WPF TreeView ObservableCollection通知示例代码 [英] WPF TreeView ObservableCollection notifying sample code

问题描述

我正在尝试编写C#WPF应用程序，并且陷入了TreeView和ObservableCollection的困扰.

I'm trying to write a C# WPF application and I'm stuck with the TreeView and ObservableCollection.

这是我的TreeView项目.

This is my TreeView Items.

| Root
--- SubItem
------ SubItem
| Root
--- SubItem
------ SubItem
---------- SubItem

我正在从其他窗口修改此项目，我需要在不重新加载所有项目的情况下更新此树形视图.我进行了搜索，找到了ObservableCollection.但是我不明白如何使用ObservableCollection并通知更改和更新此列表. 您可以给我一些示例代码还是可以帮助我做到这一点?

I'm modifyng this items from other window and I need to update this treeview without re-loading all items. I've made my search and I found ObservableCollection. But I can't understand how to use ObservableCollection and notify changes and update this list. Can you give me some sample code or help me with doing that?

推荐答案

以下是实现

Here is a good example to Implement Simplifying the WPF TreeView by Using the ViewModel Pattern.

这只是另一个示例，

您的型号:

public interface IFolder
{
    string FullPath { get; }
    string FolderLabel { get; }
    ObservableCollection<IFolder> Folders { get; } 
}

您的ViewModel:

Your ViewModel:

class ViewModel : INotifyPropertyChanged 
{
    public ViewModel()
    {

        m_folders = new ObservableCollection<IFolder>();

        //add Root items
        Folders.Add(new Folder { FolderLabel = "Dummy1", FullPath = @"C:\dummy1" });
        Folders.Add(new Folder { FolderLabel = "Dummy2", FullPath = @"C:\dummy2" });
        Folders.Add(new Folder { FolderLabel = "Dummy3", FullPath = @"C:\dummy3" });
        Folders.Add(new Folder { FolderLabel = "Dummy4", FullPath = @"C:\dummy4" });

        //add sub items
        Folders[0].Folders.Add(new Folder { FolderLabel = "Dummy11", FullPath = @"C:\dummy11" });
        Folders[0].Folders.Add(new Folder { FolderLabel = "Dummy12", FullPath = @"C:\dummy12" });
        Folders[0].Folders.Add(new Folder { FolderLabel = "Dummy13", FullPath = @"C:\dummy13" });
        Folders[0].Folders.Add(new Folder { FolderLabel = "Dummy14", FullPath = @"C:\dummy14" });

    }

    public string TEST { get; set; }


    private ObservableCollection<IFolder> m_folders;
    public ObservableCollection<IFolder> Folders
    {
        get { return m_folders; }
        set
        {
            m_folders = value;
            NotifiyPropertyChanged("Folders");
        }
    }

    void NotifiyPropertyChanged(string property)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(property));
    }

    public event PropertyChangedEventHandler PropertyChanged;
}

在xaml中:

      <TextBlock Text="Simple root binding" Foreground="Red" Margin="10,10,0,0" />
        <TreeView ItemsSource="{Binding Folders}" Margin="10">
            <TreeView.ItemTemplate>
                <DataTemplate>
                    <TreeViewItem Header="{Binding FolderLabel}"/>
                </DataTemplate>
            </TreeView.ItemTemplate>
        </TreeView>

Full code

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