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WPF c# Relative Source Ancestor Data Binding

I have a main window with a user control in a content control
<MainWindow Title="MainWindow">
<!-- MainWindows DataContext is set to MainWindowViewModel -->
<ContentControl Content="{Binding CurrentViewModel}">
<ContentControl.Resources>
<DataTemplate DataType="{x:Type viewmodels:ViewModel1}">
<local:UserControl1/>
</DataTemplate>
</ContentControl.Resources>
<ContentControl/>
<MainWindow/>
And a User Control with a text box
<UserControl Title="UserControl1">
<TextBlock Text="{Binding Path=Words}"/>
<UserControl/>
And a MainWindowViewModel
public class MainWindowViewModel
{
private ViewModelBase _currentViewModel;
public ViewModelBase CurrentViewModel
{
get { return _currentViewModel; }
set
{
_currentViewModel = value;
OnPropertyChanged("CurrentViewModel");
}
}
private string _words;
public string Words
{
get { return _words; }
set
{
_words = value;
OnPropertyChanged("Words");
}
}
}
How do I bind the textblocks text to the Words property?
I tried this but it isnt working...
<TextBlock Text="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContentControl}}, Path=DataContext.Words}" />

WPF change notification of user control inside item template not working

I'm trying to bind each view model in an ObservableCollection<FilterControlViewmodel> as DataContext to a user control FilterControl in an ItemsControl.
The binding itself works fine. "InitialFilterName" is displayed correctly from FilterControlViewmodel.FilterName but any updates on the property are not notified to the UI.
Also adding elements to ObservableCollection<FilterControlViewmodel> is working find and adding additional user controls. But again the values inside the FilterControlViewmodel are not updated to the UI.
Any hint on where the notification is missing is appreciated. Thanks.
MainWindow.xaml
<Window.DataContext>
<local:MainWindowViewmodel/>
</Window.DataContext>
<Grid>
<ItemsControl ItemsSource="{Binding FilterViewmodel.FilterControls}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<filter:FilterControl DataContext="{Binding}"></filter:FilterControl>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
FilterControl.xaml
<UserControl.DataContext>
<local:FilterControlViewmodel/>
</UserControl.DataContext>
<Grid>
<Label Grid.Column="0" Grid.Row="0" Content="{Binding FilterName}"></Label>
<ComboBox Grid.Column="0" Grid.Row="1" ItemsSource="{Binding FilterValues}" SelectedItem="{Binding FilterValueSelected}"></ComboBox>
<Button Grid.Column="1" Grid.Row="1" Content="X" Command="{Binding ResetFilterCommand}"></Button>
</Grid>
MainWindowViewmodel.cs
public class MainWindowViewmodel : INotifyPropertyChanged
{
public FilterViewmodel FilterViewmodel
{
get => _filterViewmodel;
set
{
if (Equals(value, _filterViewmodel)) return;
_filterViewmodel = value;
OnPropertyChanged();
}
}
FilterViewmodel.cs
public class FilterViewmodel : INotifyPropertyChanged
{
public ObservableCollection<FilterControlViewmodel> FilterControls
{
get => return _filterControls;
set
{
if (Equals(value, _filterControls)) return;
_filterControls = value;
OnPropertyChanged();
}
}
FilterControlViewmodel.cs
public class FilterControlViewmodel : INotifyPropertyChanged
{
private string _filterName = "InitialFilterName";
public string FilterName
{
get => _filterName;
set
{
if (value == _filterName) return;
_filterName = value;
OnPropertyChanged();
}
}

You should remove the following markup as it creates another instance of FilterControlViewmodel:
<UserControl.DataContext>
<local:FilterControlViewmodel/>
</UserControl.DataContext>
The FilterControl will then inherit its DataContext from the current item (FilterControlViewmodel) in the ItemsControl without you having to set the DataContext property explicitly:
<ItemsControl ItemsSource="{Binding FilterViewmodel.FilterControls}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<filter:FilterControl/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

