Forcing a WPF tooltip to stay on the screen

Question

I have a tooltip for a Label and I want it to stay open until the user moves the mouse to a different control.

I have tried the following properties on the tooltip:<

Answer 1

I was wrestling with the WPF Tooltip only the other day. It doesn't seem to be possible to stop it from appearing and disappearing by itself, so in the end I resorted to handling the Opened event. For example, I wanted to stop it from opening unless it had some content, so I handled the Opened event and then did this:

tooltip.IsOpen = (tooltip.Content != null);

It's a hack, but it worked.

Presumably you could similarly handle the Closed event and tell it to open again, thus keeping it visible.

Answer 2

Also if you ever want to put any other control in your ToolTip, it won't be focusable since a ToolTip itself can get focus. So Like micahtan said, your best shot is a Popup.

Answer 3

ToolTipService.ShowDurationProperty.OverrideMetadata(
    typeof(DependencyObject), new FrameworkPropertyMetadata(Int32.MaxValue));

It is working for me. Copy this line into your class constructor.

Answer 4

If you want to specify that only certain elements in your Window have effectively indefinite ToolTip duration you can define a Style in your Window.Resources for those elements. Here is a Style for Button that has such a ToolTip :

<Window
    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"
    ...>
    ...
    <Window.Resources>
        <Style x:Key="ButtonToolTipIndefinate" TargetType="{x:Type Button}">
            <Setter Property="ToolTipService.ShowDuration"
                    Value="{x:Static Member=sys:Int32.MaxValue}"/>
        </Style>
        ...
    </Window.Resources>
    ...
    <Button Style="{DynamicResource ButtonToolTipIndefinate}"
            ToolTip="This should stay open"/>
    <Button ToolTip="This Should disappear after the default time.">
    ...

One can also add Style.Resources to the Style to change the appearance of the ToolTip it shows, for example:

<Style x:Key="ButtonToolTipTransparentIndefinate" TargetType="{x:Type Button}">
    <Style.Resources>
        <Style x:Key="{x:Type ToolTip}" TargetType="{x:Type ToolTip}">
            <Setter Property="Background" Value="Transparent"/>
            <Setter Property="BorderBrush" Value="Transparent"/>
            <Setter Property="HasDropShadow" Value="False"/>
        </Style>
    </Style.Resources>
    <Setter Property="ToolTipService.ShowDuration"
            Value="{x:Static Member=sys:Int32.MaxValue}"/>
</Style>

Note: When I did this I also used BasedOn in the Style so everything else defined for the version of my custom control with a normal ToolTip would be applied.