Question

我有这样的问题。我有一个treeview，treeviewitems是在应用程序运行时由我的代码创建的。当我单击treeviewitem时，我想创建一个事件。我该怎么办？这是我的代码

            TreeViewItem tvitem = new TreeViewItem();
            tvitem.Header = namhoc;
            tvSoDoNamHoc.Items.Add(tvitem);
            List<Khoi> dskhoi = TruyCapDuLieu.Instance.getTableKhoi().ToList();
            foreach (Khoi k in dskhoi)
            {
                TreeViewItem tvitems = new TreeViewItem();
                tvitems.Header = k.TenK;
                tvitem.Items.Add(tvitems);
                List<Lop> dslop = TruyCapDuLieu.Instance.getLopForAutoInsertLop(Member.Instance.SetNamHoc, k).ToList();
                if (dslop.Count != 0)
                {
                    foreach (Lop l in dslop)
                    {
                        TreeViewItem tvitems2 = new TreeViewItem();
                        tvitems2.Header = l.TenL;
                        tvitems.Items.Add(tvitems2);                        
                    }

                }
            }

Answer 1

您想要的事件是SelectedItemChanged

对于处理此问题的替代方法，以下代码在TreeView上创建双向可绑定的SelctedItem属性。您可以使用它来检测何时选择了一项（并在代码中将所选项设置在树上）。

public class perTreeViewHelper : Behavior<TreeView>
{
    public object BoundSelectedItem
    {
        get => GetValue(BoundSelectedItemProperty);
        set => SetValue(BoundSelectedItemProperty, value);
    }

    public static readonly DependencyProperty BoundSelectedItemProperty =
        DependencyProperty.Register("BoundSelectedItem",
            typeof(object),
            typeof(perTreeViewHelper),
            new FrameworkPropertyMetadata(null,
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault,
                OnBoundSelectedItemChanged));

    private static void OnBoundSelectedItemChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
    {
        if (args.NewValue is perTreeViewItemViewModelBase item)
            item.IsSelected = true;
    }

    protected override void OnAttached()
    {
        base.OnAttached();
        AssociatedObject.SelectedItemChanged += OnTreeViewSelectedItemChanged;
    }

    protected override void OnDetaching()
    {
        AssociatedObject.SelectedItemChanged -= OnTreeViewSelectedItemChanged;
        base.OnDetaching();
    }

    private void OnTreeViewSelectedItemChanged(object obj, RoutedPropertyChangedEventArgs<object> args)
    {
        BoundSelectedItem = args.NewValue;
    }
}

有关我最近的blog post的更多详细信息。

在C＃WPF中创建自定义事件

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