TabItem Content IsEnabled binding

I'm creating a WPF application using MVVM pattern (at least I'm trying). There is <TabControl> with bound ItemsSource,which is an ObservableCollection<TabModel> Tabs. Tabs has Name and Items property, where Items is a list of ControlModel, which means Controls. I have problem with binding IsEnabled property to Grid where Items are placed.
Below there is a part of my code presenting the way I'm doing this:
private ObservableCollection<TabModel> tabs;
public ObservableCollection<TabModel> Tabs
{
get
{
if (tabs == null)
{
tabs = new ObservableCollection<TabModel>();
RefreshTabs();
}
return tabs;
}
set
{
tabs = value;
OnPropertyChanged("Tabs");
}
}
\\Tab Model
public string Name { get; set; }
private List<ControlModel> items;
public List<ControlModel> Items
{
get { return items; }
set
{
items = value;
OnPropertyChanged("Items");
}
}
And xaml...
<TabControl Margin="0,100,0,0" ItemsSource="{Binding Tabs,UpdateSourceTrigger=PropertyChanged}">
<TabControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}"/>
</DataTemplate>
</TabControl.ItemTemplate>
<TabControl.ContentTemplate>
<DataTemplate>
<ScrollViewer VerticalScrollBarVisibility="Hidden">
<Grid Margin="5,5,5,5" IsEnabled="{Binding IsProductEditionEnabled}">
<!--<Grid Margin="5,5,5,5">-->
<ItemsControl ItemsSource="{Binding Items,UpdateSourceTrigger=PropertyChanged}" ItemTemplateSelector="{StaticResource ControlTemplateSelector}"/>
</Grid>
</ScrollViewer>
</DataTemplate>
</TabControl.ContentTemplate>
The part...
<Grid Margin="5,5,5,5" IsEnabled="{Binding IsProductEditionEnabled}">
is not working. There is no error. This grid is always disabled. By default it's false.
private bool isProductEditionEnabled = false;
public bool IsProductEditionEnabled
{
get { return isProductEditionEnabled; }
set
{
isProductEditionEnabled = value;
OnPropertyChanged("IsProductEditionEnabled");
}
}
The question is : How to bind IsEnabled in my case properly?

You are inside a DataTemplate so you need to specify where the parent DataContext is when you do the binding, something like this:
<DataTemplate>
<ScrollViewer VerticalScrollBarVisibility="Hidden">
<Grid IsEnabled="{Binding Path=DataContext.IsProductEditionEnabled,
RelativeSource={RelativeSource AncestorType={x:Type TabControl}}}">
</Grid>
</ScrollViewer>
</DataTemplate>

TabControl not finding data templates for TabControl items

I am binding a collection of TabViewModel items to a TabControl. Each of these has a header string property, and a content property of my own custom type BaseTabContentViewModel, an abstract class which each actual tab data viewmodel implements. Eg ValuationTabViewModel which is a sub-class of BaseTabContentViewModel.
I add the new TabViewModel to the Observable<TabViewModel> for the TabControl to pick up and it shows in the UI. I have overridden style templates for the layout of the tab control and header which work fine. The only trouble is the content doesn't find the template in my resource dictionary based on its type, it just displays the full qualified class name of the viewmodel, showing that it is not finding a default template for this class.
Why isn't the ValuationTabViewModel that is being displayed, finding the datatemplate for this type below?
My main view model.
public ObservableCollection<TabViewModel> DetailTabs { get; }
var valuationTab = new TabViewModel(DetailTabConstants.ValuationTab, new ValuationTabViewModel(_eventAggregator, _errorNotifier, _windsorContainer));
DetailTabs = new ObservableCollection<TabViewModel> { valuationTab };
Main XAML
<TabControl Margin="0,-2,0,0" x:Name="SelectionTabs" Style="{StaticResource DetailTabControl}" ItemsSource="{Binding DetailTabs}"
SelectedValue="{Binding SelectedTab, Mode=TwoWay}" ItemContainerStyle="{StaticResource DetailTabItem}">
<TabControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}" />
</DataTemplate>
</TabControl.ItemTemplate>
<TabControl.ContentTemplate>
<DataTemplate>
<TextBlock Text="{Binding Content}" />
</DataTemplate>
</TabControl.ContentTemplate>
</TabControl>
The content style template I want it to use
<DataTemplate x:Key="ValuationTabTemplate" DataType="{x:Type detailTabs1:ValuationTabViewModel}" >
<detailTabs:ValuationTab Margin="0,10,0,10" />
</DataTemplate>
And my Tab item ViewModel class
public class TabViewModel : ViewModelBase
{
private string _header;
private BaseTabContentViewModel _content;
public string Header
{
get => _header;
set
{
_header = value;
RaisePropertyChanged(nameof(Header));
}
}
public BaseTabContentViewModel Content
{
get => _content;
set
{
_content = value;
RaisePropertyChanged(nameof(Content));
}
}
public TabViewModel(string header, BaseTabContentViewModel viewModel)
{
Header = header;
Content = viewModel;
}
}

