WPF

public static class AppCore
{
    public static event EventHandler<PropertyChangedEventArgs> StaticPropertyChanged;

    public static UserEntity CurrentUser { get; private set; }

    private static string _FullName;
    public static string FullName
    {
        get { return _FullName; }
        set
        {
            if (_FullName != value)
            {
                _FullName = value;
                NotifyStaticPropertyChanged("FullName");
            }
        }
    }

    private static void NotifyStaticPropertyChanged(string propertyName)
    {
        if (StaticPropertyChanged != null)
            StaticPropertyChanged(null, new PropertyChangedEventArgs(propertyName));
    }

    public static bool Login(CredentialEntity credentials)
    {
        var loggedIn = false;

        LoginResponse response = _appSecurity.Login(credentials);

        if (response.Result == Result.Success)
        {
            CurrentUser = response.User;
            FullName = response.User.FullName;
            loggedIn = true;
        }

        return loggedIn;
    }
}

Kevin Marois wrote:

What's the best way to make a Chess board using WPF and MVVM?

Kevin Marois wrote:

BoardSquare square = board.Children.Cast<BoardSquare>().First(e => Grid.GetRow(e) == 0 && Grid.GetColumn(e) == 0);
square.Piece = new RookBlack();
 
square = board.Children.Cast<BoardSquare>().First(e => Grid.GetRow(e) == 0 && Grid.GetColumn(e) == 1);
square.Piece = new BishopBlack();

Kevin Marois wrote:

How do you reverse the board for the other player?

public BoardSquare()
{
    InitializeComponent();
    DataContext = this;
}

<UserControl x:Class="Chess.UI.WPF.Controls.BoardSquare"
    ...
    DataContext="{Binding RelativeSource={RelativeSource Self}}"
>

public event PropertyChangedEventHandler PropertyChanged;

protected void RaisePropertyChanged([CallerMemberName] string propertyName = null)
{
    var handler = PropertyChanged;
    if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}

public class MainViewModel : ViewModelBase
{
    private Contact selectedContact;
    private ObservableCollection<Contact> contactList;
    private ObservableCollection<Conversation> conversationList;
    
    public MainViewModel()
    {
        contactList = new ObservableCollection<Contact>(cbdc.Contacts);
        SelectedContact = contactList.FirstOrDefault();
    }
    
    public ObservableCollection<Contact> ContactList
    {
        get { return contactList; }
    }
    
    public Contact SelectedContact
    {
        get
        {
            return selectedContact;
        }
        set
        {
            if (selectedContact != value)
            {
                selectedContact = value;
                RaisePropertyChanged();
                PopulateConversationList();
            }
        }
    }
    
    public ObservableCollection<Conversation> ConversationList
    {
        get
        {
            return conversationList;
        }
        private set
        {
            if (conversationList != value)
            {
                conversationList = value;
                RaisePropertyChanged();
            }
        }
    }
    
    private void PopulateConversationList()
    {
        if (selectedContact == null)
        {
            ConversationList = null;
        }
        else
        {
            var conversations = from c in cbdc.Conversations
                                where c.ContactID == SelectedContact.Id
                                select c;
            
            ConversationList = new ObservableCollection<Conversation>(conversations);
        }
    }
}

public class MainViewModel : ViewModelBase
   {
       private Contact selectedContact;

       private ObservableCollection<Contact> contactList;
       private ObservableCollection<Conversation> conversationList;

       public MainViewModel()
       {
           ContactList = new ObservableCollection<Contact>(cbdc.Contacts);
           SelectedContact = ContactList.FirstOrDefault();
       }

       public ObservableCollection<Contact> ContactList
       {
           get
           {
               return contactList;
           }

           private set
           {
               if (contactList != value)
               {
                   contactList = value;
                   RaisePropertyChanged();
               }
           }
       }

       public ObservableCollection<Conversation> ConversationList
       {
           get
           {
               return conversationList;
           }
           private set
           {
               if (conversationList != value)
               {
                   conversationList = value;
                   RaisePropertyChanged();
               }
           }
       }

public Contact SelectedContact
       {
           get
           {
               return selectedContact;
           }

           set
           {
               if (selectedContact != value)
               {
                   selectedContact = value;
                   RaisePropertyChanged();
                   PopulateConversationList();
               }
           }
       }

       public void PopulateConversationList()
       {
           if (selectedContact == null)
           {
               ConversationList = null;
           }
           else
           {
               var conversations = from c in cbdc.Conversations
                                   where c.ContactID == SelectedContact.Id
                                   select c;
               ConversationList = new ObservableCollection<Conversation>(conversations);
           }

       }

   }

public class ViewModelBase: INotifyPropertyChanged
  {
      public ContactLinqToSQLClassesDataContext cbdc = new ContactLinqToSQLClassesDataContext();


      #region INotifyPropertyChanged

      public event PropertyChangedEventHandler PropertyChanged;
      internal void RaisePropertyChanged([CallerMemberName] string propertyName = null)
      {
          var handler = PropertyChanged;
          if (handler != null)
          {
              handler(this, new PropertyChangedEventArgs(propertyName));
          }
      }
      #endregion
  }

public class ViewModelBase: INotifyPropertyChanged
{
    public ContactLinqToSQLClassesDataContext cbdc = new ContactLinqToSQLClassesDataContext();


    #region INotifyPropertyChanged

    public event PropertyChangedEventHandler PropertyChanged;
    internal void RaisePropertyChanged([CallerMemberName] string propertyName = null)
    {
        var handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }
    #endregion
}

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
        MainViewModel cvm = new MainViewModel();
        ContactsLstBx.ItemsSource = cvm.ContactList;
        ConversationLstBx.ItemsSource = cvm.ConversationList;
    }
}

public void PopulateConversationList()
{
   if (selectedContact == null)
   {
       ConversationList = null;
   }
   else
   {
       var conversations = from c in cbdc.Conversations
                           where c.ContactID == SelectedContact.Id
                           select c;
       ConversationList.Clear();
       foreach (Conversation c in conversations)
       {
         ConversationList.Add(c);
       }
   }
}

ConversationList.Clear();

if (ConversationList == null)
{
   ConversationList = new ObservableCollection<Conversation>();
}

public void PopulateConversationList()
        {
            if (selectedContact == null)
            {
                ConversationList = null;
            }
            else
            {
                var conversations = from c in cbdc.Conversations
                                    where c.ContactID == SelectedContact.Id
                                    select c;

                if (ConversationList == null)
                {
                    ConversationList = new ObservableCollection<Conversation>();
                }
                ConversationList.Clear();

                foreach (Conversation c in conversations)
                {
                    ConversationList.Add(c);
                }


            }

public MainViewModel()
{
    ContactList = new ObservableCollection<Contact>(cbdc.Contacts);
    //Add this
    ConversationList = new ObservableCollection<Conversation>();
    //--------
    SelectedContact = ContactList.FirstOrDefault();
    PopulateConversationList();
}

public void PopulateConversationList()
{
if (selectedContact == null)
{
    //Change ConversationList = null; to this
    ConversationList.Clear();
}
else
{
    var conversations = from c in cbdc.Conversations
                        where c.ContactID == SelectedContact.Id
                        select c;

    ConversationList.Clear();

    foreach (Conversation c in conversations)
    {
        ConversationList.Add(c);
    }
}