我正在使用数据绑定和树视图，我无法在我的WPF中填充TreeView。我觉得我比较亲密，只是在某个地方稍作调整，但我似乎无法找到它。
这是我的Project类：
public class Project
{
public Project(string Name, bool isFolder, Project ParentFolder)
{
this.Name = Name;
this.isFolder = isFolder;
Children = new List<Project>();
if (ParentFolder == null)
{
Path = Name;
}
else
{
Path = ParentFolder.Path + " > " + Name;
}
}
public string Path { get; private set; }
public string Name { get; set; }
public bool isFolder { get; set; }
public List<Project> Children { get; set; }
public IEnumerable<Project> ChildFolders
{
get
{
return Children.Where(p => p.isFolder);
}
}
public object Icon
{
get
{
if (isFolder)
{
return 0; // return folder icon
}
else
{
return 1; // return project icon
}
}
}
public IEnumerable<Project> SearchRecursively(string SearchString)
{
return GetAllChildren.Where(p => p.Name.Contains(SearchString));
}
private List<Project> GetAllChildren
{
get
{
List<Project> allChildren = new List<Project>();
foreach(Project child in Children)
{
allChildren.AddRange(child.GetAllChildren);
}
return allChildren;
}
}
}
}
这是我将用于制作测试数据的MaiWindow.xaml.cs类：
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.BuildData();
}
private void BuildData()
{
List<Project> parents = new List<Project>();
Project parentOne = new Project("Apple", true, null);
Project parentTwo = new Project("Samsung", true, null);
Project parentThree = new Project("Google", true, null);
parents.Add(parentOne); parents.Add(parentTwo); parents.Add(parentThree);
Project appleMacBook = new Project("Mac", false, parentOne);
Project appleIpad = new Project("iPad", false, parentOne);
Project appleiPhone = new Project("iPhone", false, parentOne);
Project samsungGalaxy = new Project("Galaxy", false, parentTwo);
Project samsungNote = new Project("Note", false, parentTwo);
Project googlePixel = new Project("Pixel", false, parentThree);
Project googleChromecast = new Project("Chromecast", false, parentThree);
parents[0].Children.Add(appleMacBook); parents[0].Children.Add(appleIpad); parents[0].Children.Add(appleiPhone);
parents[1].Children.Add(samsungGalaxy); parents[1].Children.Add(samsungNote);
parents[2].Children.Add(googlePixel); parents[2].Children.Add(googleChromecast);
}
}
}
这是我的XAML，我试图显示TreeView。现在，它只是空白。我会很感激任何提示。
<TreeView x:Name="Hierarchy" Grid.Column="4" HorizontalAlignment="Left" Height="631" Margin="0,58,0,0" Grid.Row="1" VerticalAlignment="Top" Width="265"
ItemsSource="{Binding parents}">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding parents}" DataType="{x:Type self:Project}">
<TreeViewItem Header="{Binding Name}"></TreeViewItem>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
编辑：
这是Property类：
public string Name
{
get
{
return name;
}
set
{
name = value;
OnPropertyChanged("Name");
}
}
private string name { get; set; }
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
if(PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
XAML：
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding ChildFolders}">
<StackPanel Orientation="Horizontal" >
<Image Source="{Binding Icon}" Margin="5, 5, 5, 5"></Image>
<TextBox Text="{Binding Name, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}" BorderThickness="0" FontSize="16" Margin="5"/>
</StackPanel>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
所以，这似乎并未触发变更事件。我知道这是因为Path设置为Name +＆＃34;＆gt;＆＃34;。当我更改名称时，路径不反映更改。它只显示我以前的Name值，如果这是有意义的。
if (ParentFolder == null)
{
Path = Name;
}
else
{
Path = ParentFolder.Path + " > " + Name;
}
编辑：
public Project(string Name, bool isFolder, Project ParentFolder)
{
this.Name = Name;
this.isFolder = isFolder;
Children = new List<Project>();
this.ParentFolder = ParentFolder;
}
public string Path
{
get
{
return this.ParentFolder + " > " + this.Name;
}
set
{
this.Path = Path;
}
}
XAML：
<TextBox x:Name="FolderNameBox" Grid.Column="1" Background="White" Grid.Row="1" Grid.ColumnSpan="5"
Margin="0,0,287,654.333" VerticalContentAlignment="Center"
Padding="6" FontSize="16"
IsReadOnly="True"
Text="{Binding ElementName=Hierarchy, Path=SelectedItem.Path, UpdateSourceTrigger=PropertyChanged}">
</TextBox>
<TextBox x:Name="SearchProjectsBox" Grid.Column="5" Background="White" Grid.Row="1" Text="Search Projects"
