WPF

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);
    }
}

public class MainViewModel : ViewModelBase
{
    private Contact selectedContact;

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

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

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

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

    }

    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();
            }
        }
    }

    public void PopulateConversationList()
    {
        if (selectedContact == null)
        {
            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);
            }
        }
    }
}

<Window x:Class="ContactsList.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"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <DockPanel LastChildFill="True">
        <ListBox x:Name="ContactsLstBx" Width="200" ItemsSource="{Binding ContactList}" SelectedItem="{Binding SelectedContact, UpdateSourceTrigger=PropertyChanged}" DockPanel.Dock="Left">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Path=Name}" />
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
        <ListBox x:Name="ConversationLstBx" Width="200" ItemsSource="{Binding ConversationList}" DockPanel.Dock="Right" HorizontalAlignment="Right" >
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <TextBlock Text="{Binding Path=Title}" />
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
    </DockPanel>
</Window>

public partial class MainWindow : Window
{
    public MainViewModel ViewModel { get; private set; }

    public MainWindow()
    {
        InitializeComponent();
        ViewModel = new MainViewModel();
        DataContext = ViewModel;
    }
}

public class MainViewModel : ViewModelBase
{<br />
    //The collections can just be auto-implemented properties since we have no reason
    //to use custom logic like PropertyChanged.  Remember, the view doesn't listen for that.
    public ObservableCollection<Contact> ContactList { get; private set; }
    public ObservableCollection<Conversation> ConversationList { get; private set; }
    private Contact selectedContact;
    public Contact SelectedContact
    {
        get
        {
            return selectedContact;
        }
        set
        {
            if (selectedContact != value)
            {
                selectedContact = value; 
                PopulateConversationList();
                RaisePropertyChanged();
            }
        }
    }
    public MainViewModel()
    {
        ContactList = new ObservableCollection<Contact>(cbdc.Contacts);
        ConversationList = new ObservableCollection<Conversation>();
        SelectedContact = ContactList.FirstOrDefault();
        //Don't need the PopulateConversationList() call because it's already called
        //when setting SelectedContact
    }

    public void PopulateConversationList()
    {
        //Just optimized the if-statement a bit since Clear() is called regardless
        ConversationList.Clear();
        if (selectedContact != null)
        {
            /*
            var conversations = from c in cbdc.Conversations
                                where c.ContactID == SelectedContact.Id
                                select c;
            */
            //My simulated database call, use your call in your application
            var conversations = cbdc.GetConversations(selectedContact);

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

public class ViewModelBase : INotifyPropertyChanged
{
    protected MockDB cbdc;
    public event PropertyChangedEventHandler PropertyChanged;
    public ViewModelBase()
    {
        cbdc = new MockDB();
    }
    protected void RaisePropertyChanged([CallerMemberName] string propertyName = null) =>
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public class MockDB
{
    private Dictionary<Contact, List<Conversation>> conversations;
    public List<Contact> Contacts { get; private set; }
    public MockDB()
    {
        Contacts = CreateContacts();
        conversations = CreateConversations(Contacts);
    }
    public List<Conversation> GetConversations(Contact c) =>
        conversations[c];
    private List<Contact> CreateContacts()
    {
        return new List<Contact>()
        {
            new Contact("Jim"),
            new Contact("Bob"),
            new Contact("Mary")
        };
    }
    private Dictionary<Contact, List<Conversation>> CreateConversations(List<Contact> contacts)
    {
        Dictionary<Contact, List<Conversation>> conversationMap = new Dictionary<Contact, List<Conversation>>();
        foreach (Contact c in contacts)
            conversationMap.Add(c, CreateConversationList(c));
        return conversationMap;
    }
    private List<Conversation> CreateConversationList(Contact contact)
    {
        return new List<Conversation>()
        {
            new Conversation($"Hi {contact.Name}!"),
            new Conversation("Pleasant day today.")
        };
    }
}

public class Contact
{
    public string Name { get; private set; }

    public Contact(string contactName)
    {
        Name = contactName;
    }
}

public class Conversation
{
    public string Title { get; private set; }

    public Conversation(string conversationText)
    {
        Title = conversationText;
    }
}

Richard Deeming wrote:

You should also store the event handler delegate in a local variable before testing and calling it, since other threads might modify it between the null test and the invocation.

public event PropertyChangedEventHandler PropertyChanged;

protected void RaisePropertyChanged([CallerMemberName] string propertyName = null)
{
    PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}