Introduction

You're tired of create an observableCollection for UI and another list for your DB Model (SQlite, Azure Mobile Service,..) in Windows Store App , Windows Phone or WPF application that uses MVVM and when add or remove item you do the action in both lists

MVVM Collection

MVVMCollection is a collection that implements the complete MVVM pattern with a DB Model, MVVM Collection inherits ObservableCollection which notify the UI once a change happens in the Collection and uses Dependency Injection for the DB Model when adding or removing data from the Collection. To start using MVVM Collection in a project.

Create new Repository Class of your DB Model that Implements IModelRepository.
Create new MVVMCollectionFactory object with passing the created Repository type as a Generic type and the factory will auto create the Repository.
From MVVMCollectionFactory create new MVVMCollection of any class type that exist in your DB Model and bind it to any list.

Detailed code steps

Create Repository that implements IModelRepository

public class SQLiteMVVMRepository : IModelRepository { public async Task Add(T itemToAdd) where T : new() { await DBServices.SQLiteConnector.InsertAsync(itemToAdd);

 }

 public async Task Remove<T>(T itemToDelete) where T : new()
 {
     await DBServices.SQLiteConnector.DeleteAsync(itemToDelete);
 }

 public async Task<IList<T>> RetrieveAll<T>() where T : new()
 {
     return await DBServices.SQLiteConnector.Table<T>().ToListAsync();
 }

 public async Task<IList<T>> RetrievePredicate<T>(System.Linq.Expressions.Expression<Func<T, bool>> predicate) where T : new()
 {
     return await DBServices.SQLiteConnector.Table<T>().Where(predicate).ToListAsync();
 }

}

Create new MVVMCollectionFactory with injecting the repository

     MVVMCollectionFactory<SQLiteMVVMRepository> SQLiteCollectionFacotry;
     SQLiteCollectionFacotry = new MVVMCollectionFactory<SQLiteMVVMRepository>();

Create MVVMCollection for the Created MVVMCollectionFactory and bind it to any List

     CompanyMVVMCollection = SQLiteCollectionFacotry.NewMVVMCollection<Company>();
     DeveloperCompanyComboBox.ItemsSource = await CompanyMVVMCollection.LoadAllModelData();

Add or Remove any items and it will be reflected in the DB

     await CompanyMVVMCollection.Add(newCompany);
     await CompanyMVVMCollection.Remove(DeveloperCompanyComboBox.SelectedItem as Company);

MVVM Collection Settings

You have 2 settings to creating a new MVVM Collection

Add item to Model First then update the view ( Default setting )
Add to view first then update the model

and to change the settings all you have to do is passing MVVMCollectionSettings to the NewMVVMCollection function

        MVVMCollectionSettings settings = new MVVMCollectionSettings(MVVMCollectionActionSettings.UpdateViewFirst);
        CompanyMVVMCollection = SQLiteCollectionFacotry.NewMVVMCollection<Company>(settings);

Install Nuget Package

Install-Package MVVMHandler.dll

Samples

You'll find to samples

SQLite Sample with MVVMCollection
Microsoft Azure Mobile Service with MVVMCollection

Missing Features

IOC Container for registering and resolving MVVMCollections of a certain Model Type.
Handling more complex scenarios not only CRUD operations.
Any great feature that you see it needs to be implemented :)

Motivation

I think it worth your effort to make a lot of developers happier, why MVVM Collection because in every project I developed I wasted a lot of time syncing between the UI and the Model. Thats why I start to think about MVVMCollection.

Contributors

Ibraheem Osama Mohamed
MVVM Collection can't wait to see your name is written here :)

alyahmedaly/MVVMCollection