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    <p>Hello I have a application design problem and I home you can help me solve it.... This is my first application in silverlight and the first application using mvvm design pattern and I am not sure I am applying mvvm how I am supposed to..</p> <p>The application is a dynamic application and at runtime I can add/remove usercontrols...</p> <p>So I have a MainWindowView that has behind a MainWindowModel.</p> <p>The MainWindowModel has a list of Workspaces witch are in fact WorkspaceModel classes...</p> <p>I have multiple UserControls and everyone off them has his own view model witch inherits WorkspaceModel. </p> <p>The Workspaces property is binded to a container in MainWindowView so adding to the Workspaces list a new UserControlModel will automatically add that control to the view. Now where is my problem... I want to make this dynamically added usercontrols to interact. Lets say one user control is a tree and one is a grid... I want a method to say that Itemsource property of Grid UserControl Model (WorkspaceModel) to be binded to SelectedNode.Nodes Property from the Tree Usercontrol Model (WorkspaceModel).</p> <p>The MainWindowModel has a property name BindingEntries witch has a list of BindingEntry... BindingEntry stores the source property and the destination property of the binding like my workspacemodel_1.SelectedNode.Nodes -> workspacemodel_2.ItemSource...</p> <p>Or as a variation the MainWindowView has a property ViewStateModel. This ViewStateModel class has dynamic created properties - "injected" with property type descriptors/reflections etc... So the user can define at run time the displayed usercontrols (by modifying the Workspaces list) and can define a view model (the ViewStameModel) and the binding is between workspacemodel properties and this ViewStateModel properties... </p> <p>So I actually want to bind 2 view models one to another... How to do that? Create an observer pattern? Is the design until now totally wrong?</p> <p>I hope it makes sense.....</p> <p>I will try to add some sample code...the project is quite big I will try co put only the part I have mentioned in the problem desciption... I hope I will not miss any pice of code</p> <p>First of all</p> <pre><code>public class MainWindowModel : ModelBase { private ObservableCollection&lt;WorkspaceModel&gt; _workspaces; private ModelBase _userViewModel; public MainWindowModel() { base.DisplayName = "MainWindowModel"; ShowTreeView(1); ShowTreeView(2); ShowGridView(3); ShowGridView(4); UserViewModel = new ViewModel(); //this is the ViewStateModel } void ShowTreeView(int id) { WorkspaceModel workspace = ControlFactory.CreateModel("TreeControlModel", id); this.Workspaces.Add(workspace); OnPropertyChanged("Workspaces"); SelectedWorkspace = workspace; } void ShowGridView(int id) { WorkspaceModel workspace = ControlFactory.CreateModel("GridControlModel", id); this.Workspaces.Add(workspace); OnPropertyChanged("Workspaces"); SelectedWorkspace = workspace; } public ObservableCollection&lt;WorkspaceModel&gt; Workspaces { get { if (_workspaces == null) { _workspaces = new ObservableCollection&lt;WorkspaceModel&gt;(); } return _workspaces; } } public ModelBase UserViewModel { get { return _userViewModel; } set { if (_userViewModel == value) { return; } _userViewModel = value; OnPropertyChanged("UserViewModel"); } } } </code></pre> <p>snippets from MainappView</p> <pre><code> &lt;DataTemplate x:Key="WorkspaceItemTemplate"&gt; &lt;Grid &gt; //workaround to use Type as in WPF &lt;Detail:DetailsViewSelector Content="{Binding}" TemplateType="{Binding}" &gt; &lt;Detail:DetailsViewSelector.Resources&gt; &lt;DataTemplate x:Key="TreeControlModel" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" &gt; &lt;TreeControl:TreeControlView /&gt; &lt;/DataTemplate&gt; &lt;DataTemplate x:Key="GridControlModel" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" &gt; &lt;GridControl:GridControlView /&gt; &lt;/DataTemplate&gt; &lt;DataTemplate x:Key="EmptyTemplate"&gt; &lt;/DataTemplate&gt; &lt;/Detail:DetailsViewSelector.Resources&gt; &lt;/Detail:DetailsViewSelector&gt; &lt;/Grid&gt; &lt;/DataTemplate&gt; &lt;DataTemplate x:Key="WorkspacesTemplate"&gt; &lt;ItemsControl IsTabStop="False" ItemsSource="{Binding}" ItemTemplate="{StaticResource WorkspaceItemTemplate}" Margin="6,2"/&gt; &lt;/DataTemplate&gt; &lt;/UserControl.Resources&gt; &lt;toolkit:HeaderedContentControl Grid.Column="2" HorizontalAlignment="Stretch" Name="hccWorkspaces" VerticalAlignment="Top" Header="Workspaces" Content="{Binding Source={StaticResource vm}, Path=Workspaces}" ContentTemplate="{StaticResource WorkspacesTemplate}"/&gt; public class ControlFactory { public static WorkspaceModel CreateModel(string type, int id) { switch (type) { case "TreeControlModel": return new TreeControlModel() { Id=id}; break; case "GridControlModel": return new GridControlModel() { Id = id }; break; } return null; } } public class GridControlModel : WorkspaceModel { #region Fields ObservableCollection&lt;TreeItem&gt; _items; TreeItem _selectedItem; #endregion // Fields #region Constructor public GridControlModel() { base.DisplayName = "GridControlModel"; } #endregion // Constructor #region Public Interface public ObservableCollection&lt;TreeItem&gt; Items { get { return _items; } set { if (_items == value) return; _items = value; OnPropertyChanged("Items"); } } public TreeItem SelectedItem { get { return _selectedItem; } set { if (_selectedItem.Equals(value)) { return; } _selectedItem = value; OnPropertyChanged("SelectedItem"); } } #endregion // Public Interface #region Base Class Overrides protected override void OnDispose() { this.OnDispose(); } #endregion // Base Class Overrides } </code></pre> <p></p> <pre><code> &lt;Grid x:Name="LayoutRoot" Background="White"&gt; &lt;sdk:DataGrid Grid.Column="2" Grid.Row="1" HorizontalAlignment="Stretch" Name="dataGrid1" VerticalAlignment="Stretch" ItemsSource="{Binding Path=SelectedTreeNode.Children}" IsEnabled="{Binding}" AutoGenerateColumns="False"&gt; &lt;sdk:DataGrid.Columns&gt; &lt;sdk:DataGridTextColumn CanUserReorder="True" CanUserResize="True" CanUserSort="True" Header="Id" Width="Auto" Binding="{Binding Id}" /&gt; &lt;sdk:DataGridTextColumn CanUserReorder="True" CanUserResize="True" CanUserSort="True" Header="Name" Width="Auto" Binding="{Binding Name}"/&gt; &lt;/sdk:DataGrid.Columns&gt; &lt;/sdk:DataGrid&gt; &lt;/Grid&gt; &lt;/UserControl&gt; </code></pre>
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    1. COWould you be having an easier time if you weren't focusing on fitting it into a pattern from a book?.. im really curious.
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    2. COSample code please...
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    3. CONobody reads such a long question, please make it short.
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