Prism MVVM pattern with Applcaition development

Prism is one of the design patterns which defined by Microsoft Patterns and Practices team for building composite Applications in C# , XAML (WPF,Store Applications etc ) .

Why MVVM is not enough ?

When we creating application with MVVM there is few questions and practices we need to figure out. 

• Should I use Prism to provide support for MVVM?
• Should I use a dependency injection container?
  • Which dependency injection container should I use?
  • When is it appropriate to register and resolve components with a dependency injection container?
  • Should a component's lifetime be managed by the container?
• Should the app construct views or view models first?
• How should I connect view models to views?
  • Should I use XAML or code-behind to set the view's DataContext property?
  • Should I use a view model locator object?
  • Should I use an attached property to automatically connect view models to views?
  • Should I use a convention-based approach?
• Should I expose commands from my view models?
• Should I use behaviors in my views?
• Should I include design time data support in my views?
• Do I need to support a view model hierarchy?

 (reference https://msdn.microsoft.com/en-us/library/windows/apps/xx130657.aspx )

Why Prism?

Prism contains wire frame which can help to accelerate application development in  MVVM and It already contains commonly required core features in application development.

Let's Start Coding 

Here we are going to create windows store application using Prism

1. Create new windows store application project (Blank application)
2. Go to package manager console or manage nuget packages and install prism nuget to the application

 3. Now starts coding . Here we are using MVVM and I create few folders to isolate resources in the project such as

• ViewModel - for ViewModel
• Model - for Model
• Controles - for BaseControls
• View - for XAML pages 
• Enum - for enumerations
• Interfaces - for Interfaces 

and then put MainPage.xaml  in to teh View Folder (drag and drop)

Now my project like this

 Code for prism
 Now we have to convert our application to prism
1. App.XAML and App.XAML.cs

<prism:MvvmAppBase
    x:Class="SamplePrism.App"
    xmlns:prism="using:Microsoft.Practices.Prism.Mvvm"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:SamplePrism">
 
</prism:MvvmAppBase> 

sealed partial class App : MvvmAppBase
   {
       public App()
       {
           this.InitializeComponent();
       }
 
       protected override Task OnLaunchApplicationAsync(LaunchActivatedEventArgs args)
       {

          //Main is the name of view i need to navigate 
           this.NavigationService.Navigate("Main", null);
 
           return Task.FromResult<object>(null);
       }
   } 

2. Then create PageBase in controls  from Prism MVVM

public abstract partial class PageBase: Page,IView
   {
   } 

3. Then Use this page base in our Views, xaml

 Change MainPage.xaml and MainPage.xaml.cs as  follows

<controls:PageBase
    x:Class="SamplePrism.Views.MainPage"
    xmlns:prism="using:Microsoft.Practices.Prism.Mvvm"
    xmlns:controls="using:SamplePrism.Controls"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:SamplePrism.Views"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    prism:ViewModelLocator.AutoWireViewModel="True"
    xmlns:designtime="using:SamplePrism.DesignTimeViewModel"
    mc:Ignorable="d">

public sealed partial class MainPage : PageBase
    {
        public MainPage()
        {
            this.InitializeComponent();
        }
    }

4. In here I'm craeting Interface to keep the properties of MainPage But this is optional. You can jsut implement the ViewModel without this interface


Here is My interface

public interface IMainPageViewModel
   {
       string Title { get; set; }
   }

5. Lets Starts MainPageViewModel

public class MainPageViewModel : ViewModel, IMainPageViewModel
   {
       string _Title = default(string);
       public string Title { get { return _Title; } set { SetProperty(ref _Title, value); } }
 
       public override void OnNavigatedTo(object navigationParameter, NavigationMode navigationMode, Dictionary<string, object> viewModelState)
       {
           this.Title = "Hello prism";
       }
   }

With prism MVVM it conains basic funtions in store app such like OnNavigatedTo , OnNavigatedFrom etc. You can directly use them inside the ViewModel 

Run and Enjoy the Prism.

It is really easy to build in complex applications in enterprise level. even if you  not like Prism code in specific scenario you can switch with your old MVVM too inside the same project










Full Code 
http://bit.ly/1DL68OI