How to group procedures and reuse - ViewModel

Question

Hi Peter,
How to group procedures on line 4, 5 and 6 into one method and reuse it at its original place (line 4, or 5 or 6 ) and on line 26.
Thanks

1. class Pages_ViewModel : ICommand, INotifyPropertyChanged
2. {
3. public Color Tb3BackgroundColor { get; set; } = Colors.Orange;
4. public Visibility Tb1Visibility { get; set; } = Visibility.Hidden;
5. public Visibility Tb2Visibility { get; set; } = Visibility.Hidden;
6. public Visibility Tb3Visibility { get; set; } = Visibility.Hidden;
7. public bool Tb3BeginStoryBoard { get; set; } = false;
8. 9. public void Execute(object parameter)
9. {
10. switch (parameter.ToString())
11. {
12. case "General":
13. Tb1Visibility = Visibility.Visible;
14. OnPropertyChanged(nameof(Tb1Visibility));
15. break;
16. 18. case "Primary":
17. Tb2Visibility = Visibility.Visible;
18. Tb3Visibility = Visibility.Visible;
19. OnPropertyChanged(nameof(Tb2Visibility));
20. OnPropertyChanged(nameof(Tb3Visibility));
21. break;
22. 25. case "Secondary":
23. //TbCommonForeGround = new SolidColorBrush(Colors.Blue);
24. Tb3BeginStoryBoard = true;
25. OnPropertyChanged(nameof(Tb3BeginStoryBoard));
26. break;
27. 31. default:
28. break;
29. }
30. }
31. .....
32. 37. }
33. 39.

Answer 1

Hi Jenny,
try this tested code:

using System;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Input;
using System.Windows.Media;

namespace WpfApp2.general_pages
{
  class Pages_ViewModel : ICommand, INotifyPropertyChanged
  {
    public Color Tb3BackgroundColor { get; set; } = Colors.Orange;
    public Visibility Tb1Visibility { get; set; } = Visibility.Hidden;
    public Visibility Tb2Visibility { get; set; } = Visibility.Hidden;
    public Visibility Tb3Visibility { get; set; } = Visibility.Hidden;
    public bool Tb3BeginStoryBoard { get; set; } = false;

    private void SetVisibility(bool? tb1, bool? tb2, bool? tb3)
    {
      if (tb1.HasValue)
      {
        this.Tb1Visibility = (tb1.Value) ? Visibility.Visible : Visibility.Hidden;
        OnPropertyChanged(nameof(Tb1Visibility));
      }
      if (tb2.HasValue)
      {
        this.Tb2Visibility = (tb2.Value) ? Visibility.Visible : Visibility.Hidden;
        OnPropertyChanged(nameof(Tb2Visibility));
      }
      if (tb3.HasValue)
      {
        this.Tb3Visibility = (tb3.Value) ? Visibility.Visible : Visibility.Hidden;
        OnPropertyChanged(nameof(Tb3Visibility));
      }
    }

    public void Execute(object parameter)
    {
      switch (parameter.ToString())
      {
        case "General":
          SetVisibility(true, null, null);
          break;

        case "Primary":
          SetVisibility(null, true, true);
          break;

        case "Secondary":
          Tb3BeginStoryBoard = true;
          OnPropertyChanged(nameof(Tb3BeginStoryBoard));
          break;

        default:
          break;
      }
    }

    public event EventHandler CanExecuteChanged;
    public bool CanExecute(object parameter) => true;

    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged([CallerMemberName] string propName = "") =>
      PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));
  }
}