(New Rectangle(Width - dwmMargins.cxRightWidth, _             Height - dwmMargins.cyBottomHeight, _             dwmMargins.cxRightWidth, dwmMargins.cyBottomHeight))          If botright.Contains(p) Then             Return New IntPtr(HTBOTTOMRIGHT)         End If          Dim top As Rectangle = _             RectangleToScreen(New Rectangle(0, 0, Width, dwmMargins.cxLeftWidth))          If top.Contains(p) Then             Return New IntPtr(HTTOP)         End If          Dim cap As Rectangle = _             RectangleToScreen(New Rectangle(0, dwmMargins.cxLeftWidth, _             Width, dwmMargins.cyTopHeight - dwmMargins.cxLeftWidth))          If cap.Contains(p) Then             Return New IntPtr(HTCAPTION)         End If          Dim left As Rectangle = _             RectangleToScreen(New Rectangle(0, 0, dwmMargins.cxLeftWidth, Height))          If left.Contains(p) Then             Return New IntPtr(HTLEFT)         End If          Dim right As Rectangle = _             RectangleToScreen(New Rectangle(Width - dwmMargins.cxRightWidth, _             0, dwmMargins.cxRightWidth, Height))          If right.Contains(p) Then             Return New IntPtr(HTRIGHT)         End If          Dim bottom As Rectangle = _             RectangleToScreen(New Rectangle(0, Height - dwmMargins.cyBottomHeight, _             Width, dwmMargins.cyBottomHeight))          If bottom.Contains(p) Then             Return New IntPtr(HTBOTTOM)         End If          Return New IntPtr(HTCLIENT)     End Function  End Class