Databases
StackOverflow2013
Postsdbo
POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
    primarykey
    data
    text
    <p>In our application we have many <strong>Model</strong> objects that have <strong>hundreds</strong> of properties.</p> <p>For every property on the <strong>model</strong>:</p> <pre><code>public string SubscriptionKind { get; set; } ...100x... </code></pre> <p>we had to make an INotifyPropertyChanged-enabled property on the <strong>ViewModel</strong>:</p> <pre><code>#region ViewModelProperty: SubscriptionKind private int _subscriptionKind; public int SubscriptionKind { get { return _subscriptionKind; } set { _subscriptionKind = value; OnPropertyChanged("SubscriptionKind"); } } #endregion ...100x... </code></pre> <p>which meant that when our <strong>View</strong> sent the <strong>Save</strong> event, we had to remap all these values of the view model back into the model:</p> <pre><code>customer.SubscriptionKind = this.SubscriptionKind ...100x... </code></pre> <p>This became <strong>tedious</strong> and time-consuming as the models kept changing and we had to map all changes up into the ViewModels.</p> <p>After awhile we realized that it would be more straight-forward to just <strong>connect the DataContext of the View directly</strong> to the Model which enables us to bind the XAML elements directly to the Model object properties so that the save event would simply save the object without any mapping whatsoever.</p> <p>What we <strong>lost</strong> in this move is:</p> <ul> <li><p>the ability via <code>UpdateSourceTrigger=PropertyChanged</code> to do fine-grained <strong>validation</strong> and manipulation in the ViewModel Property Setters, which I really liked: this we don't have anymore since any change in XAML simple changes the dumb property on the Model</p></li> <li><p>the ability (in the future) to create <strong>mock views</strong> which test our viewmodel's UI logic in a novel way, e.g. "if property SubscriptionKind is set to "Yearly" then (1) change discount to 10%, (2) run "congratulations animation", and (3) make order button more prominent.</p></li> </ul> <p><strong>Both</strong> of these approaches have <strong>obvious advantages</strong>, e.g. the first way "View-direct-to-Model" approach especially when combined with <strong>LINQ-to-SQL</strong> is pragmatic and enables you to produce useful software fast, and as long as you use <code>{Binding...}</code> instead of <code>x:Name</code> you still have the ability to "hand off your views to a Blend Designer".</p> <p>On the other hand, although MVVM requires you to maintain tedious mapping of Model to ViewModel, it gives you powerful <strong>validation</strong> and <strong>testing</strong> advantages that the first approach doesn't have.</p> <p><strong>How have you been able to combine the advantages of these two approaches in your projects?</strong></p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USEdward Tanguay
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COHey there - I don't have any specific advice to lend you, but when I see MVVM I have to plug my mate Kent. I don't know if any of his articles apply directly to your problem, but you may see something that will help. MVVM related articles [ http://kentb.blogspot.com/search/label/MVVM ] if you search for Truss, you will even find a nifty Plain Old C# Object [Poco] binding framework that he wrote.
      singulars
      1. POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
      1. USjohnny g
    2. COI wonder if this sort of problem will be fixed by Olso?
      singulars
      1. POHow have you combined the advantages of the direct View-to-Model approach and MVVM in your WPF projects?
      1. USSchneider
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload