我有一个名为Scroller的属性，如下所示。我有一个for循环，希望能够动态更新控件的内容。
我希望这个控件的内容能够刷新每个迭代次数。 此时，TextBlock在for ...循环存在且程序终止后显示内容。
我该怎么办？
f <- function(x) {
as.list(diff(x, lag=3)/x[1:3]*100)
}
df %>%
rowwise %>%
do(data.frame(perc = f(unlist(.)))
) %>%
bind_cols(df)
# Source: local data frame [50 x 9]
# Groups: <by row>
#
# # A tibble: 50 x 9
# perc.B.var.a perc.B.var.b perc.B.var.c A.var.a A.var.b A.var.c B.var.a B.var.b B.var.c
# <dbl> <dbl> <dbl> <int> <int> <int> <int> <int> <int>
# 1 193.103448 380.00000 -56.66667 29 5 60 85 24 26
# 2 -36.708861 115.55556 -32.35294 79 45 34 50 97 23
# 3 -4.878049 -23.75000 22.44898 41 80 49 39 61 60
# 4 -71.910112 300.00000 -71.87500 89 13 96 25 52 27
# 5 -87.368421 -28.07018 10.20408 95 57 49 12 41 54
# 6 680.000000 323.80952 -12.22222 5 21 90 39 89 79
# 7 9.433962 184.61538 -81.52174 53 13 92 58 37 17
# 8 -75.555556 -61.84211 -32.78689 90 76 61 22 29 41
# 9 -19.642857 -80.00000 14.28571 56 90 42 45 18 48
# 10 -52.173913 -52.63158 480.00000 46 38 15 22 18 87
# # ... with 40 more rows
编辑：
我正在添加一个功能性解决方案来帮助演示我的问题。对不起，如果我的原始问题不够明确。
<ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Name="Scroller" Margin="0,90,0,57">
<TextBlock x:Name="Output" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" MinWidth="100" Width="{Binding ElementName=Scroller, Path=ViewportWidth}" TextWrapping="Wrap" Text="" />
</ScrollViewer>
以上是xaml文件，下面是代码。
<Window x:Class="RdElectReg.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:RdElectReg"
mc:Ignorable="d" Height="350" Width="525">
<Grid>
<Button x:Name="Start" Content="Start" HorizontalAlignment="Center" VerticalAlignment="Top" Width="75" Margin="419,56,23,0" Click="Button_Click" IsDefault="True"/>
<ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Name="Scroller" Margin="0,90,0,57">
<TextBlock x:Name="Output" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" MinWidth="100" Width="{Binding ElementName=Scroller, Path=ViewportWidth}"
TextWrapping="Wrap" Text="" />
</ScrollViewer>
</Grid>
每次调用函数ProcessFile时，它都会获取TextBlock的内容，添加一些文本并更新TextBlock。
using System.Text;
using System.Windows;
namespace RdElectReg
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
StringBuilder sb = new StringBuilder();
for (int i = 1; i <= 10000; i++)
{
sb.Append(ProcessFile(i));
}
}
private StringBuilder ProcessFile(int i)
{
StringBuilder sb1 = new StringBuilder();
string TextBlockText = Output.Text;
TextBlockText = TextBlockText + "Processing iteration " + i.ToString() + "\n";
// this property
Output.Text = TextBlockText;
for (int j = 1; j < 1000; j++) {
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Remove(sb1.Length - 1, 1);
sb1.AppendLine();
}
return sb1;
}
}
}
我的问题是在程序执行期间TextBlock不会动态更新。更新的文本仅在程序执行完后的格式中显示。
我希望TextBlock动态更新。
我希望这有助于澄清我的问题。
答案 0 :(得分：0)
Output.Content = "foobar";
这是什么意思？
编辑：请添加更多代码，以便我们真正了解您在for循环中所做的事情。
答案 1 :(得分：0)
我设法找到了Updating value of TextBlock in wpf dynamically [Sovled]发布的解决方案。
这是修改后的解决方案（XAML）：
<Window x:Class="RdElectReg.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:RdElectReg"
mc:Ignorable="d" Height="350" Width="525">
<Grid>
<Button x:Name="Start" Content="Start" HorizontalAlignment="Center" VerticalAlignment="Top" Width="75" Margin="419,56,23,0" Click="Button_Click" IsDefault="True"/>
<ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Name="Scroller" Margin="0,90,0,57">
<TextBlock x:Name="Output" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" MinWidth="100" Width="{Binding ElementName=Scroller, Path=ViewportWidth}"
TextWrapping="Wrap" Text="{Binding Textstr}" />
</ScrollViewer>
</Grid>
</Window>
代码页（斜体代码显示了实现它的其他说明）：
using System.Text;
*using System.Threading;*
using System.Windows;
namespace RdElectReg
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
*Progress viewModel = new Progress();*
public MainWindow()
{
InitializeComponent();
*this.DataContext = viewModel;*
}
private void Button_Click(object sender, RoutedEventArgs e)
{
*/// Background thread Thread to run your logic
Thread thread = new Thread(YourLogicToUpdateTextBlock);
thread.IsBackground = true;
thread.Start();*
}
*// https://stackoverflow.com/questions/38477276/updating-value-of-textblock-in-wpf-dynamically-sovled*
private void YourLogicToUpdateTextBlock()
{
StringBuilder sb = new StringBuilder();
for (int i = 1; i <= 1000; i++)
{
viewModel.Textstr = viewModel.Textstr + "Processing iteration " + i.ToString() + "\n";
sb.Append(ProcessFile(i));
}
viewModel.Textstr = viewModel.Textstr + "DONE\n";
}
private StringBuilder ProcessFile(int i)
{
StringBuilder sb1 = new StringBuilder();
for (int j = 1; j < 10000; j++) {
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Append(j.ToString() + ",");
sb1.Remove(sb1.Length - 1, 1);
sb1.AppendLine();
}
return sb1;
}
}
}
类Progress被数据绑定到文本块。课程如下：
using System.ComponentModel;
namespace RdElectReg
{
class Progress : INotifyPropertyChanged
{
private string _textstr = "";
public Progress()
{
_textstr = "";
}
public Progress(string text)
{
_textstr = text;
}
public string Textstr
{
get
{
return _textstr;
}
set
{
_textstr = value;
OnPropertyChanged("Textstr");
}
}
// property changed event
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string PropertyName)
{
if (this.PropertyChanged != null)
{
// Raise the PropertyChanged event
this.PropertyChanged(this, new PropertyChangedEventArgs(PropertyName));
}
}
}
}
我对解决方案的解释是：