MvvmCodeGenerator

MVVM code generator tool for .NET.

Install

Available on NuGet.

Why ?

I decided to create this tool to avoid having to always write boilerplate code for my ViewModels. This NuGet is built on top of the Rosyln .NET compiler.

The advantages of using it are :

• Reduce the amount of code in your ViewModels
• The ViewModels only contains the more important code
• Migrate from one MVVM Framework to another easily

Features

This NuGet allows you to generate your ViewModels with the Properties and Commands specified in your XML file. The code generated will depend on the Mvvm Frameworks you like.

This tool now support these MVVM Frameworks:

• MvvmLightLibs
• MvvmCross
• Mvvmicro
• FreshMvvm
• Prism.Core

Tutorial

You will find a complete tutorial here:

English version :

https://damienaicheh.github.io/nuget/xamarin/xamarin.forms/dotnet/2019/07/31/a-complete-overview-of-mvvmcodegenerator-en

French version :

https://damienaicheh.github.io/nuget/xamarin/xamarin.forms/dotnet/2019/07/31/a-complete-overview-of-mvvmcodegenerator-fr

Usage

Setup

First of all, install the NuGet package to your .NetStandard project for example. Then create a new file called MvvmCodeGenMapper.xml at the root of your library project. This file will contain the definition of your ViewModels.

Configure your generator

Now it's time to define which generator we want to use, 4 options are available:

• mvvmlightlibs
• mvvmcross
• mvvmicro
• freshmvvm
• prismcore

Choose the one you like and declare it inside your MvvmCodeGenMapper.xml like this:

<?xml version="1.0" encoding="UTF-8" ?>
<Resources>
    <Generator Value="mvvmlightlibs" />
</Resources>    

Create your ViewModels

Let's define the ViewModels inside the ViewModels tags. You can define as many ViewModels tags as needed. Here is an example:

<?xml version="1.0" encoding="UTF-8" ?>
<Resources>
    <Generator Value="mvvmlightlibs" />
    <ViewModels Namespace="MvvmCodeGenerator.Sample" DestinationFolder="ViewModel">
        <ViewModel Key="Root">
              <Property Name="IsLoading" Type="bool" Description="Gets or sets the loader property." />
        </ViewModel>
        <ViewModel Key="Dashboard"  Base="Root">
            <Property Name="Title" Type="string" Description="Gets or sets the title." />
            <Command Name="Buy" Description="Gets or sets the command to buy a boat" />
            <AsyncCommand Name="Consultation" Parameter="string" CanExecute="true" Description="Gets or sets the command to consult my orders" />
        </ViewModel> 
    </ViewModels>   
</Resources>    

As you can see above, you can specify a list of ViewModels for a specific namespace and destination folder.

This XML will generate the 2 ViewModels with their .g.cs class associated:

The RootViewModel.cs:

namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public partial class RootViewModel
    {
    }
}

The RootViewModel.interface.g.cs:

//------------------------------------------------------------------------------ 
// <auto-generated> 
// This code was generated by MvvmCodeGenerator.
// Runtime Version:4.0.30319.42000
// 
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated> 
//------------------------------------------------------------------------------
namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public interface IRootViewModel : System.ComponentModel.INotifyPropertyChanged
    {
        System.Boolean IsLoading
        {
            get;
        }
    }
}

The RootViewModel.part.g.cs:

//------------------------------------------------------------------------------ 
// <auto-generated> 
// This code was generated by MvvmCodeGenerator.
// Runtime Version:4.0.30319.42000
// 
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated> 
//------------------------------------------------------------------------------
namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public partial class RootViewModel : GalaSoft.MvvmLight.ViewModelBase, MvvmCodeGenerator.Sample.IRootViewModel
    {
        private System.Boolean isLoading;
        /// <summary>
        // Gets or sets the loader property.
        /// </summary>
        public System.Boolean IsLoading
        {
            get => this.isLoading;
            set => this.Set(ref this.isLoading, value);
        }
    }
}

The DashboardViewModel.cs where you will implement the Commands declared:

Folder destination ./MvvmCodeGenerator.Dev/ViewModel
namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public partial class DashboardViewModel
    {
    }
}

The DashboardViewModel.interface.g.cs:

//------------------------------------------------------------------------------ 
// <auto-generated> 
// This code was generated by MvvmCodeGenerator.
// Runtime Version:4.0.30319.42000
// 
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated> 
//------------------------------------------------------------------------------
namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public interface IDashboardViewModel : MvvmCodeGenerator.Sample.IRootViewModel
    {
        System.String Title
        {
            get;
        }

        System.Windows.Input.ICommand BuyCommand
        {
            get;
        }

        System.Boolean IsConsultationCommandRunning
        {
            get;
        }

        System.Windows.Input.ICommand ConsultationCommand
        {
            get;
        }
    }
}

The DashboardViewModel.part.g.cs:

//------------------------------------------------------------------------------ 
// <auto-generated> 
// This code was generated by MvvmCodeGenerator.
// Runtime Version:4.0.30319.42000
// 
// Changes to this file may cause incorrect behavior and will be lost if
// the code is regenerated.
// </auto-generated> 
//------------------------------------------------------------------------------
namespace MvvmCodeGenerator.Sample
{
    using System;
    using System.Collections.Generic;
    using System.Threading;
    using System.Threading.Tasks;
    using GalaSoft.MvvmLight.Command;

    public partial class DashboardViewModel : MvvmCodeGenerator.Sample.RootViewModel, MvvmCodeGenerator.Sample.IDashboardViewModel
    {
        private System.String title;
        private System.Boolean isConsultationCommandRunning;
        private GalaSoft.MvvmLight.Command.RelayCommand buyCommand;
        private GalaSoft.MvvmLight.Command.RelayCommand<string> consultationCommand;
        /// <summary>
        // Gets or sets the title.
        /// </summary>
        public System.String Title
        {
            get => this.title;
            set => this.Set(ref this.title, value);
        }

        /// <summary>
        // Gets or sets the value to know if the associated async command is running.
        /// </summary>
        public System.Boolean IsConsultationCommandRunning
        {
            get => this.isConsultationCommandRunning;
            set => this.Set(ref this.isConsultationCommandRunning, value);
        }

        /// <summary>
        // Gets or sets the command to buy a boat
        /// </summary>
        public System.Windows.Input.ICommand BuyCommand
        {
            get => this.buyCommand ?? (this.buyCommand = new GalaSoft.MvvmLight.Command.RelayCommand(ExecuteBuyCommand)); // You must implement the following method(s): ExecuteBuyCommand and OnExecuteBuyCommandAsyncError
        }

        /// <summary>
        // Gets or sets the command to consult my orders
        /// </summary>
        public System.Windows.Input.ICommand ConsultationCommand
        {
            get => this.consultationCommand ?? (this.consultationCommand = new GalaSoft.MvvmLight.Command.RelayCommand<string>(async (value) =>
            {
                try
                {
                    this.IsConsultationCommandRunning = true;
                    await ExecuteConsultationCommandAsync(value);
                }
                catch (System.Exception ex)
                {
                    OnExecuteConsultationCommandAsyncError(ex);
                }
                finally
                {
                    this.IsConsultationCommandRunning = false;
                }
            }

            , CanExecuteConsultationCommand)); // You must implement the following method(s): ExecuteConsultationCommandA