Margin="47.333,0,0,654.333" VerticalContentAlignment="Center" Foreground="LightGray" Padding="6" FontSize="16" HorizontalAlignment="Left" Width="268" GotFocus="TextBox_GotFocus" LostFocus="TextBox_LostFocus"/>
<TreeView x:Name="Hierarchy" Grid.Column="4" HorizontalAlignment="Left" Height="631" Margin="0,58,0,0" Grid.Row="1" VerticalAlignment="Top" Width="226"
ItemsSource="{Binding Projects}">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding ChildFolders}">
<StackPanel Orientation="Horizontal" >
<Image Source="{Binding Icon}" Margin="5, 5, 5, 5"></Image>
<TextBox Text="{Binding Name, UpdateSourceTrigger=PropertyChanged}" BorderThickness="0" FontSize="16" Margin="5"/>
</StackPanel>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
<Grid Grid.ColumnSpan="2" Grid.Column="4" HorizontalAlignment="Left" Height="631" Margin="245,58,0,0" Grid.Row="1" VerticalAlignment="Top" Width="540">
<ScrollViewer HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Hidden">
<ListView Margin="0,0,10,0" Name="ProjectView" ItemsSource="{Binding Projects}" FontSize="16" Foreground="Black">
<ListView.View>
<GridView ColumnHeaderContainerStyle="{StaticResource GridHeader}">
<GridViewColumn Header="Name" Width="200" DisplayMemberBinding="{Binding ElementName=Hierarchy, Path=SelectedItem.Name, UpdateSourceTrigger=PropertyChanged}"></GridViewColumn>
<GridViewColumn Header="Directory" Width="328" DisplayMemberBinding="{Binding ElementName=Hierarchy, Path=SelectedItem.Path, UpdateSourceTrigger=PropertyChanged}"></GridViewColumn>
</GridView>
</ListView.View>
</ListView>
</ScrollViewer>
</Grid>
</Grid>
路径也会更新，但是当我看到它时，它将显示项目的路径，而不是激活的名称更改。它实时变化但不保存字符串值。只记录发生了变化。
继承我的财产变化。
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyName)
{
if(PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
答案 0 :(得分：1)
这里有一些问题。
ItemsSource="{Binding parents}"
这是parents：
private void BuildData()
{
List<Project> parents = new List<Project>();
您要求XAML检查代码隐藏类中的所有方法，查找名为parents的局部变量。这不是一个合理的要求。
如果要绑定到parents，有一些要求：必须是......
public ... get块）... 这些都不是真的。
还有两件事 - 不是必需的，但是一个非常好的主意：
ObservableCollection<T>而不是List<T>，以便它会通知UI添加或删除的项目。 INotifyPropertyChanged并在其属性值发生变化时引发PropertyChanged。同样，这是关于保持UI通知变化。 保持UI通知是绑定的全部内容：它们侦听viewmodel中的更改并更新UI。
所以你需要一个看起来像这样的主视图模型：
public class ViewModelBase : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
// C#6
/*
protected virtual void OnPropertyChanged([System.Runtime.CompilerServices.CallerMemberName] string propName = null) =>
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));
*/
protected virtual void OnPropertyChanged(string propName)
{
var handler = PropertyChanged;
if (handler != null) {
handler(this, new PropertyChangedEventArgs(propName));
}
}
}
public class MainViewModel : ViewModelBase
{
private ObservableCollection<Project> _projects;
public ObservableCollection<Project> Projects {
get { return _projects; }
set {
if (value != _projects) {
_projects = value;
OnPropertyChanged(nameof(Projects));
}
}
}
public void BuildData() {
Projects = new ObservableCollection<Project>();
// do the rest of the stuff
}
}
您应该将Project作为ProjectViewModel来自ViewModelBase的{{1}}重写，并以同样的方式提升PropertyChanged，并使用ObservableCollection<Project> Children。
在你的主窗口......
public MainWindow()
{
InitializeComponent();
var vm = new MainViewModel();
vm.BuildData();
DataContext = vm;
}
您的XAML也需要一些工作。
Projects现在有一个大写名称Children类的Project属性。 TreeViewItem Project作为其DataContext，然后使用HierarchicalDataTemplate将DataContext转换为某种视觉内容。您不使用该模板来创建TreeViewItem;您可以使用它在 TreeViewItem中创建视觉内容。 所以这是新的XAML：
<TreeView
x:Name="Hierarchy"
ItemsSource="{Binding Projects}"
Grid.Column="4"
HorizontalAlignment="Left"
Height="631"
Margin="0,58,0,0"
Grid.Row="1"
VerticalAlignment="Top"
Width="265"
>
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Children}">
<Label Content="{Binding Name}" />
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
没有理由养成DataContext = this;的习惯。一旦你开始，接下来你会知道你将在UserControl中做到这一点并在这里询问为什么在父XAML中对它的所有绑定都被破坏了。依赖属性比INPC更麻烦，你最终得到的代码应该是混合到你的MainWindow代码中的视图模型。如果你使用viewmodelsit这是世界上最简单的东西来改变你的UI。也许您希望主窗口的原始内容只是主窗口中三个标签页中的一个。保持代码正确分离使得这种事情变得更加简单。