这是我的项目树：

MRE_WPF
|
--ViewModels
  |
  --MainWindowButtons
    |
    --HomeButtonViewModel.cs
    --UserSettingsButtonViewModel.cs
--MainWindow.xaml
--MainWindow.xaml.cs

主窗口上有三个按钮。

<Window x:Class="MRE_WPF.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:MRE_WPF"
        xmlns:main_window_buttons="clr-namespace:MRE_WPF.ViewModels.MainWindowButtons"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Canvas Height="480" Name="MainCanvas">
        <Button x:Name="homeButton" 
                Height="55" 
                Width="75" 
                Background="#FF334166" 
                Foreground="{x:Null}" 
                FontSize="24" 
                BorderBrush="{x:Null}" 
                FontFamily="Tahoma"
                Canvas.Top="{Binding Path=(main_window_buttons:HomeButtonViewModel.CanvasTop), Mode=TwoWay, RelativeSource={RelativeSource Self}}"
                >
            <TextBlock Text="Home" Foreground="White"/>
        </Button>

        <Button x:Name="userSetingsButton" 
                Height="55"
                Width="75"
                Background="#FF334166"
                Foreground="{x:Null}"
                FontSize="20"
                BorderBrush="{x:Null}"
                FontFamily="Tahoma"
                Canvas.Top="{Binding Path=(main_window_buttons:UserSettingsButtonViewModel.CanvasTop), Mode=TwoWay, RelativeSource={RelativeSource Self}}"
                Canvas.Left="{Binding Path=(main_window_buttons:UserSettingsButtonViewModel.CanvasLeft), Mode=TwoWay, RelativeSource={RelativeSource Self}}"
                >
            <TextBlock Text="User set" Foreground="White"/>
        </Button>

        <Button x:Name="changeButton" 
                Height="55" 
                Width="75" 
                Background="#FF334166" 
                Foreground="{x:Null}" 
                FontSize="20" 
                Click="changeButton_Click" 
                BorderBrush="{x:Null}" 
                FontFamily="Tahoma" 
                Canvas.Top="100"
                Canvas.Left="500">
            <TextBlock Text="Change" Foreground="White"></TextBlock>
        </Button>
    </Canvas>
</Window>

HomeButtonViewModel类：

public class HomeButtonViewModel:INotifyPropertyChanged {
    public event PropertyChangedEventHandler? PropertyChanged;

    private double canvasTop;

    public double CanvasTop {
        get => canvasTop;
        set {
            canvasTop = value;
            OnPropertyChanged(nameof(CanvasTop));
        }
    }

    public void OnPropertyChanged([CallerMemberName] string name = "") =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}

UserSettingsButtonViewModel基本相同：

public class UserSettingsButtonViewModel:INotifyPropertyChanged {
    public event PropertyChangedEventHandler? PropertyChanged;

    private double canvasTop = 102;
    private double canvasLeft = -1;

    public double CanvasTop {
        get => canvasTop;
        set {
            canvasTop = value;
            OnPropertyChanged(nameof(CanvasTop));
        }
    }

    public double CanvasLeft {
        get => canvasLeft;
        set {
            canvasLeft = value;
            OnPropertyChanged(nameof(canvasLeft));
        }
    }

    public void OnPropertyChanged([CallerMemberName] string name = "") =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}

我想更改这些属性点击按钮Change：

private void changeButton_Click(object sender, RoutedEventArgs e) {
    bool mode = !(bool)Settings.Default["mode7"];
    Settings.Default["mode7"] = mode;
    Settings.Default.Save();
    var h = new HomeButtonViewModel() {
        CanvasTop = mode ? 1 : 0
    };
    var us = new UserSettingsButtonViewModel() {
        CanvasTop = mode ? 102 : double.NaN,
        CanvasLeft = mode ? -1 : double.NaN
    };
}

但点击时什么也没发生。我知道我做错了什么，但我不知道是什么。
//我也想使用命令而不是单击，但让我们解决一个问题。