DataGrid—如何使列排序动态化,以满足绑定数据更改时的需要?

我正在VS2010 wpfc项目中使用DataGrid。我已将DataGrid绑定到ObservableCollection。当您单击列标题时,它会在该时间点对数据进行排序。

问题-我如何安排使DataGrid中的排序是动态的,以便当数据发生变化时(在ObservableCollection中),排序继续工作。

private ObservableCollection<SummaryItem> _summaryData = new ObservableCollection<SummaryItem>();
SummaryDataGrid.ItemsSource = _summaryData;

SummaryDataGrid.AutoGeneratingColumn += (s, e) =>
{
    //if (e.Column.Header.ToString() == "ProcessName")
    //    e.Column.Width = new DataGridLength(1, DataGridLengthUnitType.Star);
    e.Column.Width = new DataGridLength(1, DataGridLengthUnitType.Star);
};

public class SummaryItem : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private string _processName;
    public string ProcessName
    {
        get { return _processName; }
        set
        {
            _processName = value;
            NotifyPropertyChanged("ProcessName");
        }
    }

    private long _total;
    public long Total
    {
        get { return _total; }
        set
        {
            _total = value;
            NotifyPropertyChanged("Total");
        }
    }

    private long _average;
    public long Average
    {
        get { return _average; }
        set
        {
            _average = value;
            NotifyPropertyChanged("Average");
        }
    }

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

    public static SummaryItem ObservableCollectionSearch(ObservableCollection<SummaryItem> oc, string procName)
    {
        foreach (var summaryItem in oc)
        {
            if (summaryItem.ProcessName == procName) return summaryItem;
        }
        return null;
    }
}