I'm trying to be consistent in my Views and do all Binding in the code-behind with the IViewFor<> implementation. My bindings are all working great, except for my validation where I've implemented IDataErrorInfo on my ViewModel. Before when I just had the binding in my XAML I would include the ValidatesOnDataErrors=True (and the other needed options). Is there a way to do this in the code behind? Or maybe a better way altogether to accomplish this?
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We've been using the recommended GWT approach of building parts of our application in an MVP manner. The logic we use is based on Google's examples - the Presenter fetches/prepares data and sets it on the View, and the View contains a reference to the Presenter which it calls (e.g. in UiHandlers).
Some parts of the application which we built should be reused in other views. For example - a view which is sometimes the "main view" of a part of the application - can be used inside a pop-up in another part of the application (of course, the views/presenters are initialized differently in this other case, but basically it is the same thing).
What would be the correct approach to do stuff like this? I cannot seem to find a suitable one without resorting to ugly hacky stuff.
For example - if I put the presenter of the reused component inside the main view - it is easy to initialize the reused component, but it is ugly to receive a result back in the main presenter. This can be solved by passing a runnable or creating a custom handler or passing the parent presenter itself to the reused presenter.
All of these approaches don't seem right to me though and seem ugly.
Any ideas/experiences?
What you're describing is a view being able to be controlled by 2 distinct presenters. Abstracting those presenters behind a common API, in the form of an interface, should be enough.
You can also see it as a composite widget being used within two distinct views. The composite widget would then expose events and a public API that both views could wire to their specific presenters.
See Activites and Places,It can help you to desing and structure you app.
https://developers.google.com/web-toolkit/doc/latest/DevGuideMvpActivitiesAndPlaces
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In my application I've got about a dozen places where I need to show a country suggest box. All the code of the suggest box(including the creation of a custom SuggestOracle, it's initialization and various handlers) take up some ~100 lines of and copying it all over the project seems quite hardcore for me.
So I decided to write a custom CountrySuggestBox which extended SuggestBox wrapped in itself the construction of my custom SuggestOracle and did all the click/key handling stuff in itself. After this I was planning to just write something in the lines of #UiFiled(provided=true) CountrySuggestBox = new CountrySuggestBox(countryList); and be done with it. But for that I also need CountrySuggestBox to implement LeafValueEditor<Country> which i can't do cause SuggestBox implements HasText and these interfaces do not "like" each other.
So how can I make CountrySuggestBox an editor of country types property without writing custom editor methods in the classes using it.
Prefer composition over inheritance.
Have CountrySuggestBox extend Composite (or simply implement IsWidget) and wrap the SuggestBox.
Then you can make it a LeafValueEditor<Country> or IsEditor<LeafValueEditor<Country>> (along with TakesValue<Country> or HasValue<Country>)
Currently i am working on a project using prism where one of our modules has a viewmodel with 3000 lines of code!!!. really I would split this class to little pieces (some time is hard to read the code inside of this viewmodel)
Actually the code of the viewmodel has more less 30 properties related with commands and i think there it's good place to start.. (some idea how can i move these commands to other class?)
any ideas?
Thank you!
There are a few things you can do, firstly how much of the code should be in the view model, and how much of it should be in the model itself?
Secondly, can any of the code be part of services that the view model takes as a dependency?
Thirdly, you might want to consider a conventions based MVVM framework such as Caliburn.Micro which will allow you to use actions instead of WPF commanding, which means considerably less boilerplate code binding up verbs on your view model with events on your view, as well as other advantages.
I have a layout which works fine. This layout contains several partials, which display adverts, a side column a slideshow, etc. All of these are likely to change depending on which page (module/controller/action) of the site you are on.
What is the best way of doing this correctly? In the past I have assigned variables to my view inside my controllers, these are then passed to the partial which then displays the correct slideshow or advert. This seems ugly and not entirely correct for an MVC application.
Does anyone have any other methods of doing this?
Partials are just another view scripts.
My advice is: newer put your logic into the view scripts. Your may store the logic in:
models (remember, that you can create your own models, extending, or not extending the basic database models, eg. data hydrators)
view helpers (with parameters)
services (dependent on models, returning models)
combination of the above
Then use view helper or pass the ready data (model) to different partials.
Tip: Dependency injection is a good thing.
I have a WPF user control ...which is in MVVM. The user control(which contains a listview) need data from the page (where it is included). I have to set a property in View's code behind to get this data input. Will this comply with MVVM(But MVVM pattern do not support adding code in code behind file of view as far as i know).if not, what is the way for the same?
You want to do this via data binding. The controls are bound to properties in your viewmodel which receives the data, applies the needed logic and gives it back to the view for displaying it.
Have a look here to get an idea on how all that works.
I have got a link : http://social.msdn.microsoft.com/Forums/en/wpf/thread/a3eedc3e-0d59-420c-aba0-44fe8b00552f
But I'm not really getting whats meant by injection in it (as given below) :
an interface to the UserControl public model called IUserControlModel. It has the properties that should be visible from outside;
- a UserControlViewModel that contains a public property of type IUserControlModel that is injected in the constructor; plus all the properties used for XAML binds specific to the usercontrol implementation; XAML may have binds directly to the IUserControlModel properties too;
- a MainWindowViewModel that nests the IUserControlModel inside.
I think your problem can be solved in easier way. If you expose ItemsSource property of ListView as Dependency Property of your user control you can achieve what you want without unnecesary (in this case) overhead of implementing MVVM pattern : You then can just use databinding to add data from the page where the user control is included.
post that I think answers your question :
Post link