如何创建数量可变的RichTextBoxOverflow元素

Question

我正在千方百计地尝试跳出必须基于任意输入文本长度创建多个RichTextBlockOverflow控件的循环，但没有成功。HasOverflowContent属性既不同步也不异步更新。

变量bool "ThereIsText“我不能理解何时以及如何让它成为false来停止循环。

要粘贴到段落"Run“中的文本的链接是：text to paste。

MainPage.xaml：

<Page
x:Class="Text_Viewer_Test_UWP.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:Text_Viewer_Test_UWP"
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}">
    <Grid x:Name="Menù" HorizontalAlignment="Left" Width="290" Padding="0" Margin="0,21,0,0">
        <Grid Background="White">
            <Grid.RowDefinitions>
                <RowDefinition Height="50"/>
                <RowDefinition Height="50"/>
                <RowDefinition Height="50"/>
            </Grid.RowDefinitions>
            <Button  Grid.Row="0" x:Name="btnLoadText" Click="btnLoadText_Click" Content="Display text" HorizontalAlignment="Center" VerticalAlignment="Center" Width="270" Foreground="White" Height="32"/>
            <TextBlock Grid.Row="1" x:Name="txtPage" HorizontalAlignment="Center" VerticalAlignment="Center"/>
        </Grid>
    </Grid>
    <Grid x:Name="BaseGrid" Margin="320,10,30,10" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="Black">
        <ScrollViewer x:Name="PageViewer" Background="White" VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Visible" VerticalScrollMode="Disabled" HorizontalScrollMode="Enabled">
            <StackPanel x:Name="StackViewer" VirtualizingStackPanel.VirtualizationMode="Recycling" Orientation="Horizontal"/>
        </ScrollViewer>
    </Grid>
</Grid>

​

MainPage.xaml.cs：

public sealed partial class MainPage : Page
{
    RichTextBlock TextOneRich = new RichTextBlock() { Margin = new Thickness(20) };
    List<RichTextBlockOverflow> TextList = new List<RichTextBlockOverflow>();
    bool ThereIsText = true;

    public MainPage()
    {
        this.InitializeComponent();

        StackViewer.Children.Add(TextOneRich);
        TextOneRich.Width = 400;
        TextOneRich.TextAlignment = TextAlignment.Justify;

    }

    private async void btnLoadText_Click(object sender, RoutedEventArgs e)
    {
        TextList.Clear();
        TextOneRich.Blocks.Clear();
        StackViewer.Children.Clear();
        StackViewer.Children.Add(TextOneRich);


        Paragraph paragraphText = new Paragraph();
        paragraphText.Inlines.Clear();
        paragraphText.Inlines.Add(new Run { Text = "PasteTextHere" });


        await Task.Run(async () =>
        {
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                TextOneRich.Blocks.Add(paragraphText);
            });
        }).ContinueWith(async t =>
        {
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                TextList.Add(new RichTextBlockOverflow() { Width = 400, Margin = new Thickness(20) });
                StackViewer.Children.Add(TextList[0]);
                TextOneRich.OverflowContentTarget = TextList[0];
            });
        });

        await Task.Run(async () =>
        {
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, async () =>
            {
                while (ThereIsText)
                {
                    await Task.Run(async () =>
                    {
                        await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
                        {
                            TextList.Add(new RichTextBlockOverflow() { Width = 400, Margin = new Thickness(20) });
                            StackViewer.Children.Add(TextList[TextList.Count - 1]);
                            TextList[TextList.Count - 2].OverflowContentTarget = TextList[TextList.Count - 1];
                            txtPage.Text = TextList.Count.ToString();
                        });
                    });
                }
            });
        });
    }
}