How to swap and sort item in List at the same time?

Question

Let's say there is a list where we randomly place items:

List<string> original = new List<string>() { A,B,C,D,E,F,G,H,I,J };
Random random = new Random();
random_list = original.OrderBy(x => random.Next()).ToList();

That's not the issue. Say that after shuffling:

List<string> random_list = { E,J,A,D,H,F,C,I,G,B };

I would like to sort each random_list item randomly. So pick a random number: say 5, swap item 5 in the random_list to the "original" position, and swap it with the value that is already there. Then 5 can't be swapped anymore, because it's at the correct place. Swap then 2, then 9 etc... until the random_list is back to its original state.

I may overthink the issue. How to achieve this?

Answer 1

List<T> doesn't trigger any notifications, so the UI cannot detect when the contents of the list have changed.
I replace List<string> with ObservableCollection to update list data.
MainWindow.xaml:

  <StackPanel x:Name="sp">  
        <TabControl x:Name="txtoriginal" ItemsSource="{Binding original, Mode=TwoWay,  UpdateSourceTrigger=PropertyChanged}"/>  
        <TabControl x:Name="txtrandom_list" ItemsSource="{Binding random_list, Mode=TwoWay,  UpdateSourceTrigger=PropertyChanged}"/>  
        <TextBox x:Name="input" Background="AliceBlue" Height="40" Margin="5"/>  
        <Button x:Name="swap" Content="swap" Margin="5" Click="swap_Click" />  
    </StackPanel>  

MainWindow.xaml.cs:

using System;  
using System.Collections.ObjectModel;  
using System.ComponentModel;  
using System.Linq;  
using System.Windows;  
  
namespace SwapAndSort  
{  
  public partial class MainWindow : Window,INotifyPropertyChanged  
  {  
    public ObservableCollection<string> original { get; set; }  
    public ObservableCollection<string> random_list { get; set; }  
    public ObservableCollection<string> Random_list  
    {  
      get  
      {  
        return random_list;  
      }  
      set  
      {  
        random_list = value;  
        PropertyChanged(this, new PropertyChangedEventArgs("Random_list"));  
      }  
    }  
    public MainWindow()  
    {  
      InitializeComponent();  
      original = new ObservableCollection<string>() { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J" };  
      Random random = new Random();  
      random_list = new ObservableCollection<string>(original.OrderBy(x => random.Next()).ToList());  
      DataContext=this;  
    }  
    public event PropertyChangedEventHandler PropertyChanged;  
    private void swap_Click(object sender, RoutedEventArgs e)  
    {  
      int index = Int32.Parse( input.Text);  
      string str = original[index];  
      int index1 = random_list.IndexOf(str);  
      random_list = (ObservableCollection<string>)random_list.Swap(index, index1);  
    }  
  }  
  public static class C  
  {  
    public static ObservableCollection<T> Swap<T>(this ObservableCollection<T> list, int indexA, int indexB)  
    {  
      T tmp = list[indexA];  
      list[indexA] = list[indexB];  
      list[indexB] = tmp;  
      return list;  
    }  
  }  
}  

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