Question

我创建了一个自定义按钮，上面有一个布尔标志，表示它是否被选中。如果选中它，我想更改按钮的背景颜色，以便用户可以快速了解他们正在查看的控件。问题是我无法让触发器正常工作。我在这里看到的一切，我已经尝试但在代码的InitializeComponent部分仍然出现错误。

以下是我正在处理的属性

Private mIsSelected As Boolean = False
Public Property IsSelected() As Boolean
    Get
        Return mIsSelected
    End Get
    Set(ByVal value As Boolean)
        mIsSelected = value
    End Set
End Property


Public Shared ReadOnly MyBackgroundProperty As DependencyProperty = DependencyProperty.Register("MyBackground",
                                                                                                GetType(LinearGradientBrush), GetType(RentAdjButtons),
                                                                                                    New PropertyMetadata(New LinearGradientBrush(ColorConverter.ConvertFromString("#3366CC"), ColorConverter.ConvertFromString("#0000FF"), New System.Windows.Point(0.5, 0), New System.Windows.Point(0.5, 1))))


Private mMyBackground As New LinearGradientBrush
Public Property MyBackground() As LinearGradientBrush
    Get
        Return mMyBackground
    End Get
    Set(ByVal value As LinearGradientBrush)
        mMyBackground = value
    End Set
End Property

这是我的XMAL

 <Style TargetType="Com:RentAdjButtons">
            <Setter Property="MyBackground" Value="{StaticResource DefaultBackground}" />
            <Style.Triggers>
                <Trigger Property="IsSelected" Value="True">
                    <Setter Property="MyBackground" Value="{StaticResource SelectedButton}" />
                </Trigger>
            </Style.Triggers>
       </Style>

目前我得到的错误是“触发器上的属性不能为空”

提前感谢您的任何帮助

Answer 1

您可以使用默认情况下具有此属性的ToggleButton。

Answer 2

Trigger.Property必须是DependencyProperty才能使触发器正常工作。有关文档，请参阅MSDN。您需要将类属性IsSelected更改为DependencyProperty。

此外，MyBackground的getter / setter应该使用SetValue和GetValue {/ 3}}在MSDN中进行定义：

    Public Property State() As Boolean
      Get
          Return CType(Me.GetValue(StateProperty), Boolean)
      End Get
      Set(ByVal value As Boolean)
          Me.SetValue(StateProperty, value)
      End Set
    End Property
    Public Shared ReadOnly StateProperty As DependencyProperty = 
      DependencyProperty.Register("State", GetType(Boolean), GetType(MyStateControl),
      New PropertyMetadata(False))

设置自定义属性WPF的触发器

2 个答案: