Конвертер не вызывается после выполнения команды

Эта кнопка должна переключаться между доступным списком цветов и соответствующим образом изменять цвет фона.

Изначально у меня была эта часть кода модели представления в одной большой / основной модели представления, но я решил разделить ее, чтобы каждый из моих пользовательских элементов управления имел свою собственную модель представления. Я попытался установить точку останова, в которой выполняется метод OnChangeColor (), и я вижу, что состояние действительно меняется, но, похоже, это изменение не сохраняется в преобразователе, который, следовательно, не обновляет цвет фона пользовательского интерфейса вообще.

Я разместил код ниже, в который я внес изменения и в настоящее время работаю, чтобы попытаться выяснить, в чем проблема.

MainWindow

    <Window.DataContext>
    <local:MainWindowViewModel />
</Window.DataContext>
<Window.Resources>
    <DataTemplate DataType = "{x:Type local:CameraListViewModel}">
        <local:MainView />
    </DataTemplate>
    <DataTemplate DataType = "{x:Type rep:ReportViewModel}">
        <rep:ReportView />
    </DataTemplate>
    <DataTemplate DataType = "{x:Type cam:CameraMonitorViewModel}">
        <cam:CameraMonitorView />
    </DataTemplate>
    <DataTemplate DataType = "{x:Type cam:CameraPropertiesViewModel}">
        <cam:CameraPropertiesView />
    </DataTemplate>
</Window.Resources>
<Grid>
    <ContentControl Content = "{Binding CurrentViewModel}" />
</Grid>

Просмотреть модель:

public class CameraPropertiesViewModel : ViewModelBase
{    
    /// <summary>
    /// The current state of the background color
    /// </summary>
    private States _state;

    //Delegate commands for the UI
    private DelegateCommand _changeColorCommand;
    public ICommand ChangeColorCommand
    {
        get
        {
            if (_changeColorCommand == null)
            {
                _changeColorCommand = new DelegateCommand(OnChangeColor);
            }
            return _changeColorCommand;

        }
    }

    //All possible background colors
    public enum States
    {
        GREEN,
        YELLOW,
        RED
    }

    //Gets or sets the background color
    public States State
    {
        get
        {
            return _state;
        }
        set
        {
            SetProperty(ref _state, value);
        }
    }

    //Cycle through different colors
    private void OnChangeColor()
    {
        if (State == States.GREEN)
            State = States.RED;
        else if (State == States.RED)
            State = States.YELLOW;
        else if (State == States.YELLOW)
            State = States.GREEN;
    }

}

Конвертер:

    [ValueConversion(typeof(CameraPropertiesViewModel.States), typeof(Brush))]
public class EnumToColorConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        CameraPropertiesViewModel.States state = (CameraPropertiesViewModel.States)value;

        switch (state)
        {
            case CameraPropertiesViewModel.States.GREEN:
                return new SolidColorBrush(Colors.Green);
            case CameraPropertiesViewModel.States.YELLOW:
                return new SolidColorBrush(Colors.Yellow);
            case CameraPropertiesViewModel.States.RED:
                return new SolidColorBrush(Colors.Red);
        }

        return new SolidColorBrush(Colors.LightGray);
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        return null;
    }
}

MainView

    <UserControl.Resources>
    <conv:EnumToColorConverter x:Key = "enumToColorConvert"/>
    <cam:CameraPropertiesViewModel x:Key = "CPVM" />
</UserControl.Resources>

<Grid Background = "{Binding Path=State, Source = {StaticResource CPVM},  Converter = {StaticResource enumToColorConvert}}">
    <Grid.RowDefinitions>
        <RowDefinition Height = "Auto" />
        <RowDefinition  />
        <RowDefinition Height = "Auto"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition />
        <ColumnDefinition Width = "Auto"/>
    </Grid.ColumnDefinitions>

    <cam:CamerasListView />

    <cam:CameraPropertiesView Grid.Column = "1"/>

    <cam:CameraMonitorView Grid.Row = "1" 
                           Grid.ColumnSpan = "2" />

    <cam:CameraFunctionView Grid.Row = "2" 
                            Grid.ColumnSpan = "2"/>
</Grid>

Ресурсы:

