在PagedCollectionview和Silverlight中进行自定义排序

Question

您能帮我使用映射到observablecollection的PagedCollectionview在Silverlight中自定义排序吗？下面是适合排序部分的代码，但它不会刷新网格，因为未清除第一列的排序

例如。 如果我使用“描述”对它进行排序，则它可以同时在两个方向（asc和desc）工作。但是在使用“描述”对集合进行排序后，如果我单击“类型”标题，则应清除较早的排序并使用“类型”进行排序“仅列。

   private void SortCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        if (e.Action == NotifyCollectionChangedAction.Remove || e.Action == NotifyCollectionChangedAction.Reset)
            return;
        if (e.Action == NotifyCollectionChangedAction.Replace || e.Action == NotifyCollectionChangedAction.Add)
        {
            MyPVC.SortDescriptions.Clear();
            if (e.NewItems.Count > 0)
            {
                MyPVC.SortDescriptions.Clear();
                SortDescription sd = (SortDescription) e.NewItems[0];
                if (sd.PropertyName == "description")
                {
                    e.NewItems.Clear();
                    using (MyPVC.DeferRefresh())
                    {
                        ObservableCollection<MyClass> source = ((ObservableCollection<MyClass>)MyPVC.SourceCollection);
                        if (source == null)
                            return;
                        bool asc = (sd.Direction == ListSortDirection.Ascending);
                        var source1 = new List<MyClass>(source);
                        source1.Sort((a, b) =>
                        {
                            int left = 0;
                            int right = 0;
                            var ret = 0;
                            if (int.TryParse(a.description, out left) && int.TryParse(b.description, out right))
                            {
                                ret = (left < right) ? -1 : (left == right) ? 0 : 1;
                                if (!asc)
                                    ret = -ret;
                            }

                            return ret;
                        });

                        var newsource = new ObservableCollection<MyClass>(source1);
                        MyPVC = new PagedCollectionView(newsource);
                        ((INotifyCollectionChanged)MyPVC.SortDescriptions).CollectionChanged += SortCollectionChanged;
                        MyPVC.SortDescriptions.Clear();
                    }
                    MyClassDataGrid.ItemsSource = MyPVC;
                    MyPVC.Refresh();

                }
                if (sd.PropertyName == "Type")
                {
                    MyPVC.SortDescriptions.Clear();
                    //MyPVC = new PagedCollectionView(MyPVC);
                    e.NewItems.Clear();
                    using (MyPVC.DeferRefresh())
                    {
                        ObservableCollection<MyClass> source = ((ObservableCollection<MyClass>)MyPVC.SourceCollection);
                        if (source == null)
                            return;
                        bool asc = (sd.Direction == ListSortDirection.Ascending);
                        var source1 = new List<MyClass>(source);
                        source1.Sort((a, b) =>
                        {
                            int left = 0;
                            int right = 0;
                            var ret = 0;
                            if (int.TryParse(a.Type, out left) && int.TryParse(b.Type, out right))
                            {
                                ret = (left < right) ? -1 : (left == right) ? 0 : 1;
                                if (!asc)
                                    ret = -ret;
                            }

                            return ret;
                        });

                        var newsource = new ObservableCollection<MyClass>(source1);
                        MyPVC = new PagedCollectionView(newsource);
                        ((INotifyCollectionChanged)MyPVC.SortDescriptions).CollectionChanged += SortCollectionChanged;

                        MyPVC.SortDescriptions.Clear();
                    }
                }
            }
        }
    }
    private void MyClasstableView_ColumnHeaderClick(object sender, ColumnHeaderClickEventArgs e)
    {
        ((INotifyCollectionChanged) MyPVC.SortDescriptions).CollectionChanged += SortCollectionChanged;
    }

Answer 1

看起来您在这里做了太多的工作，无法实现简单的排序。 PagedCollectionView设计用于过滤，排序等。它将为您完成工作。 您具有基本的权利，但是不必进行源操作即可使排序工作。

