code snippets for "MVP In Silverlight/WPF: Implementing The Overview UserControl" post

s1.cs

public class GetAllUserGroupsResponse : Response
{
    public UserGroupDto[] UserGroups { get; set; }
}

s2.cs

public class UserGroupDto
{
    public Guid Id { get; set; }
    public string Name { get; set; }
    public Guid? ParentId { get; set; }
}

s3.cs

public class HierarchicalUserGroupBindingModel : BindingModel<HierarchicalUserGroupBindingModel>
{
    public HierarchicalUserGroupBindingModel()
    {
        Children = new ObservableCollection<HierarchicalUserGroupBindingModel>();
    }
 
    public Guid Id { get; set; }
 
    private string name;
 
    public string Name
    {
        get { return name; }
        set
        {
            name = value;
            NotifyPropertyChanged(m => m.Name);
        }
    }
 
    public ObservableCollection<HierarchicalUserGroupBindingModel> Children { get; private set; }
}

s4.cs

public class UserGroupsBindingModel : BindingModel<UserGroupsBindingModel>
{
    public UserGroupsBindingModel()
    {
        UserGroups = new ObservableCollection<HierarchicalUserGroupBindingModel>();
    }
 
    public ObservableCollection<HierarchicalUserGroupBindingModel> UserGroups { get; private set; }
}

s5.cs

public void PopulateFrom(IEnumerable<UserGroupDto> dtos)
{
    var dictionary = dtos.ToDictionary(dto => dto.Id, dto => new HierarchicalUserGroupBindingModel { Id = dto.Id, Name = dto.Name });
 
    foreach (var userGroup in dictionary.Values)
    {
        var parentId = dtos.First(d => d.Id == userGroup.Id).ParentId;
 
        if (parentId.HasValue)
        {
            dictionary[parentId.Value].Children.Add(userGroup);
        }
    }
 
    var rootIds = dtos.Where(d => d.ParentId == null).Select(d => d.Id);
    dictionary.Values.Where(u => rootIds.Contains(u.Id)).ToList().ForEach(u => UserGroups.Add(u));
}

s6.cs

public HierarchicalUserGroupBindingModel AddUserGroup(Guid id, string name, Guid? parentId = null)
{
    var newUserGroup = new HierarchicalUserGroupBindingModel { Id = id, Name = name };
 
    if (!parentId.HasValue)
    {
        UserGroups.Add(newUserGroup);
    }
    else
    {
        FindGroupById(parentId.Value, UserGroups).Children.Add(newUserGroup);
    }
 
    return newUserGroup;
}
 
private static HierarchicalUserGroupBindingModel FindGroupById(Guid id, IEnumerable<HierarchicalUserGroupBindingModel> usergroups)
{
    foreach (var usergroup in usergroups)
    {
        if (usergroup.Id == id) return usergroup;
        var childGroup = FindGroupById(id, usergroup.Children);
        if (childGroup != null) return childGroup;
    }
 
    return null;
}

s7.cs

public void RemoveUserGroup(Guid id)
{
    if (UserGroups.Any(u => u.Id == id))
    {
        UserGroups.Remove(UserGroups.First(u => u.Id == id));
    }
    else
    {
        var parent = FindParentOfChildWithId(id, UserGroups);
        parent.Children.Remove(parent.Children.First(u => u.Id == id));
    }
}
 
private static HierarchicalUserGroupBindingModel FindParentOfChildWithId(Guid id, IEnumerable<HierarchicalUserGroupBindingModel> usergroups)
{
    foreach (var usergroup in usergroups)
    {
        if (usergroup.Children.Any(u => u.Id == id)) return usergroup;
        var childGroup = FindParentOfChildWithId(id, usergroup.Children);
        if (childGroup != null) return childGroup;
    }
 
    return null;
}

s8.cs

public void UpdateUserGroup(Guid id, string name, Guid? parentId)
{
    var group = FindGroupById(id, UserGroups);
    group.Name = name;
 
    var parent = FindParentOfChildWithId(id, UserGroups);
 
    if (parent == null)
    {
        if (parentId.HasValue)
        {
            UserGroups.Remove(group);
            FindGroupById(parentId.Value, UserGroups).Children.Add(group);
        }
    }
    else
    {
        if (parentId.HasValue && parent.Id != parentId.Value)
        {
            parent.Children.Remove(group);
            FindGroupById(parentId.Value, UserGroups).Children.Add(group);
        }
        else if (!parentId.HasValue)
        {
            parent.Children.Remove(group);
            UserGroups.Add(group);
        }
    }
}

s9.cs

public class UserGroupsPresenter : Presenter<IUserGroupsView, UserGroupsBindingModel>
{
    public UserGroupsPresenter(IUserGroupsView view, IAsyncRequestDispatcherFactory requestDispatcherFactory, IEventAggregator eventAggregator)
        : base(view, eventAggregator, requestDispatcherFactory) {}
}