<local:CameraPropertiesViewModel x:Key = "CPVM" />

Кнопка

 <Button Style = "{StaticResource circleButton}"
                    Command = "{Binding ChangeColorCommand, Source = {StaticResource CPVM}}"                     
                    Content = "Change Theme" 
                    Width = "100" 
                    HorizontalAlignment = "Center" 
                    VerticalAlignment = "Center"  
                    Grid.Column = "2"
                    Grid.Row = "2"/>

CameraPropertiesView.xaml

<UserControl.Resources>
    <local:CameraPropertiesViewModel x:Key = "CPVM" />
    <Style TargetType = "{x:Type Button}" x:Key = "circleButton">
        <Setter Property = "Template">
            <Setter.Value>
                <ControlTemplate>
                    <Grid>
                        <Viewbox>
                            <Canvas Width = "50" Height = "50">
                                <Ellipse Fill = "{TemplateBinding Control.Background}" Width = "50" Height = "50"/>
                            </Canvas>
                        </Viewbox>
                        <ContentPresenter VerticalAlignment = "Center" HorizontalAlignment = "Center" Content = "{TemplateBinding Button.Content}"/>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</UserControl.Resources>

<Grid>
    <GroupBox Header = "Camera Details" 
              Height = "130" 
              Width = "386" 
              HorizontalAlignment = "Right" 
              VerticalAlignment = "Top"
              Margin = "10">
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition />
                <RowDefinition />
                <RowDefinition />
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width = "Auto" />
                <ColumnDefinition />
                <ColumnDefinition Width = "120" />
            </Grid.ColumnDefinitions>

            <Label Height = "25" 
                   Width = "70" 
                   Content = "Name" 
                   HorizontalAlignment = "Center" 
                   VerticalAlignment = "Center"
                   HorizontalContentAlignment = "Right" />
            <TextBox Text = "{Binding ConnectedCamera.Name}" 
                     HorizontalAlignment = "Center" 
                     VerticalAlignment = "Center" 
                     Height = "23" 
                     Width = "160"
                     Grid.Column = "1"
                     IsReadOnly = "True" />

            <Label Height = "25" 
                   Width = "70" 
                   Content = "Model" 
                   HorizontalAlignment = "Center" 
                   VerticalAlignment = "Center" 
                   Grid.Row = "1"
                   HorizontalContentAlignment = "Right" />
            <TextBox Text = "{Binding ConnectedCamera.Model}" 
                     HorizontalAlignment = "Center" 
                     VerticalAlignment = "Center" 
                     Height = "23" 
                     Width = "160"
                     IsReadOnly = "True"
                     Grid.Column = "1"
                     Grid.Row = "1" />

            <Label Height = "25" 
                   Width = "70" 
                   Content = "Ip Address" 
                   HorizontalAlignment = "Center" 
                   VerticalAlignment = "Center" 
                   Grid.Row = "2"
                   HorizontalContentAlignment = "Right" />
            <TextBox Text = "{Binding ConnectedCamera.IpAddress}" 
                     HorizontalAlignment = "Center" 
                     VerticalAlignment = "Center" 
                     Height = "23" 
                     Width = "160"
                     IsReadOnly = "True" 
                     Grid.Column = "1"
                     Grid.Row = "2" />

            <Button Command = "{Binding GenerateReportCommand}"
                    Content = "Generate Report" 
                    Width = "100" 
                    HorizontalAlignment = "Center" 
                    VerticalAlignment = "Center"  
                    Grid.Column = "2" />

            <Button Command = "{Binding ArchiveReportCommand}"
                    Content = "Archive Report" 
                    Width = "100" 
                    HorizontalAlignment = "Center" 
                    VerticalAlignment = "Center"  
                    Grid.Column = "2"
                    Grid.Row = "1"/>

            <Button Style = "{StaticResource circleButton}"
                    Command = "{Binding ChangeColorCommand, Source = {StaticResource CPVM}}"                     
                    Content = "Change Theme" 
                    Width = "100" 
                    HorizontalAlignment = "Center" 
                    VerticalAlignment = "Center"  
                    Grid.Column = "2"
                    Grid.Row = "2"/>

        </Grid>
    </GroupBox>
</Grid>