How Can I Open a WPF Popup with a Delay?

Question

I simply want to open up the WPF Popup with a delay, sort of like a ToolTip.

How can I achieve this?

And, by the way, Popup.PopupAnimation = PopupAnimation.Fade ... fades in too quickly. I want at least half a second in there.

Answer 1

You can create a style to be applied to the Popup in the following way:

<Style x:Key="TooltipPopupStyle" TargetType="Popup">
    <Style.Triggers>
        <DataTrigger Binding="{Binding PlacementTarget.IsMouseOver, RelativeSource={RelativeSource Self}}" Value="True">
            <DataTrigger.EnterActions>
                <BeginStoryboard x:Name="OpenPopupStoryBoard" >
                    <Storyboard>
                        <BooleanAnimationUsingKeyFrames Storyboard.TargetProperty="IsOpen" FillBehavior="HoldEnd">
                            <DiscreteBooleanKeyFrame KeyTime="0:0:0.25" Value="True"/>
                        </BooleanAnimationUsingKeyFrames>
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.EnterActions>
            <DataTrigger.ExitActions>
                <PauseStoryboard BeginStoryboardName="OpenPopupStoryBoard"/>
                <BeginStoryboard x:Name="ClosePopupStoryBoard">
                    <Storyboard>
                        <BooleanAnimationUsingKeyFrames Storyboard.TargetProperty="IsOpen" FillBehavior="HoldEnd">
                            <DiscreteBooleanKeyFrame KeyTime="0:0:1" Value="False"/>
                        </BooleanAnimationUsingKeyFrames>
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.ExitActions>
        </DataTrigger>

        <Trigger Property="IsMouseOver" Value="True">
            <Trigger.EnterActions>
                <PauseStoryboard BeginStoryboardName="ClosePopupStoryBoard" />
            </Trigger.EnterActions>
            <Trigger.ExitActions>
                <PauseStoryboard BeginStoryboardName="OpenPopupStoryBoard"/>
                <ResumeStoryboard BeginStoryboardName="ClosePopupStoryBoard" />
            </Trigger.ExitActions>
        </Trigger>
    </Style.Triggers>
</Style>

Then, whenever you want to use it, you would write markup similar to this (notice the binding for the PlacementTarget):

<TextBlock x:Name="TargetControl" Text="Hover over me!" />
<Popup PlacementTarget="{Binding ElementName=TargetControl}" Style="{StaticResource TooltipPopupStyle}">
    <Border BorderBrush="Red" BorderThickness="1" Background="White">
        <TextBlock Text="This is a Popup behaving somewhat like the tooltip!" Margin="10" />
    </Border>
</Popup>