简单使用例子

代码

 <Grid>
        <Button
            x:Name="btnShowPopup"
            Width="200"
            Height="24"
            Click="BtnShowPopup_OnClick">
            Show Popup
        </Button>
        <Popup
            x:Name="pop1"
            Width="120"
            Height="120"
            AllowsTransparency="True"
            IsOpen="False"
            Placement="Bottom"
            PlacementTarget="{Binding ElementName=btnShowPopup}"
            PopupAnimation="Slide"
            StaysOpen="False">
            <StackPanel Background="Gray">
                <Button Content="button1" />
                <Button Content="button2" />
                <Button Content="button3" />
            </StackPanel>
        </Popup>
    </Grid>

        private void BtnShowPopup_OnClick(object sender, RoutedEventArgs e)
        {
            pop1.IsOpen = true;
        }

效果