Question

我试图根据绑定的布尔值在组合框列表中显示图像。单击图像时的布尔值，因此图像应该更改。这是xaml：

   <ComboBox Name="Combo2" Margin="20,79,20,0" ItemsSource="{Binding}" VerticalAlignment="Top" Height="20">
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <StackPanel Orientation="Horizontal">
                    <Image Name="MyBoolImage" Height="12" Width="12" MouseLeftButtonUp="Image_MouseLeftButtonUp"/>
                    <TextBlock Text="{Binding name}" Margin="5,0,0,0" Width="100" />
                </StackPanel>
                <DataTemplate.Triggers>
                    <DataTrigger Binding="{Binding LightOn}" Value="False">
                        <Setter TargetName="MyBoolImage" Property="Source" Value="/Images/Exit.png"/>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding LightOn}" Value="True">
                        <Setter TargetName="MyBoolImage" Property="Source" Value="/Images/Cut.png"/>
                    </DataTrigger>
                </DataTemplate.Triggers>
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>

数据类：

Class ComboData

Private _LightOn As Boolean
Public Property LightOn As Boolean
    Get
        Return _LightOn
    End Get
    Set(value As Boolean)
        _LightOn = value
    End Set
End Property

Private _name As String
Public Property name As String
    Get
        Return _name
    End Get
    Set(value As String)
        _name = value
    End Set
End Property

Sub New(name_ As String, Light_On As Boolean)
    _LightOn = Light_On
    _name = name_
End Sub

End Class

加载一些测试数据：

    Dim x As New List(Of ComboData)

    x.Add(New ComboData("test1a", True))
    x.Add(New ComboData("test2a", False))
    x.Add(New ComboData("test3a", True))
    x.Add(New ComboData("test4a", True))
    x.Add(New ComboData("test5a", False))
    x.Add(New ComboData("test6a", True))
    Combo2.ItemsSource = x

最后是魔术未发生的点击事件......

Private Sub Image_MouseLeftButtonUp(sender As Object, e As MouseButtonEventArgs)
    Dim SelectedComboData As ComboData = TryCast(CType(sender, Image).DataContext, ComboData)
    SelectedComboData.LightOn = Not SelectedComboData.LightOn
    e.Handled = True
End Sub

LightOn值按照预期更改，即使在＆＃34; x＆＃34; （combodata列表），值改变了。但显示的图像没有变化。

我错过了什么？

谢谢！

Answer 1

类comboData应实现INotifyPropertyChanged，以便通知UI有关其更改的内容。

Class ComboData
    Implements INotifyPropertyChanged

    Private _LightOn As Boolean
    Public Property LightOn As Boolean
        Get
            Return _LightOn
        End Get
        Set(value As Boolean)
            _LightOn = value
            OnPropertyChanged("LightOn")
        End Set
    End Property

    Private _name As String
    Public Property name As String
        Get
            Return _name
        End Get
        Set(value As String)
            _name = value
            OnPropertyChanged("name")
        End Set
    End Property

    Sub New(name_ As String, Light_On As Boolean)
        _LightOn = Light_On
        _name = name_
    End Sub

    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Protected Sub OnPropertyChanged(propertyName As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propertyName))
    End Sub
End Class

组合框列表中的wpf图像按钮

1 个答案: