How binding the ToolTip property from within the DataTemplate to the property of the parent UserControl?

Question

How binding user control dependecy property? I want ToolTip dependency property IsEnabled to bind from UserControl dependency property IsShowToolTip. I try RelativeSource, but this can't find source.

In UserControl i have:

        public bool IsShowToolTip
        {
            get { return (bool)GetValue(IsShowToolTipProperty); }
            set { SetValue(IsShowToolTipProperty, value); }
        }

        public static readonly DependencyProperty IsShowToolTipProperty =
            DependencyProperty.Register("IsShowToolTip", typeof(bool), typeof(SideMenuView), new PropertyMetadata(false));

In xaml:

EldHasp · Answer

Is there any way to make it work?

A bit of voodoo magic... :)

using System.Windows;
using System.Windows.Controls;

namespace Core2022.SO.JarosławPietras
{
    /// 
    /// Логика взаимодействия для SideMenuView.xaml
    /// 
    public partial class SideMenuView : UserControl
    {
        public SideMenuView()
        {
            InitializeComponent();
        }

        public bool IsShowToolTip
        {
            get { return (bool)GetValue(IsShowToolTipProperty); }
            set { SetValue(IsShowToolTipProperty, value); }
        }

        public static readonly DependencyProperty IsShowToolTipProperty =
            DependencyProperty.Register("IsShowToolTip", typeof(bool), typeof(SideMenuView), new PropertyMetadata(false));
    }

    public class SideMenuViewProxy : Freezable
    {
        public SideMenuView? SideMenuView
        {
            get { return (SideMenuView?)GetValue(SideMenuViewProperty); }
            set { SetValue(SideMenuViewProperty, value); }
        }

        // Using a DependencyProperty as the backing store for SideMenuView.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty SideMenuViewProperty =
            DependencyProperty.Register(nameof(SideMenuView), typeof(SideMenuView), typeof(SideMenuViewProxy), new PropertyMetadata(null));


        protected override Freezable CreateInstanceCore()
        {
            throw new System.NotImplementedException();
        }
    }
}

P.S. This is one of the solutions. In addition to using StaticResource, you can also pass values through the DataContext. But it is usually occupied by the ViewModel. You can also make a proxy not entirely for the object, but only for the necessary properties.

Second Example

using System.Windows;
using System.Windows.Controls;

namespace Core2022.SO.JarosławPietras
{
    /// 
    /// Логика взаимодействия для SideMenuView1.xaml
    /// 
    public partial class SideMenuView1 : UserControl
    {
        public SideMenuView1()
        {
            InitializeComponent();
        }
    }

    public class MyProxy : Freezable
    {
        public bool IsToolTipEnabled
        {
            get { return (bool)GetValue(IsToolTipEnabledProperty); }
            set { SetValue(IsToolTipEnabledProperty, value); }
        }

        // Using a DependencyProperty as the backing store for SideMenuView.  This enables animation, styling, binding, etc...
        public static readonly DependencyProperty IsToolTipEnabledProperty =
            DependencyProperty.Register(nameof(IsToolTipEnabled), typeof(bool), typeof(MyProxy), new PropertyMetadata(true));


        protected override Freezable CreateInstanceCore()
        {
            throw new System.NotImplementedException();
        }
    }

}

Full Example

Unfortunately, this method doesn't work in my example. Cannot see anything outside of the binding ItemSource.

Unfortunately, it is not possible to infer from your code what is causing your problem.

Here is a complete example demonstrating that everything works correctly.

using System.Windows;
using System.Windows.Controls;

namespace Core2022.SO.JarosławPietras
{
    public partial class SideMenuViewFull : UserControl
    {
        public SideMenuViewFull()
        {
            InitializeComponent();
        }

        public bool IsShowToolTip
        {
            get { return (bool)GetValue(IsShowToolTipProperty); }
            set { SetValue(IsShowToolTipProperty, value); }
        }

        public static readonly DependencyProperty IsShowToolTipProperty =
            DependencyProperty.Register("IsShowToolTip", typeof(bool), typeof(SideMenuViewFull), new PropertyMetadata(false));
    }

    public class SideMenuViewModel
    {
        public string[] Items { get; set; } =
        {
            "first",
            "second" ,
            "third" ,
            "fourth" ,
            "fifth" ,
            "sixth" ,
            "seventh" ,
            "eighth" ,
            "ninth" ,
            "tenth" ,
            "eleventh" ,
            "twelfth"
        };
    }
}

XAML Window:

Clicking the CheckBox in the Window changes the ToolTip.IsEnabled to the DataTemplate. Therefore, the button in the ToolTip is disabled.

mm8 · Answer

You could simply bind the ToolTipService.IsEnabled attached property of the RadioButton to your dependency property like this:

How binding the ToolTip property from within the DataTemplate to the property of the parent UserControl?

2 Answers