Alpha Blend Form - Com Controles

[ricarmpo]

Fala ai galera beleza ?

Estou com um problema, estou tentando colocar controles (Buttons, TextBox, etc) em um Layered Form, já pesquisei bastante mais ainda nada de funcionar.

Criei um form que utiliza um PNG com trasnparencia como background, a parte do PNG e da transparencia funciona perfeito,

porem não consigo adicionar controles nesse form.

alguém pode ajudar ?

Se existir outra maneira de fazer o PNG com a transparencia funcionar e tiver como adicionar controles no form, por favor postem, realmente preciso disso.

Tks

#Region "Importando a API GDI"

Public Class Win32
    Public Enum Bool
        [False] = 0
        [True] = 1
    End Enum 'Bool

    Public Structure Point
        Public x As Int32
        Public y As Int32

        Public Sub New(ByVal x As Int32, ByVal y As Int32)
            Me.x = x
            Me.y = y
        End Sub 'New
    End Structure 'Point

    Public Structure Size
        Public cx As Int32
        Public cy As Int32

        Public Sub New(ByVal cx As Int32, ByVal cy As Int32)
            Me.cx = cx
            Me.cy = cy
        End Sub 'New
    End Structure 'Size

    Structure ARGB
        Public Blue As Byte
        Public Green As Byte
        Public Red As Byte
        Public Alpha As Byte
    End Structure 'ARGB

    Public Structure BLENDFUNCTION
        Public BlendOp As Byte
        Public BlendFlags As Byte
        Public SourceConstantAlpha As Byte
        Public AlphaFormat As Byte
    End Structure 'BLENDFUNCTION


    Public Shared ULW_COLORKEY As Int32 = &H1
    Public Shared ULW_ALPHA As Int32 = &H2
    Public Shared ULW_OPAQUE As Int32 = &H4

    Public Shared AC_SRC_OVER As Byte = &H0
    Public Shared AC_SRC_ALPHA As Byte = &H1

    Public Declare Function UpdateLayeredWindow Lib "user32" Alias "UpdateLayeredWindow" (ByVal hwnd As IntPtr, ByVal hdcDst As IntPtr, ByRef pptDst As Point, ByRef psize As Size, ByVal hdcSrc As IntPtr, ByRef pprSrc As Point, ByVal crKey As Int32, ByRef pblend As BLENDFUNCTION, ByVal dwFlags As Int32) As Boolean
    Public Declare Function GetDC Lib "user32" Alias "GetDC" (ByVal hWnd As IntPtr) As IntPtr
    Public Declare Function ReleaseDC Lib "user32" Alias "ReleaseDC" (ByVal hWnd As IntPtr, ByVal hDC As IntPtr) As Integer
    Public Declare Function CreateCompatibleDC Lib "gdi32.dll" Alias "CreateCompatibleDC" (ByVal hDC As IntPtr) As IntPtr
    Public Declare Function DeleteDC Lib "gdi32.dll" Alias "DeleteDC" (ByVal hDC As IntPtr) As Boolean
    Public Declare Function SelectObject Lib "gdi32.dll" Alias "SelectObject" (ByVal hDC As IntPtr, ByVal hObject As IntPtr) As IntPtr
    Public Declare Function DeleteObject Lib "gdi32.dll" Alias "DeleteObject" (ByVal hObject As IntPtr) As Boolean
End Class

#End Region



'Para funcionar o PNG com trasparencia, chamar a sub LoadBackground no formload

Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Windows.Forms
Imports Common.Win32

Public Class MainForm
    Protected Overrides ReadOnly Property CreateParams() As CreateParams
        Get
            Dim cp As CreateParams = MyBase.CreateParams
            If Not Site Is Nothing Then
                If Not Site.DesignMode Then
                    cp.ExStyle = cp.ExStyle Or &H80000
                End If
            Else
                cp.ExStyle = cp.ExStyle Or &H80000
            End If
            Return cp
        End Get
    End Property

    Protected Sub LoadBackground()
        Dim _background As Bitmap = BackgroundImage
        If Not _background Is Nothing Then
            If Not _background.PixelFormat = PixelFormat.Format32bppArgb Then
                MessageBox.Show("The bitmap must be 32bpp with alpha-channel.")
            Else
                Dim screenDc As IntPtr = GetDC(IntPtr.Zero)
                Dim memDc As IntPtr = CreateCompatibleDC(screenDc)
                Dim hBitmap As IntPtr = IntPtr.Zero
                Dim oldBitmap As IntPtr = IntPtr.Zero

                Try
                    hBitmap = _background.GetHbitmap(Color.FromArgb(0))
                    oldBitmap = SelectObject(memDc, hBitmap)
                    Dim size As New Win32.Size(_background.Width, _background.Height)
                    Dim pointSource As New Win32.Point(0, 0)
                    Dim topPos As New Win32.Point(Me.Left, Me.Top)
                    Dim blend As New BLENDFUNCTION
                    blend.BlendOp = AC_SRC_OVER
                    blend.BlendFlags = 0
                    blend.SourceConstantAlpha = 255
                    blend.AlphaFormat = AC_SRC_ALPHA
                    UpdateLayeredWindow(Me.Handle, screenDc, topPos, size, memDc, pointSource, 0, blend, ULW_ALPHA)
                Finally
                    ReleaseDC(IntPtr.Zero, screenDc)
                    If Not hBitmap = IntPtr.Zero Then
                        SelectObject(memDc, oldBitmap)
                        DeleteObject(hBitmap)
                    End If
                    DeleteDC(memDc)
                End Try
            End If
        End If
    End Sub

    Protected Overrides Sub WndProc(ByRef m As Message)
        If m.Msg = &H84 Then
            m.Result = 2
            Return
        End If
        MyBase.WndProc(m)
    End Sub

End Class