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How to enable / disable menuitem (in the context menu) for the selected treeview element

I need to use a treeview control in a WPF application. I create nested data (with type DataItem) and assign it to a treeview control. Create a hierarchical table and assign it to the TreeView control. Add context menu to treeview, Now I want to disable or enable the menu item by one property SelectedItem (it should be DataItem, I think), "IsEnabled"

How to approach this?

            <HierarchicalDataTemplate x:Key="dt" ItemsSource="{Binding Items}">
                <TextBlock x:Uid="TextBlock_2" Text="{Binding Name}">
                </TextBlock>
            </HierarchicalDataTemplate>

        <TreeView x:Name="tree_3" Height="200"
                  ItemTemplate="{StaticResource dt}"
                  >
            <TreeView.ContextMenu>
                <ContextMenu>
                    <MenuItem ItemsSource="{Binding SelectedItem}"
                        Header="doA" IsEnabled="{Binding IsEnabled, Mode=OneWay}"  />
                    <MenuItem Header="doB" IsEnabled="False"/>
                    <MenuItem Header="doC" />
                </ContextMenu>
            </TreeView.ContextMenu>
        </TreeView>

class DataItem : DependencyObject //INotifyPropertyChanged
{
    private List<DataItem> _items = new List<DataItem>();
    public List<DataItem> Items 
    {
        get
        {
            return _items;
        }
    }

    public string Name { get; set; }
    public int Category { get; set; }
    public bool IsEnabled { get; set; }
}

    private void Window_Loaded(object sender, RoutedEventArgs e)
    {
        List<DataItem> allData = new List<DataItem>();

        DataItem i1 = new DataItem() { Name = "Test1", Category = 1, IsEnabled = false };
        DataItem i2 = new DataItem() { Name = "Test2", Category = 2, IsEnabled = false };
        DataItem i3 = new DataItem() { Name = "Test3", Category = 3, IsEnabled = true };

        DataItem t1 = new DataItem() { Name = "Template 1", Category = 1, IsEnabled = true  };
        DataItem t2 = new DataItem() { Name = "Template 2", Category = 1, IsEnabled = false };

        i1.Items.Add(t1);
        i1.Items.Add(t2);

        allData.Add(i1);
        allData.Add(i2);
        allData.Add(i3);
        tree_3.ItemsSource = allData;
    }

I solved the problem in the following way.

  • create a context menu resource

    <ContextMenu x:Uid="ContextMenu_1" x:Key="TreeViewItemContextMenu"
         ItemsSource="{Binding}">
    <MenuItem x:Uid="MenuItem_1" 
          Header="Rename" 
          IsEnabled="{Binding Path=., Converter={StaticResource renameMenuConverter}}"
          Click="RenameMenu_OnClick"
          />
</ContextMenu>

  • create a style for the tree view element and use the context menu resource above

    <Style TargetType="{x:Type TreeViewItem}" x:Uid="Style_1">
<Setter x:Uid="Setter_32" Property="ContextMenu" Value="{StaticResource           TreeViewItemContextMenu}">
</Setter>
...
</Style>

  • . , , , , .

.

+5
1

WinForm TreeView .

DataItems .

DataItem i1 = new DataItem() { Name = "Test1", 
                  Category = 1, IsEnabled = false, Tag = "Test1" };

EventListener TreeView SelectedItem TreeView.

//It is only Algorithm:
if treeview1.selecedItem.Tag = "Test1" then
    //code for execution
end if


//It is only Algorithm:
variable treeNode = cast ( sender to TreeView ).SelectedItem
if treeNode.Tag = "Test1" then
    //code for execution
end if

" ", MenuItems.

. x: Name MenuItems ContextMenu. , MenuItems.

IsEnabled WPF

, , VB, #. .

:)

+1

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