示例:WPF中TreeView自定义TreeNode泛型绑定对象来实现级联勾选

news/2024/9/20 12:09:19

一、目的：在绑定TreeView的功能中经常会遇到需要在树节点前增加勾选CheckBox框，勾选本节点的同时也要同步显示父节点和子节点状态

二、实现

三、环境

VS2022

四、示例

定义如下节点类

   public partial class TreeNodeBase<T> : SelectBindable<T>, ITreeNode{public TreeNodeBase(T t) : base(t){}private bool? _isChecked = false;public bool? IsChecked{get { return _isChecked; }set{_isChecked = value;RaisePropertyChanged();RefreshParentCheckState();RefreshChildrenCheckState();}}private void RefreshParentCheckState(){if (Parent == null)return;bool allChecked = Parent.Nodes.All(l => l.IsChecked == true);if (allChecked){Parent.CheckOnlyCurrent(true);Parent.RefreshParentCheckState();return;}bool allUnChecked = Parent.Nodes.All(l => l.IsChecked == false);if (allUnChecked){Parent.CheckOnlyCurrent(false);Parent.RefreshParentCheckState();return;}Parent.CheckOnlyCurrent(null);Parent.RefreshParentCheckState();}private void RefreshChildrenCheckState(){foreach (TreeNodeBase<T> item in Nodes){item.CheckOnlyCurrent(IsChecked);item.RefreshChildrenCheckState();}}private void CheckOnlyCurrent(bool? value){_isChecked = value;RaisePropertyChanged("IsChecked");}public TreeNodeBase<T> Parent { get; set; }private ObservableCollection<TreeNodeBase<T>> _nodes = new ObservableCollection<TreeNodeBase<T>>();public ObservableCollection<TreeNodeBase<T>> Nodes{get { return _nodes; }set{_nodes = value;RaisePropertyChanged();}}public void AddNode(TreeNodeBase<T> node){node.Parent = this;Nodes.Add(node);}}

其中核心方法是如下方法

分别在当前节点勾选有变化时去更新父节点和子节点的勾选状态