带圆角的 WPF 无边框应用程序

Question

我创建了一个无边框的 WPF 应用程序，并且有一个我想作为背景的图像。我在“画图”中创建了图像，因此无法选择使角透明。我想让应用程序具有圆角，但我没有通过 XAML 获得预期结果。我尝试添加边框以获得所需的效果，但是当我运行应用程序时，图像仍然位于边框前面。这是我的代码。我做错了什么？

<Border BorderBrush="Black" CornerRadius="15,15,15,15" BorderThickness="1,1,1,1" Width="242" Height="426">
    <Grid>
        <Image Height="425" Name="image1" Stretch="Fill" Width="240" Source="/Test;component/Test.png" />
        <Grid Height="334" HorizontalAlignment="Left" Margin="24,39,0,0" Name="grid1" VerticalAlignment="Top" Width="198" />
    </Grid>
</Border>

Answer 1

窗口中的这些设置将使其透明：

WindowStyle="None"
AllowsTransparency="True"
Background="Transparent"

然后将边框的背景设置为图像：

  <Border BorderBrush="Transparent" BorderThickness="1" CornerRadius="15">
            <Border.Background>
                <ImageBrush>
                    <ImageBrush.ImageSource>
                <BitmapImage UriSource="/Test;component/Test.png" />
                    </ImageBrush.ImageSource>
                </ImageBrush>
            </Border.Background>
        </Border>

Answer 2

我认为您需要将 ClipToBounds="True" 添加到图像中。

Answer 3

这是一个特殊的边框，ClipToBounds 可以完美地工作。如果您将埃雷兹的答案中的“Border”更改为“ClippingBorder”，那么它应该可以工作。

''' <Remarks>
'''     As a side effect ClippingBorder will surpress any databinding or animation of 
'''         its childs UIElement.Clip property until the child is removed from ClippingBorder
''' </Remarks>

Public Class ClippingBorder
Inherits Border
Protected Overrides Sub OnRender(ByVal dc As DrawingContext)
    OnApplyChildClip()
    MyBase.OnRender(dc)
End Sub

Public Overrides Property Child() As UIElement
    Get
        Return MyBase.Child
    End Get
    Set(ByVal value As UIElement)
        If Me.Child IsNot value Then
            If Me.Child IsNot Nothing Then
                ' Restore original clipping
                Me.Child.SetValue(UIElement.ClipProperty, _oldClip)
            End If

            If value IsNot Nothing Then
                _oldClip = value.ReadLocalValue(UIElement.ClipProperty)
            Else
                ' If we dont set it to null we could leak a Geometry object
                _oldClip = Nothing
            End If
            MyBase.Child = value
        End If
    End Set
End Property

Protected Overridable Sub OnApplyChildClip()
    Dim _child As UIElement = Me.Child
    If _child IsNot Nothing Then
        _clipRect.RadiusX = InlineAssignHelper(_clipRect.RadiusY, Math.Max(0.0, Me.CornerRadius.TopLeft - (Me.BorderThickness.Left * 0.5)))
        _clipRect.Rect = New Rect(_child.RenderSize)
        _child.Clip = _clipRect
    End If
End Sub

Private _clipRect As New RectangleGeometry()
Private _oldClip As Object
Private Shared Function InlineAssignHelper(Of T)(ByRef target As T, ByVal value As T) As T
    target = value
    Return value
End Function

End Class

您可以使用 http://www.developerfusion.com/tools/convert/ vb-to-csharp/ 如果您更喜欢 C#。