Why the Text Section not Wrap ?

I’m trying to modify the exmaple to learn from the basic of fuse, I just modify the layout inside the section for display the contents of items. And I found that the “Header” section text can not wrap as I define in the “Header” class. Can someone tell me have I make some mistake ?


    <Text ux:Class="Header" Margin="10,10,10,5" TextWrapping="Wrap" FontSize="15" TextColor="#FF932C"/>
    <Text ux:Class="Comments" Margin="5,0,0,0" TextWrapping="NoWrap" FontSize="13" />
    <Text ux:Class="NewsCounts" Margin="5,5,5,5" TextWrapping="NoWrap" FontSize="15" Alignment="Center"/>

        <StackPanel Alignment="Top" Background="#FFF">
            <Panel Height="7" />
            <Each Items="{dataSource.results.collection1}">
                <Panel ux:Class="HorizontalBar" Margin="46,10,0,10"
                    <Rectangle Height="1" Fill="#dcdee3" />
                <StackPanel Orientation="Horizontal">
                    <NewsCounts Value="{count}" />
                    <StackPanel Orientation="Vertical">
                        <Header Value="{title.text}" />
                        <StackPanel Orientation="Horizontal">
                            <Comments Value="Posted by" />
                            <Comments Value="{username.text}" />
                            <Comments Value="{points}" />
                            <Comments Value="{comments.text}" />
                <HorizontalBar />