The Model View ViewModel (MVVM) is an architectural pattern used in software engineering that originated from Microsoft as a specialization of the presentation model design pattern introduced by Martin Fowler.

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When does implementing MVVM not make sense

I am a big fan of various patterns and enjoy learning new ones all the time however I think with all the evangelism around popular patterns and anti-patterns sometimes this causes blind adoption. I ...
15
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3answers
8k views

Who should control navigation in an MVVM application?

Example #1: I have a view displayed in my MVVM application (let's use Silverlight for the purposes of the discussion) and I click on a button that should take me to a new page. Example #2: That same ...
14
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5answers
2k views

Are value converters more trouble than they're worth?

I'm working on a WPF application with views that require numerous value conversions. Initially, my philosophy (inspired in part by this lively debate on XAML Disciples) was that I should make the view ...
12
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3answers
4k views

MVVM, DDD, and WPF Layered Application Project Structure Guidance

I am trying to setup my application's structure in VS and I want to "try" and future proof it to a reasonable level. This application will be a WPF re-write of an old Winform app that had followed no ...
7
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5answers
3k views

Should we bind view to a model property or ViewModel should have it's own..?

I am starting a project with following technical environment : .Net 4.0, Entity Framework 4.0, WPF with MVVM Architecture I saw lots of examples on the net, some books with this environment. In some ...
7
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3answers
1k views

MVVM Clarification

We are about to write our first WPF application and are becoming familiar with the MVVM pattern. We've built many Winform applications and have an architecture that has been very successful for us. ...
7
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2answers
486 views

How can I “get in the know”?

My company posted a job listing to get me a helper. A recruiter called me today and all he kept saying was "MVC this Entity Framework that..." - He sounded shocked when I said the project uses ...
7
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2answers
3k views

Is MVVM in WPF outdated? [closed]

I'm currently trying to get my head round MVVM for WPF - I don't mean get my head round the concept, but around the actual nuts and bolts of doing anything that is further off the beaten track than ...
7
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3answers
4k views

What the best way to wire up Entity Framework database context (model) to ViewModel in MVVM WPF?

As in the question above: What the best way to wire up Entity Framework database model (context) to viewModel in MVVM (WPF)? I am learning MVVM pattern in WPF, alot of examples shows how to implement ...
7
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4answers
3k views

How to make creating viewmodels at runtime less painful

I apologize for the long question, it reads a bit as a rant, but I promise it's not! I've summarized my question(s) below In the MVC world, things are straightforward. The Model has state, the View ...
6
votes
4answers
571 views

Clean, Modular Code vs MV* Frameworks [closed]

I've been hearing a-lot about the "new" MV* frameworks. I've tinkered with KnockoutJS, creating an invoicing application, but I much prefer to write clean, modular code in raw JavaScript - leveraging ...
6
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3answers
573 views

What are the rules for coupling a ViewModel and a View in the MVVM pattern?

So given the Separation of Concerns, how coupled should the View and ViewModel be? For example, I want the visibility of a Control in the View to be databound (databinded?) to a flag in the ...
6
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2answers
362 views

Given the presentation model pattern, is the view, presentation model, or model responsible for adding child views to an existing view at runtime?

I am building a Flex 4 based application using the presentation model design pattern. This application will have several different components to it as shown in the image below. The MainView and ...
5
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3answers
4k views

MVVM or MVC? Want to use the same set of classes for WPF and ASP.NET

I am a newbie in terms of Design Patterns. I just started learning MVC when I am hearing a new buzz, MVVM. I want to learn the insights of both of these by redesigning an old inventory and invoicing ...
5
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3answers
1k views

MVVM - child windows and data contexts

Should a child window have it's own data context (View-Model) or use the data context of the parent? More broadly, should each View have its own View-Model? Are there are any rules to guide making ...
5
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1answer
673 views

Are all View Models supposed to be accessed through the Main View Model in MVVM?

