WPF

public delegate void LoggingDelegate(string message);

public void LogMessage(string message)
{
}

LoggingDelegate logMessageHandler = LogMessage;
ClassB.SomeMethod(logMessageHandler);

public void SomeMethod(Delegate logDelegate)
{
   logDelegate.    //<=== Nothing here. Shouldn't I be seeing the LogMessage method signature?
}

<CheckBox IsChecked="{Binding SelectedProcess.Enabled}"
            IsEnabled="{Binding AllowProcessEdit}"
            x:Name="EnabledCheckbox"
            Foreground="Black"
            FontSize="12"
            Margin="10,0,0,0"
            VerticalAlignment="Center"
            HorizontalAlignment="Stretch"/>

<TextBlock Grid.Row="4"
            Foreground="Red"
            FontWeight="Bold"
            FontSize="12"
            VerticalAlignment="Center"
            HorizontalAlignment="Right"
            Text="This process is disabled"
            Margin="10,0,0,0">
                                    
    <TextBlock.Style>
        <Style>
            <Style.Triggers>
                <DataTrigger Binding="{Binding SelectedProcess}" Value="Null">
                    <Setter Property="UIElement.Visibility" Value="Hidden"/>
                </DataTrigger>
                <DataTrigger Binding="{Binding SelectedProcess.Enabled}" Value="True">
                    <Setter Property="UIElement.Visibility" Value="Hidden"/>
                </DataTrigger>
                <DataTrigger Binding="{Binding SelectedProcess.Enabled}" Value="False">
                    <Setter Property="UIElement.Visibility" Value="Visible"/>
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </TextBlock.Style>
</TextBlock>

private bool _IsHourlyMinutesFocused;
public bool IsHourlyMinutesFocused
{
    get { return _IsHourlyMinutesFocused; }
    set
    {
        if (_IsHourlyMinutesFocused != value)
        {
            _IsHourlyMinutesFocused = value;
            RaisePropertyChanged("IsHourlyMinutesFocused");
        }
    }
}

<TextBox Grid.Row="0"
        Grid.Column="2"
        VerticalAlignment="Center"
        classes:FocusExtension.IsFocused="{Binding IsHourlyMinutesFocused}" 
        Focusable="True"
        Text="{Binding SelectedProcess.ProcessSchedule.HourlyMinutes}"
        Margin="2,0,2,0"
        Width="40"/>

<ComboBox IsEditable="True" Text="Language" HorizontalAlignment="Right" VerticalAlignment="Top" Width="95"  Margin="34,21,34,0" ItemsSource="{Binding Languages}" SelectedItem="{Binding SelectedLanguage, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Foreground="#FF434C64" removed="Green" Height="24.96"  />

public void ChangeLanguage()
         {
             if (SelectedLanguage == "en")
             {
                 Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo("en");

             }
             else
             if (SelectedLanguage == "it-IT")
             {
                 Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo("it-IT");
             }

         }

public ViewModel()
       {

           LoadData();
           ChangeLanguage();

           Login = new DelegateCommand(this.Logging, delegate()
           {
               return (!String.IsNullOrEmpty(Username) && !String.IsNullOrEmpty(Password) && !String.IsNullOrEmpty(Email));
           });
           Register = new DelegateCommand(this.Registering, delegate()
           {

          return (!String.IsNullOrEmpty(Username) && !String.IsNullOrEmpty(Password) && !String.IsNullOrEmpty(Email));



       });

<TreeView>
    <TreeViewItem Header="Category" ItemsSource="{Binding Categories}" />
    <TreeViewItem Header="Colors" ItemsSource="{Binding Colors}" />
</TreeView>