WPF 绑定集合 根据集合个数改变样式 INotifyCollectionChanged

 问题：当前ListBox Items 绑定 集合数据源ListA时候；ListA集合数据源中存在另外一个集合ListB，当更改或往ListB集合中添加数据的时候，通知改变？

实体类继承 INotifyCollectionChanged 即可实现：

BaseViewModel:

public class BaseViewModel : INotifyPropertyChanged, INotifyCollectionChanged, IDisposable
    {
        public event PropertyChangedEventHandler PropertyChanged;
        public event NotifyCollectionChangedEventHandler CollectionChanged;

        public void OnPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }

        public virtual void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
        {
            if (CollectionChanged != null)
            {
                CollectionChanged(this, e);
            }
        }

        public void Dispose()
        {
            this.OnDispose();
        }

        protected void OnDispose() { }

        public void OnCollectionChanged()
        {
        }
    }

ViewModel:

public class ViewModel : BaseViewModel
    {
        private List<Person> _lp = null;
        private RelayCommand _addCommand, _removeCommand;

        public ViewModel()
        {
            LP = new List<Person>();
            LP.Add(new Person(1, "aaa"));
            LP.Add(new Person(2, "bbb"));
        }

        public List<Person> LP
        {
            get { return _lp; }
            set { _lp = value; }
        }

        public ICommand AddCommand
        {
            get
            {
                if (_addCommand == null)
                { _addCommand = new RelayCommand(param => this.Add(), param => this.CanAdd); }
                return _addCommand;
            }
        }

        public bool CanAdd
        { get { return true; } }

        public void Add()
        {
            Person ps = new Person(3, "ccc");
            LP.Add(ps);
            CollectionChanged += new NotifyCollectionChangedEventHandler(List_CollectionChanged);
            OnPropertyChanged("LP");
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, LP[0], 0));
        }

        public ICommand RemoveCommand
        {
            get
            {
                if (_removeCommand == null)
                { _removeCommand = new RelayCommand(param => this.Remove(), param => this.CanRemove); }
                return _removeCommand;
            }
        }

        public bool CanRemove
        { get { return true; } }

        public void Remove()
        {
            LP.RemoveAt(0);
            CollectionChanged += new NotifyCollectionChangedEventHandler(List_CollectionChanged);
            OnPropertyChanged("LP");
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, LP[0], 0));
        }

        private void List_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
        {
            // ??????????
        }
    }

完美解决！！

https://social.msdn.microsoft.com/Forums/vstudio/zh-CN/1b55492b-e9ca-4610-a40d-107d64c8ea9f/inotifycollectionchanged-on-listt