I am currently working on a WP8 application. My current design is to have each view bind against a specific view model directly. Looking through the samples though, it seems that another way is to ...
5
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1answer
301 views

wizard-like data collection implementation help (next, next, finish)

I'm beginning to build an interface for our field techs to close out work orders and we have many different required paper forms for different customers. I had hoped to build a system where i can set ...
4
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4answers
4k views

Who is using the MVVM architecture for large applications? [closed]

I am currently working on an LOB application which I am basing on the MVVM architecture. Going by the answers to the questions I'm asking, it seems like there are not that many people building large ...
4
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3answers
1k views

What are the pros and cons of the MVVM architecture?

In class today we were introduced to the MVVM architecture for Silverlight/WinPhone/WPF; it looks nice for big projects, but what are your thoughts on MVVM? What are the pros and cons? I want to get ...
4
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3answers
2k views

Lists & Collections in MVVM - which approach to take?

I'm currently working on a Silverlight app using Caliburn.Micro. At present, we have Views (eg: PeopleView) and View Models (eg: PeopleViewModel) that equate to 'pages' of the application. ...
4
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4answers
381 views

What determines when an application requires mvvm?

I'm developing mobile applications for Windows Phone 7. This application calls some web services and occasionally sends responses out via web services. I recently started looking into MVVM and noticed ...
4
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3answers
1k views

How to use a MessageBox using the MVVM pattern?

I am implementing a UI application using the MVVM design-pattern. The thing is, sometimes when you detect that something is wrong with data that was inputted by the user, you'd like to notify him ...
4
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2answers
5k views

What are the best practices for exception handling in n-tier applications?

What are the best practices for exception handling in n-tier applications? The application is a fat client based on MVVM pattern with .NET framework.
4
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1answer
851 views

Value of MVVM in a Line of Business Application (and a Rant of Current Development Practices)

After 2 years, I'm still struggling with MVVM as a practical method of producing working software. In some cases it's great. I did a multithreaded application that controlled a small assembly line ...
4
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1answer
3k views

WPF, MVVM, EF, POCO guidance required on simple architecture

(sorry for my poor english) I am developing a application using WPF, EF Code First using MVVM (Caliburn.Micro). It should be used mostly to CRUD work. I created a BaseViewModel<T> class from ...
4
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1answer
958 views

Which notification pattern is preferable?

I'm working on a view model for a view that presents a dialog with export options. The user selects options then clicks Export. When the view model completes the Export, the calling view model ...
4
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2answers
415 views

WCF service as a proxy for publishing real-time data to a WPF/MVVM clients

I've been tasked with creating a dashboard application to show real time updates for our servers. The raw data comes in from an XML file on our intranet which I need to parse and present to the user. ...
4
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2answers
970 views

MVVM Reporting App Approach ? Data Access Layer?

I'm trying to follow the MVVM pattern in a reporting / statistics application that I'm making in C# / WPF. I have made many model classes to hold properties as a starting point. Some of these models ...
4
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1answer
3k views

Trying to learn how to use WCF services in a WPF app, using MVVM

We're working on a major re-write of a legacy VB6 app, into a WPF app. I've written several WCF services, which are meant to be used with the new WPF app. We want to use the MVVM design pattern to ...
4
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1answer
940 views

Is ViewModel with more than one repository bad?

I'm working on a project with MVVM. Some ViewModels have more than one repository. Is ViewModels with more than one repository bad? Please provide with why it's good/bad.
4
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1answer
168 views

Contract / Project / Line-Item hierarchy design considerations

We currently have an application that allows users to create a Contract. A contract can have 1 or more Project. A project can have 0 or more sub-projects (which can have their own sub-projects, and so ...
4
votes
2answers
2k views

Hierarchical View/ViewModel/Presenters in MVPVM

I've been working with MVVM for a while, but I've recently started using MVPVM and I want to know how to create hierarchial View/ViewModel/Presenter app using this pattern. In MVVM I would typically ...
4
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1answer
467 views

When should the presentation model design pattern include one or more controllers?

