我无法将两个文本框链接到两个类中定义的属性。我测试了这个简单的例子，请问错误在哪里？
我的XAML：

<Window x:Class="MainWindow"

        xmlns:local="clr-namespace:WpfApp_multiBinding" xmlns:multipleviewmodel="clr-namespace:WpfApp_multiBinding.MultipleViewModel" d:DataContext="{d:DesignInstance Type=local:MainWindow}"
        mc:Ignorable="d"
        Title="MainWindow">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="40"/>
            <RowDefinition Height="40"/>
        </Grid.RowDefinitions>
        <StackPanel Grid.Row="0" x:Name="SP1" Orientation="Horizontal" >
            <TextBlock  Text="{Binding ViewModels.ViewMod1.Text1}"/>
        </StackPanel>
        <StackPanel Grid.Row="1" x:Name="SP2" Orientation="Horizontal">
            <TextBlock Text="{Binding ViewModels.ViewMod2.Text2}"/>
        </StackPanel>
    </Grid>
</Window>

字符串
主窗口：

Imports WpfApp_multiBinding.MultipleViewModel
    
    Class MainWindow
            Public ViewModels As ViewModels
    
            Sub New()
                InitializeComponent()
    
                ViewModels = New ViewModels
                DataContext = ViewModels
    
                SP1.DataContext = ViewModels.ViewMod1
                SP2.DataContext = ViewModels.ViewMod2
    
                ViewModels.ViewMod1.Text1 = "toto"
                ViewModels.ViewMod2.Text2 = "titi"
            End Sub
        End Class

型
我的课

Imports System.ComponentModel
    
    Namespace MultipleViewModel
    
        Public Class ViewModels
            Public ViewMod1 As New ViewModel1
            Public ViewMod2 As New ViewModel2
        End Class
    
        Public Class ViewModel1
    
            Implements INotifyPropertyChanged
            Public Event PropertyChanged(sender As Object, e As PropertyChangedEventArgs) Implements INotifyPropertyChanged.PropertyChanged
    
            Public Sub OnPropertyChanged(ByVal e As PropertyChangedEventArgs)
                If PropertyChangedEvent IsNot Nothing Then
                    RaiseEvent PropertyChanged(Me, e)
                End If
            End Sub
    
            Private Property _Text1 As String
    
            Public Property Text1 As String
                Get
                    Return _Text1
                End Get
                Set(value As String)
                    _Text1 = value
                    OnPropertyChanged(New PropertyChangedEventArgs(NameOf(Text1)))
                End Set
            End Property
    
        End Class
    Public Class ViewModel2
... idem Class VieModel1 ...
End Class
    End Namespace

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