wp7模拟器边框没有显示一侧

Question

我在wp7应用程序中尝试设置边框，但是在模拟器边框中没有显示一条边线，我通过webclient从页面侵入时绑定来自xml的数据 这是我的代码

<Border  BorderBrush="#e4f6f8" BorderThickness="2" >
        <ScrollViewer VerticalScrollBarVisibility="Auto" >
            <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <!--TitlePanel contains the name of the application and page title-->
        <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="0,17,0,28">
            <TextBlock x:Name="contet" Text="contet" Style="{StaticResource PhoneTextNormalStyle}" FontWeight="Bold" FontSize="26" />

        </StackPanel>

        <!--ContentPanel - place additional content here-->
        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0"></Grid>
        <ListBox Height="664" ItemsSource="{Binding}" HorizontalAlignment="Left" Margin="15,52,0,6" Name="listBoxhalltickets"    Width="auto" SelectionChanged="listBoxhalltickets_SelectionChanged">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">

                        <StackPanel Width="auto">

                            <TextBlock Text="{Binding date}" FontWeight="Bold" FontSize="20" Width="auto"  />
                            <TextBlock Text="{Binding uname}" FontWeight="Bold" TextWrapping="Wrap" Width="auto" />
                            <TextBlock Text="{Binding title}" TextWrapping="Wrap" Width="auto" />

                         <!--   <TextBlock Text="..............................................................................................................................................................................." Width="auto"/>-->
                        </StackPanel>
                    </StackPanel>
                </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>


    </Grid>
        </ScrollViewer>
    </Border>

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