Remove the <TabControl.ContentTemplate> element and define an implicit DataTemplate (without an x:Key) for each type:
<TabControl Margin="0,-2,0,0" x:Name="SelectionTabs" Style="{StaticResource DetailTabControl}" ItemsSource="{Binding DetailTabs}"
SelectedValue="{Binding SelectedTab, Mode=TwoWay}" ItemContainerStyle="{StaticResource DetailTabItem}">
<TabControl.Resources>
<DataTemplate DataType="{x:Type detailTabs1:ValuationTabViewModel}">
<detailTabs:ValuationTab Margin="0,10,0,10" />
</DataTemplate>
</TabControl.Resources>
<TabControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Header}" />
</DataTemplate>
</TabControl.ItemTemplate>
</TabControl>

I think your custom DataTemplate isn't being used because you have specified both a Key and a DataType for it, and the Key takes precedence.
As per the Microsoft docs:
... if you assign this DataTemplate an x:Key value, you are overriding the implicit x:Key and the DataTemplate would not be applied automatically
I would suggest removing the Key property and just using DataType:
<DataTemplate DataType="{x:Type detailTabs1:ValuationTabViewModel}">
...
</DataTemplate>
Also, as #mm8 implied, you are explicitly setting the ContentTemplate of your TabControl. You need to remove that from the XAML.

Binding SelectedItem in nested ListBox using Caliburn.Micro

I'm trying to use Caliburn.Micro to bind a view model of a nested ListBox but I'm stuck.
I have a list workspace that is divided in two sections a list of groups containtaining items in a different part of that workspace I want to show the details of either a group or an item in a group depending on what is the SelectedItem. I'm new to Caliburn.Micro and looked at the documentation and samples but don't know how to connect the dots. Specifically I'm trying to model this after the Caliburn.Micro.HelloScreens sample. The code I have so far:
The ViewModel:
public class AnalyzerGroupWorkspaceViewModel : Conductor<AnalyzerGroupWorkspaceViewModel>, IWorkspace
{
private Selected selected = Selected.AnalyzerGroup;
private const string name = "Analyzers";
public AnalyzerGroupWorkspaceViewModel(
IMappingEngine fromMapper,
IRepository<Model.AnalyzerGroup> analyzerGroups)
{
AnalyzerGroups = new ObservableCollection<IAnalyzerGroupViewModel>(analyzerGroups.GetAll().Select(fromMapper.Map<Model.AnalyzerGroup,AnalyzerGroupViewModel>));
}
public ObservableCollection<IAnalyzerGroupViewModel> AnalyzerGroups { get; private set; }
public string Name { get { return name; } }
public Selected Selected
{
get { return selected; }
set
{
if (value == selected) return;
selected = value;
NotifyOfPropertyChange(() => Selected);
}
}
private IConductor Conductor { get { return (IConductor) Parent; } }
public void Show()
{
var haveActive = Parent as IHaveActiveItem;
if (haveActive != null && haveActive.ActiveItem == this)
{
DisplayName = name;
Selected = Selected.AnalyzerGroup;
}
else
{
Conductor.ActivateItem(this);
}
}
}
The view:
<UserControl x:Class="Philips.HHDx.SSW.AnalyzerGroup.AnalyzerGroupWorkspaceView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.caliburnproject.org">
<DockPanel>
<GroupBox Header="AnalyzerGroups" DockPanel.Dock="Top">
<ListBox x:Name="AnalyzerGroups">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Vertical">
<TextBlock Text="{Binding Name}" />
<ListBox x:Name="Analyzers">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Id }"></TextBlock>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</GroupBox>
<GroupBox Header="Details">
<ContentControl cal:View.Context="{Binding Selected, Mode=TwoWay}"
cal:View.Model="{Binding}"
VerticalContentAlignment="Stretch"
HorizontalContentAlignment="Stretch"/>
</GroupBox>
</DockPanel>
</UserControl>
Next to that I have two UserControls that display the detailsof a group or item.
My specific question is how can I use the SelectedItem property of the two ListBoxes to modify the Selected property to switch between displaying the AnalyzerGroup details and the Analyzer details?

I've found the solution to the above described problem the solution consists of four parts:
Add a IsSelected property (that notifies changes) to both 'child' ViewModels
Bind the IsSelected property of the ListBox.ItemContainerStyle to the IsSelected property of the respective ViewModels
Attach a Caliburn.Micro Message to the 'outer' ListBox and use the $eventArgs argument
In the ViewModel bound to the entire UserControl implement the method corresponding to the Message and use the AddedItems property of the eventArgs to set the SelectedViewModel property setting the IsSelected property of the previous SelectedViewModel to false
The code then becomes:
The ViewModel:
public class AnalyzerGroupWorkspaceViewModel : PropertyChangedBase, IAnalyzerGroupWorkspaceViewModel
{
private IAnalyzerViewModel selectedViewModel;
private const string WorkspaceName = "Analyzers";
public AnalyzerGroupWorkspaceViewModel(
IMappingEngine fromMapper,
IRepository<Model.AnalyzerGroup> analyzerGroups)
{
AnalyzerGroups = new ObservableCollection<IAnalyzerGroupViewModel>(
analyzerGroups.GetAll().Select(
fromMapper.Map<Model.AnalyzerGroup, AnalyzerGroupViewModel>));
}
public void SelectionChanged(object eventArgs)
{
var typedEventArgs = eventArgs as SelectionChangedEventArgs;
if (typedEventArgs != null)
{
if (typedEventArgs.AddedItems.Count > 0)
{
var item = typedEventArgs.AddedItems[0];
var itemAsGroup = item as IAnalyzerViewModel;
if (itemAsGroup != null)
{
SelectedViewModel = itemAsGroup;
}
}
}
}
public ObservableCollection<IAnalyzerGroupViewModel> AnalyzerGroups { get; private set; }
public string Name { get { return WorkspaceName; } }
public IAnalyzerViewModel SelectedViewModel
{
get { return selectedViewModel; }
set
{
if (Equals(value, selectedViewModel))
{
return;
}
if (SelectedViewModel != null)
{
SelectedViewModel.IsSelected = false;
}
selectedViewModel = value;
NotifyOfPropertyChange(() => SelectedViewModel);
}
}
}
The View:
<UserControl x:Class="Philips.HHDx.SSW.AnalyzerGroup.AnalyzerGroupWorkspaceView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:cal="http://www.caliburnproject.org">
<DockPanel>
<GroupBox Header="AnalyzerGroups" DockPanel.Dock="Top">
<ListBox SelectionMode="Single"
x:Name="AnalyzerGroups"
cal:Message.Attach="[Event SelectionChanged] = [Action SelectionChanged($eventArgs)]">
<ListBox.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Border BorderThickness="2" BorderBrush="DarkGray">
<StackPanel Orientation="Vertical" Margin="10">
<TextBlock Text="{Binding Name}" />
<ListBox SelectionMode="Single" ItemsSource="{Binding Analyzers}" >
<ListBox.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<Setter Property="IsSelected" Value="{Binding IsSelected}"/>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"></StackPanel>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Border BorderThickness="1" BorderBrush="DarkGray">
<StackPanel>
<TextBlock Text="{Binding Name }" Margin="10" />
</StackPanel>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</GroupBox>
<GroupBox Header="Details">
<ContentControl cal:View.Model="{Binding SelectedViewModel}" />
</GroupBox>
</DockPanel>
</UserControl>

The answer to your specific question is yes, you can.
On the ViewModel of your UserControl. You create a property that is a ViewModel of either of the two details.
public interface IAnalyzerViewModel
{
}
Next, create two ViewModels for the Views of your Analyzer and AnalyzerGroup views.
public class AnalyzerGroupViewModel : IAnalyzerViewModel
{
}
public class AnalyzerViewModel : IAnalyzerViewModel
{
}
Next, create a property in your UserControl's ViewModel that implements INPC or PropertyChangedBase of Caliburn Micro.
public class MainViewModel :
{
private IAnalyzerViewModel _analyzerViewModel;
public IAnalyzerViewModel SelectedViewModel { get { return _analyzerViewModel; } set { _analyzerViewModel = value; OnPropertyChanged(() => SelectedViewModel); }
//Hook up the selected item changed event of your listbox and set the appropriate ViewModel to show, so if you either want to show the AnalyzerGroup or AnalyzerView.
}
And lastly, just update your MainView to
<ContentControl x:Name="SelectedViewModel"
VerticalContentAlignment="Stretch"
HorizontalContentAlignment="Stretch"/>
Caliburn will hook up the appropriate bindings and stuff and will pull the View for the associated ViewModel, and also the Name convention part will automatically map it to any public property of its datacontext as long as the names match.