UWP Get selected nodes from TreeView control

Question

How do you get the currently highlighted/selected node from a TreeView control? Based on the documentation here it should be possible to iterate through the con

Answer 1

UWP Get selected nodes from TreeView control

For Single Selection mode. TreeViewItem contains IsSelected property, you could create model class with IsSelected and bind it. After item selected IsSelected value will be changed, so you could foreach the itemsource then delete the selected item. Please refer the following steps.

Code behind

public sealed partial class MainPage : Page
{
    public MainPage()
    {
        this.InitializeComponent();
        DataSource = GetData();
    }
    private ObservableCollection<ExplorerItem> DataSource;
    private ObservableCollection<ExplorerItem> GetData()
    {
        var list = new ObservableCollection<ExplorerItem>();
        ExplorerItem folder1 = new ExplorerItem()
        {
            Name = "Work Documents",
            Type = ExplorerItem.ExplorerItemType.Folder,
            Children =
            {
                new ExplorerItem()
                {
                    Name = "Functional Specifications",
                    Type = ExplorerItem.ExplorerItemType.Folder,
                    Children =
                    {
                        new ExplorerItem()
                        {
                            Name = "TreeView spec",
                            Type = ExplorerItem.ExplorerItemType.File,
                          }
                    }
                },
                new ExplorerItem()
                {
                    Name = "Feature Schedule",
                    Type = ExplorerItem.ExplorerItemType.File,
                },
                new ExplorerItem()
                {
                    Name = "Overall Project Plan",
                    Type = ExplorerItem.ExplorerItemType.File,
                },
                new ExplorerItem()
                {
                    Name = "Feature Resources Allocation",
                    Type = ExplorerItem.ExplorerItemType.File,
                }
            }
        };
        ExplorerItem folder2 = new ExplorerItem()
        {
            Name = "Personal Folder",
            Type = ExplorerItem.ExplorerItemType.Folder,
            Children =
                    {
                        new ExplorerItem()
                        {
                            Name = "Home Remodel Folder",
                            Type = ExplorerItem.ExplorerItemType.Folder,
                            Children =
                            {
                                new ExplorerItem()
                                {
                                    Name = "Contractor Contact Info",
                                    Type = ExplorerItem.ExplorerItemType.File,
                                },
                                new ExplorerItem()
                                {
                                    Name = "Paint Color Scheme",
                                    Type = ExplorerItem.ExplorerItemType.File,
                                },
                                new ExplorerItem()
                                {
                                    Name = "Flooring Woodgrain type",
                                    Type = ExplorerItem.ExplorerItemType.File,
                                },
                                new ExplorerItem()
                                {
                                    Name = "Kitchen Cabinet Style",
                                    Type = ExplorerItem.ExplorerItemType.File,
                                }
                            }
                        }
                    }
        };

        list.Add(folder1);
        list.Add(folder2);
        return list;
    }

    private void Tree_KeyDown(object sender, KeyRoutedEventArgs e)
    {
        if (e.Key == Windows.System.VirtualKey.Delete)
        {
             DeleteSelectItem(DataSource);
        }

    }
    private ExplorerItem DeleteSelectItem(ObservableCollection<ExplorerItem> DataSource)
    {
        foreach (var item in DataSource)
        {
            if (item.IsSelected == true)
            {
                DataSource.Remove(item);
                return item;
            }

            var FindResult = DeleteSelectItem(item.Children);
            if (FindResult != null)
                return FindResult;
        }

        return null;
    }
}
public class ExplorerItem : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;
    public enum ExplorerItemType { Folder, File };
    public String Name { get; set; }
    public ExplorerItemType Type { get; set; }
    private ObservableCollection<ExplorerItem> m_children;
    public ObservableCollection<ExplorerItem> Children
    {
        get
        {
            if (m_children == null)
            {
                m_children = new ObservableCollection<ExplorerItem>();
            }
            return m_children;
        }
        set
        {
            m_children = value;
        }
    }

    private bool m_isExpanded;
    public bool IsExpanded
    {
        get { return m_isExpanded; }
        set
        {
            if (m_isExpanded != value)
            {
                m_isExpanded = value;
                NotifyPropertyChanged("IsExpanded");
            }
        }
    }

    private bool m_isSelected;
    public bool IsSelected
    {
        get { return m_isSelected; }

        set
        {
            if (m_isSelected != value)
            {
                m_isSelected = value;
                NotifyPropertyChanged("IsSelected");
            }
        }

    }

    private void NotifyPropertyChanged(String propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

class ExplorerItemTemplateSelector : DataTemplateSelector
{
    public DataTemplate FolderTemplate { get; set; }
    public DataTemplate FileTemplate { get; set; }

    protected override DataTemplate SelectTemplateCore(object item)
    {
        var explorerItem = (ExplorerItem)item;
        return explorerItem.Type == ExplorerItem.ExplorerItemType.Folder ? FolderTemplate : FileTemplate;
    }
}

Xaml

<Page.Resources>
    <DataTemplate x:Key="FolderTemplate" x:DataType="local:ExplorerItem">
        <TreeViewItem
            AutomationProperties.Name="{x:Bind Name}"
            IsExpanded="{x:Bind IsExpanded,Mode=TwoWay}"
            IsSelected="{x:Bind IsSelected,Mode=TwoWay}"
            ItemsSource="{x:Bind Children}"
            >

            <StackPanel Orientation="Horizontal">
                <Image Width="20" Source="../Assets/folder.png" />
                <TextBlock Margin="0,0,10,0" />
                <TextBlock Text="{x:Bind Name}" />
            </StackPanel>
        </TreeViewItem>
    </DataTemplate>

    <DataTemplate x:Key="FileTemplate" x:DataType="local:ExplorerItem">
        <TreeViewItem AutomationProperties.Name="{x:Bind Name}" IsSelected="{x:Bind IsSelected,Mode=TwoWay}">

            <StackPanel Orientation="Horizontal">
                <Image Width="20" Source="../Assets/file.png" />
                <TextBlock Margin="0,0,10,0" />
                <TextBlock Text="{x:Bind Name}" />
            </StackPanel>
        </TreeViewItem>
    </DataTemplate>

    <local:ExplorerItemTemplateSelector
        x:Key="ExpolrerItemTemplateSelector"
        FileTemplate="{StaticResource FileTemplate}"
        FolderTemplate="{StaticResource FolderTemplate}"
        />
</Page.Resources>
<Grid>
    <TreeView
        x:Name="TreeDataBound"
        HorizontalAlignment="Center"
        VerticalAlignment="Top"
        ItemTemplateSelector="{StaticResource ExpolrerItemTemplateSelector}"
        ItemsSource="{x:Bind DataSource,Mode=OneWay}"
        KeyDown="Tree_KeyDown"
        SelectionMode="Single"
        />
</Grid>

For the complete code sample please refer this link.