WPF C# MVVM Community Toolkit Relay Commands in own folder-CodePudding

I amd trying implement Relay Commands using Microsoft MVVM Community Toolkit. If I place the command code in the ViewModel it works. If I try to put the Command code in its own folder the command code cannot be found. I have created a very simple example below soowing the command code in the ViewModel (commented out) and my attempt to place the command ccode in its own folder. I suspect my implementation of the code in the folder is all wrong. I have found no examples of the command code in its own folder using Relay commands. I can place command code in its own folder just using ICommand & a CommandBase.

App.xaml.cs

using RelayCommandLocation.Views;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;

namespace RelayCommandLocation
{
   /// <summary>
   /// Interaction logic for App.xaml
   /// </summary>
   public partial class App : Application
   {
      protected override void OnStartup(StartupEventArgs e)
      {
         base.OnStartup(e);
         RelayCommandView relayCommandView = new RelayCommandView();
         relayCommandView.DataContext = new RelayCommandViewModel();
         relayCommandView.Show();
      }
   }
   
}

ViewModel in Folder ViewModels

using Microsoft.Toolkit.Mvvm.Input;
using RelayCommandLocation.Commands;
using System.Windows.Input;

namespace RelayCommandLocation.ViewModels
{
   public class RelayCommandViewModel : ObservableObject
   {
      public ICommand PushMeClick { get; set; }

      // ################################################################################
      // ############# This fails to compile = cannot find PushMeCommand code


      public RelayCommandViewModel()
      {
         PushMeClick = new RelayCommand(PushMeCommandX.PushMeCommand);
      }


      // ********************************************************************************
      // *********** This works. The RelayCommand code is in the ViewModel. *************

      //public RelayCommandViewModel()
      //{
      //   PushMeClick = new RelayCommand(PushMeCommand);
      //}

      //private void PushMeCommand()
      //{
      //   MessageBox.Show($"Button pushed");
      //}
   }
}

Command Code in folder Commands

using System;
using System.Windows;
using System.Windows.Input;

namespace RelayCommandLocation.Commands
{
   public class PushMeCommandX 
   {
      public void PushMeCommand()
      {
         MessageBox.Show($"Button pushed");
      }
   }
}

XAML in folder Views

        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:RelayCommandLocation.Views"
        mc:Ignorable="d"
        Title="RelayCommandView" Height="450" Width="800">
    <Grid>
        <Button Content="Push Me" Command="{Binding PushMeClick}" Height="50" Width="75" />
    </Grid>
</Window>

Is it possible to place the Relay Command code in its own folder?

CodePudding user response：

From the comment of @Klaus Gutter, you need to create an instance of the PushMeCommandX in your RelayCommandViewModel

using Microsoft.Toolkit.Mvvm.Input;
using RelayCommandLocation.Commands;
using System.Windows.Input;

namespace RelayCommandLocation.ViewModels
{
   public class RelayCommandViewModel : ObservableObject
   {
      public ICommand PushMeClick { get; set; }
      // Create property or a field for your PushMeCommandX class.
      public PushMeCommandX PushMe {get; set;}

      public RelayCommandViewModel()
      {
         // Create an instance of the PushMeCommandX class to get access to it's methods.
         PushMe = new PushMeCommandX();
         PushMeClick = new RelayCommand(PushMe.PushMeCommand);
      }
    }
}

I will side with @Sir Rufo to read some Tutorial about C# classes.