XAML Expert.NET: Cod C# si XAML (Separarea interfetei grafice de logica aplicatiei)

MainWindow.xaml.cs

namespace SampleWpf
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
}
}

MainWindowViewModel.cs

using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Input;

namespace SampleWpf
{
internal class MainWindowViewModel : INotifyPropertyChanged
{
public MainWindowViewModel() { Mesaje = new ObservableCollection<string>(); }

public string UltimulMesaj
{
get { return _ultimulMesaj; }
private set { _ultimulMesaj = value; InvokePropertyChanged("UltimulMesaj"); }
}
private string _ultimulMesaj;

public string Mesaj
{
get { return _mesaj; }
set { _mesaj = value; InvokePropertyChanged("Mesaj"); }
}
private string _mesaj;

public ObservableCollection<string> Mesaje { get; private set; }

public ICommand AdaugaMesajCommand
{
get
{
return _adaugaMesajCommand ?? (_adaugaMesajCommand = new Command(Execute));
}
}
private ICommand _adaugaMesajCommand;

private void Execute(object commandParam)
{
var mesaj = commandParam as string;
Mesaje.Add(mesaj);
UltimulMesaj = string.Format("Mesaj adaugat: {0}", mesaj);
Mesaj = string.Empty;
}

// Implementeaza membru INotifyPropertyChanged
public event PropertyChangedEventHandler PropertyChanged;

private void InvokePropertyChanged(string propertyName)
{
var h = PropertyChanged;
if (h != null)
h(this, new PropertyChangedEventArgs(propertyName));
}
}
}

Command.cs

using System;
using System.Windows.Input;

namespace SampleWpf
{
internal class Command : ICommand
{
private readonly Action<object> _execute;

public Command(Action<object> execute)
{
_execute = execute;
}

public bool CanExecute(object parameter) { return true; }
public event EventHandler CanExecuteChanged;
public void Execute(object parameter) { _execute(parameter); }
}
}

MainWindow.xaml

Inapoi