Answer 2

感谢您的答复，Dane，但是集合中的所有数据都是字符串格式，我还需要根据日期对一些数据进行排序，因此我需要在其中使用转换。因此，我需要进行这些操作。更改代码时需要更新网格，我使用了begindataupdate（）-EndDataUpdate（）方法，但它给了我一个错误。我认为这是从UI得出的。

   private void SortCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        if (e.Action == NotifyCollectionChangedAction.Remove || e.Action == NotifyCollectionChangedAction.Reset)
            return;
        if (e.Action == NotifyCollectionChangedAction.Replace || e.Action == NotifyCollectionChangedAction.Add)
        {
            MyPVC.SortDescriptions.Clear();
            if (e.NewItems.Count > 0)
            {
                MyPVC.SortDescriptions.Clear();
                SortDescription sd = (SortDescription) e.NewItems[0];
                if (sd.PropertyName == "description")
                {
                    e.NewItems.Clear();
                    using (MyPVC.DeferRefresh())
                    {
                        ObservableCollection<MyClass> source = ((ObservableCollection<MyClass>)MyPVC.SourceCollection);
                        if (source == null)
                            return;
                        bool asc = (sd.Direction == ListSortDirection.Ascending);
                        var source1 = new List<MyClass>(source);
                        source1.Sort((a, b) =>
                        {
                            int left = 0;
                            int right = 0;
                            var ret = 0;
                            if (int.TryParse(a.description, out left) && int.TryParse(b.description, out right))
                            {
                                ret = (left < right) ? -1 : (left == right) ? 0 : 1;
                                if (!asc)
                                    ret = -ret;
                            }

                            return ret;
                        });

                        var newsource = new ObservableCollection<MyClass>(source1);
                        MyPVC = new PagedCollectionView(newsource);
                        //((INotifyCollectionChanged)LeasePVC.SortDescriptions).CollectionChanged += SortCollectionChanged;

                        //LeasePVC.Refresh();
                        LeasePVC.SortDescriptions.Clear();

                        this.MyClassDataGrid.BeginDataUpdate();
                        this.MyClassDataGrid.ItemsSource = MyPVC;
                        this.MyClassDataGrid.EndDataUpdate();
                    }


                }
                if (sd.PropertyName == "Type")
                {
                    MyPVC.SortDescriptions.Clear();
                    //MyPVC = new PagedCollectionView(MyPVC);
                    e.NewItems.Clear();
                    using (MyPVC.DeferRefresh())
                    {
                        ObservableCollection<MyClass> source = ((ObservableCollection<MyClass>)MyPVC.SourceCollection);
                        if (source == null)
                            return;
                        bool asc = (sd.Direction == ListSortDirection.Ascending);
                        var source1 = new List<MyClass>(source);
                        source1.Sort((a, b) =>
                        {
                            int left = 0;
                            int right = 0;
                            var ret = 0;
                            if (int.TryParse(a.Type, out left) && int.TryParse(b.Type, out right))
                            {
                                ret = (left < right) ? -1 : (left == right) ? 0 : 1;
                                if (!asc)
                                    ret = -ret;
                            }

                            return ret;
                        });

                        var newsource = new ObservableCollection<MyClass>(source1);
                        MyPVC = new PagedCollectionView(newsource);
                        //((INotifyCollectionChanged)LeasePVC.SortDescriptions).CollectionChanged += SortCollectionChanged;

                        //LeasePVC.Refresh();
                        LeasePVC.SortDescriptions.Clear();

                        this.MyClassDataGrid.BeginDataUpdate();
                        this.MyClassDataGrid.ItemsSource = MyPVC;
                        this.MyClassDataGrid.EndDataUpdate();
                    }
                }
            }
        }
    }
    private void MyClasstableView_ColumnHeaderClick(object sender, ColumnHeaderClickEventArgs e)
    {
        ((INotifyCollectionChanged) MyPVC.SortDescriptions).CollectionChanged += SortCollectionChanged;
    }