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

First off ... the credit for this answer goes to Eric Burke. He answered this very question posted in the WPF Disciples group. I thought it would be useful to put this answer out on StackOverflow too.

Basically, you need to animate the IsOpen property of the Popup with with a DiscreteBooleanKeyFrame.

Check out the following xaml (which can easily be pasted into Kaxaml or another loose xaml editing utility):

<Page
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
>
    <ContentPresenter>
        <ContentPresenter.ContentTemplate>
            <DataTemplate>
                <Grid>
                    <CheckBox
                        x:Name="cb"
                        Width="100"
                        Height="40"
                        Content="Hover Over Me"
                    />
                    <Popup
                        x:Name="popup"
                        Placement="Bottom"
                        PlacementTarget="{Binding ElementName=cb}"
                    >
                        <Border Width="400" Height="400" Background="Red"/>
                    </Popup>
                </Grid>
                <DataTemplate.Triggers>
                    <Trigger SourceName="cb" Property="IsMouseOver" Value="True">
                        <Trigger.EnterActions>
                            <BeginStoryboard x:Name="bsb">
                                <Storyboard>
                                    <BooleanAnimationUsingKeyFrames
                                        Storyboard.TargetName="popup"
                                        Storyboard.TargetProperty="IsOpen"
                                        FillBehavior="HoldEnd"
                                    >
                                        <DiscreteBooleanKeyFrame KeyTime="0:0:0.5" Value="True"/>
                                     </BooleanAnimationUsingKeyFrames>
                                </Storyboard>
                            </BeginStoryboard>
                        </Trigger.EnterActions>
                        <Trigger.ExitActions>
                            <StopStoryboard BeginStoryboardName="bsb"/>
                        </Trigger.ExitActions>
                    </Trigger>
                </DataTemplate.Triggers>
            </DataTemplate>
        </ContentPresenter.ContentTemplate>
    </ContentPresenter>
</Page>

Please note that I modified his original solution slightly ... to trigger the IsOpen on mouse over versus checking the CheckBox as he had it. All in the attempt to make Popup behave a little like ToolTip.