Editing in WinUI TreeView
8 Jul 202611 minutes to read
The TreeView provides support for editing and it can be enabled or disabled by using the SfTreeView.AllowEditing property. You can enter edit mode in a node by pressing the F2 key only. The editing changes in a node will be committed only when the user moves to the next node or presses the Enter key.
It is necessary to define an EditTemplate or EditTemplateSelector for bound mode to enable editing. For unbound mode, a text box will be loaded in edit mode by default.
<treeView:SfTreeView x:Name="treeView"
Width="400"
Height="500"
AutoExpandMode="AllNodes"
BorderBrush="LightGray"
BorderThickness="1"
AllowEditing="True"
IsAnimationEnabled="True"
ChildPropertyName="Files"
ItemsSource="{Binding Folders}">
<treeView:SfTreeView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<ContentPresenter Width="20"
Height="20"
HorizontalAlignment="Stretch"
VerticalAlignment="Center"
ContentTemplate="{Binding ImageTemplate}" />
<TextBlock Margin="5"
VerticalAlignment="Center"
Text="{Binding FileName}" />
</StackPanel>
</DataTemplate>
</treeView:SfTreeView.ItemTemplate>
<treeView:SfTreeView.EditTemplate>
<DataTemplate>
<TextBox Text="{Binding Name}"
VerticalContentAlignment="Center"
Margin="-4,0,-4,0"
Height="{Binding ItemHeight,ElementName=treeView}" />
</DataTemplate>
</treeView:SfTreeView.EditTemplate>
</treeView:SfTreeView>treeView.AllowEditing = true;
Programmatic Editing
Begin editing
The TreeView allows you to edit a node programmatically by calling the BeginEdit method.
this.treeView.Loaded += TreeView_Loaded;
private void TreeView_Loaded(object sender, RoutedEventArgs e)
{
this.treeView.BeginEdit(this.treeView.Nodes[0]);
}NOTE
CurrentItem is set to the node when the BeginEdit is called.
End editing
You can call the EndEdit method to programmatically end editing for a specific node.
this.treeView.Loaded += TreeView_Loaded;
private void TreeView_Loaded(object sender, RoutedEventArgs e)
{
this.treeView.EndEdit(this.treeView.Nodes[0]);
}Revert the edited changes while pressing the Escape key
By default, the TreeView does not have support for rolling back the changes when pressing the ESC key while editing a TreeView node. However, it does support rolling back the changes when the underlying data object implements the IEditableObject interface.
The user can take a backup of existing data of a node in the BeginEdit method and can change the existing data to the current data in the CancelEdit method to rollback the changes.
The code snippet below explains a simple implementation of the IEditableObject interface to roll back the changes.
public class Country : INotifyPropertyChanged, IEditableObject
{
private bool isSelected;
internal string name;
private ObservableCollection<State> states;
internal Country backUpData;
private Country currentData;
public Country()
{
}
public Country(string name):base()
{
this.currentData = new Country();
this.currentData.name = name;
this.currentData.isSelected = false;
}
public ObservableCollection<State> States
{
get
{
return states;
}
set
{
states = value;
RaisedOnPropertyChanged("States");
}
}
public string Name
{
get
{
return this.currentData.name;
}
set
{
this.currentData.name = value;
RaisedOnPropertyChanged("Name");
}
}
public bool IsSelected
{
get
{
return this.currentData.isSelected;
}
set
{
this.currentData.isSelected = value;
RaisedOnPropertyChanged("IsSelected");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void RaisedOnPropertyChanged(string _PropertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(_PropertyName));
}
}
public void BeginEdit()
{
Debug.WriteLine("BeginEdit is Called.");
backUpData = new Country();
backUpData.name = this.currentData.name;
backUpData.isSelected = this.currentData.isSelected;
}
public void CancelEdit()
{
Debug.WriteLine("CancelEdit is Called.");
this.currentData = backUpData;
}
public void EndEdit()
{
Debug.WriteLine("EndEdit is Called.");
}
}NOTE
View sample in GitHub
Events
ItemBeginEdit Event
The ItemBeginEdit event occurs when the node enters edit mode. The TreeViewItemBeginEditEventArgs has the following members which provides information about the ItemBeginEdit event.
- Node : Gets the TreeViewNode which is being edited.
You can cancel the editing of certain nodes using custom logic within this event by setting TreeViewItemBeginEditEventArgs.Cancel as true.
treeView.ItemBeginEdit += TreeView_ItemBeginEdit;
private void TreeView_ItemBeginEdit(object sender, Syncfusion.UI.Xaml.TreeView.TreeViewItemBeginEditEventArgs e)
{
if ((e.Node.Content as Folder).FileName == "Documents")
e.Cancel = true;
}ItemEndEdit Event
The ItemEndEdit event occurs when the node leaves the edit mode. The TreeViewItemEndEditEventArgs has the following members which provides information about the ItemEndEdit event.
- Node : Gets the TreeViewNode which is being edited.
You can cancel the editing from being ended for certain nodes using custom logic within this event by setting TreeViewItemEndEditEventArgs.Cancel as true.
treeView.ItemEndEdit += TreeView_ItemEndEdit;
private void TreeView_ItemEndEdit(object sender, TreeViewItemEndEditEventArgs e)
{
if ((e.Node.Content as Folder).FileName == "Downloads")
e.Cancel = true;
}