UWP:添加项目后显示ListView的垂直滚动条

<Page
    x:Class="UWPApp.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UWPApp"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
        <ScrollViewer VerticalScrollBarVisibility="Auto">
            <ListView x:Name="myListView">
                <!-- List items here -->
            </ListView>
        </ScrollViewer>
    </Grid>
</Page>