I have been researching the usage of the Presentation Model design pattern for an application I am preparing to build. The specific technology I will be using is Flex though I doubt that it matters ...
4
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0answers
144 views

Loose Coupling Presenter to View in MVP

We work in a Java shop here and our web application uses an implementation of the MVP architectural pattern. Our manager comes from a .NET world, where he has been exposed to the MVVM design pattern. ...
4
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1answer
471 views

Should MVVM ViewModel inject an HTML template for default view?

I'm working on web application design that includes Knockout.js and have an overall MVVM question: Does it make sense for the ViewModel to automatically inject a default HTML template (pulled from ...
4
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1answer
474 views

Examples of different architecture methodologies

Is there a resource or site which illustrates building the same application (desktop or web) using several different contrasting architectures? Such as MVP versus MVVM versus MVC, etc. It would be ...
3
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2answers
564 views

Examples of MVVM adoption outside the Microsoft community?

IS MVVM getting any kind of traction outside the Microsoft community? Within Silverlight this is a non-issue, but for other technologies, like JavaScript it surely is: For instance Knockout.js is a ...
3
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3answers
2k views

How to organize MVVM files in solution

I'm fairly new to the MVVM concept but like a lot of the flexibility it gives me so far. However, I'm struggling to find a good way to manage my code. I have several classes that are just sitting in ...
3
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4answers
1k views

Has the MVVM pattern been adopted widely in real world Silverlight projects?

MVVM pattern is a hot word recently and I am planning to learning and refactor my existing project into this pattern. I have no experience and foresight of the potential risk. Have you guys really ...
3
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2answers
282 views

Is a 'God' ViewModel desired in WPF

My application has user controls within user controls. Please see a screen shot of one of the most beautiful applications of all time (UC = user control): All the properties live in the MainWindow ...
3
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2answers
202 views

Should Item Grouping/Filter be in the ViewModel or View layer?

I'm in a situation where I have a list of items that need to be displayed depending on their properties. What I'm unsure of is where is the best place to put the filtering/grouping logic of the ...
3
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1answer
124 views

When is it okay to reassign the model for a view in MVC?

Is it ever really acceptable to reassign the model for a view in MVC? (Or MV* where applicable.) In other words, for a single view instance, is it ever ok to reassign the view's model? That is, as ...
3
votes
1answer
344 views

Distinguishing between UI command & domain commands

I am building a WPF client application using the MVVM pattern that provides an interface on top of an existing set of business logic residing in a library which is shared with other applications. The ...
3
votes
1answer
144 views

What conventions or frameworks exist for MVVM in Perl?

We're using Catalyst to render lots of webforms in what will become a large application. I don't like the way all the form data is confusingly into a big hash in the Controller, before being passed to ...
3
votes
1answer
402 views

MVVM light Communication

I am working on a large MVVM application. I am using the MVVM light toolkit for this. The application is like a web browser with back and forward buttons. The main view is an user control. I laid the ...
3
votes
1answer
952 views

Is it common/correct using MVVM to expect multiple views and corresponding view-models for a particular model?

Consider a somewhat contrived model that goes something like: class Player { public int Health; public int Ammo; public Weapon CurrentWeapon; public PhysicalState State { ...
3
votes
3answers
251 views

Should IoC container be part of portable library?

I am seeing the benefits of Portable Class Libraries for centralizing Models and ViewModels to a single code-base. Where should dependency injection management (IoC container) take place, though? My ...
3
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0answers
236 views

What is the good way of sharing specific data between ViewModels

We have IAppContext which is injected into ViewModel. This service contains shared data: global filters and other application wide properties. But there are cases when data is very specific. For ...
2
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5answers
3k views

MVVM ViewModel and Commands

I need a bit of help to understand the relationship between a viewmodel and a command, and the responsibility of the viewmodel. I'll try to give an example (using Caliburn Micro). I have a viewmodel ...
2
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1answer
1k views

How do you do to create the ViewModel part of your MVVM designs?

Sometimes, when I plan to create a program using this architectural pattern, I've got a lot of difficulties when I'm in the View Model phase. I'm using WAF Framework to develop this architectural ...