Avalonia treedatagrid使用杂记

王座视角 發表於 2025-7-29 12:04:00

这里只对最近使用到的分层树做一些记录，有复选框示例，支持父级选中状态改变子集同步变化
废话不多说，直接上源码
View布局
<div class="cnblogs_code">
<pre> <TreeDataGrid
 Height="710"
 BorderBrush="Gray"
 CanUserResizeColumns="False"
 FontSize="16"
 Source="{Binding TreeDataGridSource}">
 <TreeDataGrid.Resources>
 <DataTemplate x:Key="CheckBoxCellTemplate" x:DataType="vm:TreeDataModel">
 <CheckBox IsChecked="{Binding IsSelected, Mode=TwoWay}" />
 </DataTemplate>
 </TreeDataGrid.Resources>
 </TreeDataGrid></pre>
</div>
model对象
<div class="cnblogs_code">
<pre> public class TreeDataModel : INotifyPropertyChanged
{
 private string _name;

 public string Name
 {
 get { return _name; }
 set
 {
 _name = value;
 OnPropertyChanged(nameof(Name));
 }
 }

 private int? _age;

 public int? Age
 {
 get { return _age; }
 set
 {
 _age = value;
 OnPropertyChanged(nameof(Age));
 }
 }

 public bool _isSelected;

 public bool IsSelected
 {
 get { return _isSelected; }
 set
 {
 _isSelected = value;
 OnPropertyChanged(nameof(IsSelected));

 // 如果是分类节点，更新所有子项的状态
 if (IsCategory)
 {
 foreach (var child in Children)
 {
 child.IsSelected = value;
 }
 }
 }
 }

 private string _department;

 public string Department
 {
 get => _department;
 set
 {
 if (_department != value)
 {
 _department = value;
 OnPropertyChanged(nameof(Department));
 }
 }
 }

 private string _category;

 public bool IsCategory => !string.IsNullOrEmpty(Category);

 public bool IsExpanded { get; set; } = true;

 public string Category
 {
 get { return _category; }
 set
 {
 _category = value;
 OnPropertyChanged(nameof(Category));
 }
 }

 private ObservableCollection<TreeDataModel> _children = new ObservableCollection<TreeDataModel>();

 public ObservableCollection<TreeDataModel> Children
 {
 get { return _children; }
 set
 {
 _children = value;
 OnPropertyChanged(nameof(Children));
 }
 }

 public event PropertyChangedEventHandler? PropertyChanged;

 protected virtual void OnPropertyChanged( string? propertyName = null)
 {
 PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
 }

 protected bool SetField<T>(ref T field, T value, string? propertyName = null)
 {
 if (EqualityComparer<T>.Default.Equals(field, value)) return false;
 field = value;
 OnPropertyChanged(propertyName);
 return true;
 }
}</pre>
</div>
vm 数据刷新逻辑
<div class="cnblogs_code">
<pre> private HierarchicalTreeDataGridSource<TreeDataModel> _treeDataGridSource =
 new HierarchicalTreeDataGridSource<TreeDataModel>(new List<TreeDataModel>());

public HierarchicalTreeDataGridSource<TreeDataModel> TreeDataGridSource
{
 get { return _treeDataGridSource; }
 set
 {
 _treeDataGridSource = value;
 OnPropertyChanged(nameof(TreeDataGridSource));
 }
}

private TreeDataModel selectedItem;

public TreeDataModel SelectedItem
{
 get => selectedItem;
 set
 {
 selectedItem = value;
 OnPropertyChanged(nameof(SelectedItem));
 }
}

public async void InitTreeData()
{
 List<TreeDataModel> data = new List<TreeDataModel>();
 for (int i = 0; i < 10; i++)
 {
 int value = 10 + i;
 data.Add(new TreeDataModel()
 {
 Age = value,
 Name = $"示例{value}",
 Department = "测试部",
 });
 }

 for (int i = 0; i < 7; i++)
 {
 int value = 10 + i;
 data.Add(new TreeDataModel()
 {
 Age = value,
 Name = $"张三{value}",
 Department = "研发",
 });
 }

 for (int i = 23; i < 50; i++)
 {
 int value = 10 + i;
 data.Add(new TreeDataModel()
 {
 Age = value,
 Name = $"酒香也怕巷子深{value}",
 Department = "心如止水",
 });
 }

 //聚合形成树形数据集
 var categoryGroups = data
 .GroupBy(i =>
 {
 // 按照"-"前面的部分分类
 var dashIndex = i.Department.IndexOf('-');
 return dashIndex > 0 ? i.Department.Substring(0, dashIndex) : i.Department;
 });
 List<TreeDataModel> listData = new List<TreeDataModel>();
 foreach (var group in categoryGroups)
 {
 var category = new TreeDataModel { Category = group.Key };

 foreach (var item in group)
 {
 category.Children.Add(item);
 }

 listData.Add(category);
 }

 TreeDataGridSource =
 new HierarchicalTreeDataGridSource<TreeDataModel>(listData)
 {
 Columns =
 {
 new HierarchicalExpanderColumn<TreeDataModel>(
 new TextColumn<TreeDataModel, string>(
 "人员",
 x => x.IsCategory ? $"{x.Category}({x.Children.Count}成员)" : x.Name,
 GridLength.Auto)
 ,
 x => x.Children,
 isExpandedSelector: x => x.IsExpanded),
 new TextColumn<TreeDataModel, int?>(
 "年龄",
 x => x.Age,
 GridLength.Auto),
 new TemplateColumn<TreeDataModel>(
 "",
 "CheckBoxCellTemplate", // 使用自定义模板
 width: GridLength.Auto),
 },
 };

 TreeDataGridSource.RowSelection.SelectionChanged += (s, e) =>
 {
 if (s is TreeDataGridRowSelectionModel<TreeDataModel> selec)
 {
 if (selec.SelectedItem is TreeDataModel selectModel)
 {
 SelectedItem = selectModel;
 }
 }
 };
}</pre>
</div>
关键点，
1.数据格式绑定基本都在vm完成treedatagrid数据源集合需要绑定HierarchicalTreeDataGridSource，而不是传统的ObservableCollection
2.行选中时间SelectionChanged，控件不支持直接使用SelectionChanged，需要vm业务层订阅RowSelection来引出SelectionChanged，数据集每次变化都需要重新订阅
3.复选框：
        数据集Columns绑定时其实有CheckBoxColumn列，不过这里演示通过绑定资源键的形式 x:Key="CheckBoxCellTemplate"实现复选框
        父级状态改变影响子集，Avalonia原本的TreeDataGrid并没有对这个实现，但是自己可以通过通过对IsSelected属性变化时，验证IsCategory是否是分类节点从而更改子集选中状态
  
来源：https://www.cnblogs.com/Zjl-NanKe/p/19010544

頁: [1]

琼殿技术论坛's Archiver

Avalonia treedatagrid使用杂记