Show WPF tooltip on disabled item only

Question

Just wondering if it is possible to show a WPF on a disabled item ONLY (and not when the item is enabled).

I would like to give the user a tooltip explaining why an item is currently disabled.

I have an IValueConverter to invert the boolean IsEnabled property binding. But it doesn't seem to work in this situation. The ToolTip is show both when the item is enabled and disabled.

So is is possible to bind a ToolTip.IsEnabled property exclusively to an item's own !IsEnabled?

Pretty straightforward question I guess, but code example here anyway:

public class BoolToOppositeBoolConverter : IValueConverter
{
    #region IValueConverter Members

    public object Convert(object value, Type targetType, object parameter,
        System.Globalization.CultureInfo culture)
    {
        if (targetType != typeof(bool))
            throw new InvalidOperationException("The target must be a boolean");

        return !(bool)value;
    }

    public object ConvertBack(object value, Type targetType, object parameter,
        System.Globalization.CultureInfo culture)
    {
        if (targetType != typeof(bool))
            throw new InvalidOperationException("The target must be a boolean");

        return !(bool)value;
    }

    #endregion
}

And the binding:

<TabItem Header="Tab 2" Name="tabItem2" ToolTip="Not enabled in this situation." ToolTipService.ShowOnDisabled="True" ToolTipService.IsEnabled="{Binding Path=IsEnabled, ElementName=tabItem2, Converter={StaticResource oppositeConverter}}">
    <Label Content="Item content goes here" />
</TabItem>

Thanks folks.

Are you sure ToolTipService.ShowOnDisabled="True" isn't executing "after" your inversion? It seems like only the enabled binding should be necessary. — JustABill, May 23 '10 at 16:03
@JustABill: That might be the case but it doesn't work without ToolTipService.ShowOnDisabled="True". Maybe I need to handle it in code-behind. I'd prefer to keep GUI stuff in XAML if possible. — dant, May 23 '10 at 23:06
In that case, I suggest you bind to Tooltip like ToolTip="{Binding ElementName=tabItem2, Path=IsEnabled, Converter={StaticResource newconverter}, ConverterParameter=Actual tooltip text goes here}", where newconverter is a new type that returns the value in parameter if the value is true. Or false in your case I guess. (Also I typed that from memory so forgive me if the syntax is off) — JustABill, May 24 '10 at 02:35

dant · Accepted Answer · 2010-06-30T03:40:55.237

JustABill's suggestion worked. I also needed to define the string as a resource to avoid problems with quotation marks. And you still need to set ToolTipService.ShowOnDisabled="True".

So, here is the working code which shows how to display a tooltip in WPF only when an item is disabled.

In the top container, include the system namespace (see sys below). I also have a Resources namespace, which I called "Res".

    <Window x:Class="MyProjectName.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:sys="clr-namespace:System;assembly=mscorlib"
    xmlns:Res="clr-namespace:MyProjectName.Resources"
    >

Then you need

<Window.Resources>
    <Res:FalseToStringConverter x:Key="falseToStringConv" />
    <sys:String x:Key="stringToShowInTooltip">This item is disabled because...</sys:String>
</Window.Resources>

In my case, it was a tab item that I was interested in. It could be any UI element though...

<TabItem Name="tabItem2" ToolTipService.ShowOnDisabled="True" ToolTip="{Binding Path=IsEnabled, ElementName=tabItem2, Converter={StaticResource falseToStringConv}, ConverterParameter={StaticResource stringToShowInTooltip}}">
            <Label Content="A label in the tab" />
</TabItem>

And the converter in code behind (or wherever you want to put it). Note, mine went into the a namespace called Resources, which was declared earlier.

public class FalseToStringConverter : IValueConverter
{
    #region IValueConverter Members

    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (value is bool && parameter is string)
        {
            if ((bool)value == false)
                return parameter.ToString();
            else return null;
        }
        else
            throw new InvalidOperationException("The value must be a boolean and parameter must be a string");
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }
    #endregion
}

score 17 · Answer 2 · answered Jul 14 '14 at 10:47

A little out of date, but I got this working by setting RelativeSource mode to Self instead of setting the ElementName within the Binding.

<TabItem Header="Tab 2" Name="tabItem2" ToolTip="Not enabled in this situation." ToolTipService.ShowOnDisabled="True" ToolTipService.IsEnabled="{Binding Path=IsEnabled, RelativeSource={RelativeSource Mode=Self}, Converter={StaticResource oppositeConverter}}">
    <Label Content="Item content goes here" />
</TabItem>

Thanks, this seems much simpler than the accepted solution! – Frederik Mar 18 '22 at 10:07 — Frederik, Mar 18 '22 at 10:07

Show WPF tooltip on disabled item only

2 Answers2