将多个视图绑定到多个视图模型

Question

I have a WPF window displaying different self-defined Views. So far I was able to use everything I learned about MVVM :)

Now I got to a new "problem": I have 10 entities of the same view in a bigger view. These ten view-entities contain a set of controls (textbox, combobox etc.) but are all consistent.

So how do I bind these Views to a ViewModel?

I thought about having 10 instances of the ViewModel in the "higher-level" ViewModel and give the views fix-defined the instances of the VM as datacontext.

My question is now --> Is there a easier (or more convienient) way to bind many (identical) views to their viewmodels?

Code-Example:

View Model:

private PanelViewModel _panelViewModel1 = new PanelViewModel();
public PanelViewModel PanelVM1
{
   get { return _panelViewModel1; }
}  

View-Example:

<myControls:vwPanel HorizontalAlignment="Left" x:Name="vwPanel1" 
                    VerticalAlignment="Top" DataContext="{Binding Path=PanelVM1}"/>

What bothers me is that I would need this logic ten times for ten views?

UPDATE: To answer some questions: I want to show one view 10 times (in my example) I defined my own view by inheriting from UserControl. So my vwPanel inherits from UserControl . The 10 vwPanels are just placed inside a StackPanel inside a Grid.

It's not about displaying data, as you pointed out, there would be a listview or a datagrid a better place to start. It's a special case where I need this much input-controls :/

UPDATE2: What I hoped for was more like defining a List of ViewModels and Bind my 10 Views to one of this List. But this will not work will it? At least I wouldn't know how to refernce one "special" entitiy in the list out of XAML...

Answer 1

Typically I use implicit DataTemplates for mapping Views to ViewModels . They can go in <Application.Resources> , <Window.Resources> or even in under specific elements only such as <TabControl.Resources>

<DataTemplate DataType="{x:Type local:PanelViewModel}">
    <myControls:vwPanel />
</DataTemplate>

This means that anytime WPF encounters an object in the VisualTree of type PanelViewModel , it will draw it using vwPanel

Objects typically get placed in the VisualTree through an ItemsSource property

<ItemsControl ItemsSource="{Binding CollectionOfAllPanels}" />

or by using a ContentControl

<ContentControl Content="{Binding PanelVM1}" />

Answer 2

If I understand your question correctly, you have a collection of something that you what to represent visually. That is, you have several viewmodels that you want to define a single view for, but show X number of times. Your example shows you using a panel as your view for the "PanelViewModel"...what is the parent item's control for the vwPanel? Assuming you're using something like a ListBox, you can define a custom DataTemplate that contains your vwPanel and assign that DataTemplate to your ListBox.ItemTemplate.

For example:

<Window.Resources>
    <DataTemplate x:Key="myVMTemplate" TargetType="{x:Type myViewModels:PanelViewModel}">
        <myControls:vwPanel HorizontalAlignment="Left" VerticalAlignment="Top"/>
    </DataTemplate>
</Window.Resources>

<ListBox ItemsSource="{Binding Path=MyCollectionOfPanelVMs}" 
         ItemTemplate="{StaticResource myVMTemplate}" />

I haven't verified that this works.