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ContentPresenter with ContentTemplateSelector inside an ItemTempate of an ItemsControl

So, I have an ItemsControl with an ItemTemplate to visualize the items in it's ItemsSource.
This Template is a DataTemplate with some controls in it.
<ItemsControl ItemsSource="{Binding Items}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock/>
<TextBlock/>
<!-- Content depending on item type -->
<ContentPresenter Content="{Binding}" ContentTemplateSelector="{StaticResource TemplateSelector}"/>
<TextBlock/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
The items in the ItemsSource can be of different types. Most of the properties of the different types are the same but some properties are different. So I want to put the common content directly inside the DataTemplate but for the content that differs I want to have some kind of placeholder that displays only type-specific content.
So I tried a ContentPresenter with a ContentTemplateSelector. But this does not work. When I set the Content, the TemplateSelector is never called and the name of the underlying viewmodel is displayed. When I do not set the Content, the TemplateSelector is called, but the item in the SelectTemplate function is null.
I do not want to make the whole DataTemplate for each DataType because most of the content is the same and I would have much duplicate code.

You do not need a DataTemplateSelector.
Just set the DataType of different DataTemplates in the ItemsControl's Resources. The DataTemplates would automatically be selected according to the type of the item.
<ItemsControl ItemsSource="{Binding Items}">
<ItemsControl.Resources>
<DataTemplate DataType="{x:Type local:Item1}">
<TextBlock Text="{Binding Item1Property}"/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:Item2}">
<TextBlock Text="{Binding Item2Property}"/>
</DataTemplate>
</ItemsControl.Resources>
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock ... />
<ContentPresenter Content="{Binding}"/>
<TextBlock ... />
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

Change visibility of one itemscontrol via checkbox in another

I have two ItemsControls with the same ItemsSource. One has some controls for each item, the other has a checkbox for each item. The controls in them are dynamically added. How can I bind the visibility of the first ItemsControls to the corresponding checkbox in the other ItemsControls ?
Here's the first ItemsControl containing multiple TextBlocks in the row. Note: I want to hide the whole row of controls.
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<TextBlock />
<TextBlock />
<TextBlock />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Here's the second ItemsControl with the checkboxes:
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<CheckBox Content="{Binding Name}"
IsChecked="True" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
So what happens is, for each item in VehicleCollection, a new row of textblocks is added for the first ItemsControl, and a checkbox is added for the second ItemsControl. These should relate to each other for example: If I uncheck the first checkbox, the first row for the other ItemsControl should be hidden.
I know how to do the booltovis converter, just not sure on how to relate these two ItemsControls.
Edit: These are both in the mainwindow.xaml by the way.

In order to show or hide an item of the first ItemsControl, add an IsVisible property to your Vehicle class (i.e. the element type of the VehicleCollection) and bind the Visibility of the item's ContentPresenter to the IsVisible property in an ItemContainerStyle:
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemContainerStyle>
<Style TargetType="ContentPresenter">
<Setter Property="Visibility"
Value="{Binding IsVisible,
Converter={StaticResource BooleanToVisibilityConverter}}"/>
</Style>
</ItemsControl.ItemContainerStyle>
<ItemsControl.ItemTemplate>
<DataTemplate>
...
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
In the other ItemsControl, bind the IsChecked property of the CheckBox to the IsVisible property:
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding Name}" IsChecked="{Binding IsVisible}"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Of course make sure that class Vehicle implements INotifyPropertyChanged and fires the PropertyChanged event when the IsVisible property changes.

You should be able to manage this by adding a boolean Property in your Vehicle class, which I presume is the basis for your VehicleCollection. Something like: IsSelected.
Then you can modify your XAML as shown below:
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<TextBlock Visibility="{Binding IsSelected,Converter={StaticResource boolToVisConverter}}"/>
<TextBlock Visibility="{Binding IsSelected,Converter={StaticResource boolToVisConverter}}"/>
<TextBlock Visibility="{Binding IsSelected,Converter={StaticResource boolToVisConverter}}"/>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<ItemsControl ItemsSource="{Binding VehicleCollection}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<CheckBox Content="{Binding Name}"
IsChecked="{Binding IsSelected}" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
This is untested XAML, as I just typed it into the answer. Might need a tweak.

How can I best display this nested collection? (Can you tell me why my code isn't working?)

Can you tell me why this code isn't working?
I have a viewmodel with an observablecollection of searchresults which has an observablecollection of resultproperties. I cannot seem to display the nested collection of result properties like I want.
Here are the objects (abstracted for readability):
class ViewModel
{
public ObservableCollection<SearchResults<TDomain>> SearchResults { get; set; }
}
class SearchResults<TDomain>
{
public TDomain Result { get; set; }
public ObservableCollection<ResultProperty> ResultProperties { get; set; }
}
class ResultProperty
{
public string PropertyValue { get; set; }
}
Here is the xaml I cannot get to work. The DataContext is set to the ViewModel:
<StackPanel>
<ItemsControl ItemsSource={Binding SearchResults}>
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text={Binding Result.Id}/>
<StackPanel Orientation="Horizontal">
<ItemsControl ItemsSource={Binding ResultProperties}>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding PropertyValue}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<TextBlock Text="PLACEHOLDER /////"/>
</StackPanel>
The outcome I am looking for is something like this:
[Stack panel to keep things orderly]
1
property1property2property3...
2
property1property2property3...
3
property1property2property3...
PLACEHOLDER /////
The results I am getting are these
[Stack panel to keep things orderly]
1
2
3
PLACEHOLDER /////
In otherwords, the binding isn't picking up the string. I have verified that the collections are populating like expected. But I can't get the xaml to work.
**ADDITION INFORMATION
Ok, so I tried some of the solutions, but they aren't working so I am going to add more details because maybe I am missing something about how the collections are getting updated.
The viewmodel has a button on it called "Search" which uses an ICommand that calls a the view model's TrySearch method which is below:
public void TrySearch()
{
var results = _model.GetAll();
foreach(var result in results)
this.SearchResults.Add(new SearchResults<TDomain>(result));
}
Could there be a reason this doesn't work because of the way the collection is updated? SearchResults is a dependency property (I know I know, it should be INPC, but its not, its dependency), but the other collections are not. Could this be a problem?

I would create the data templates as resources and refer to them elsewhere in the XAML. For example:
<Window ....>
<Window.Resources>
<DataTemplate x:Key="SearchResultTemplate" TargetType="SearchResults">
<TextBlock Text={Binding PropertyValue}"
</DataTemplate>
<DataTemplate x:Key="ViewModelTemplate" TartgetType="ViewModel">
<StackPanel>
<TextBlock Text={Binding Result.Id}/>
<StackPanel Orientation="Horizontal">
<ItemsControl ItemsSource={Binding ResultProperties} ItemTemplate="{StaticResource SearchResultTemplate}" />
</StackPanel>
</StackPanel
</DataTemplate>
</Window.Resources>
<StackPanel>
<ItemsControl ItemsSource={Binding SearchResults} ItemTemplate="{StaticResource ViewModelTemplate}" />
</Window>
I'm not sure, but I think that the bindings you're using are telling the XAML parser to look for properties of the ViewModel class called ResultProperties and PropertyValue. The XAML parser doesn't see that they're properties of the object bound to that instance of the collection. Splitting it up like this should make it plain that the properties belong to the instance that the template is being applied to.

Your code is somehow correct but according to what you want it has a flow. The StackPanel has to be the ItemsPanel. Change it like this:
<StackPanel>
<ItemsControl ItemsSource="{Binding SearchResults}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding Result.Id}"/>
<ItemsControl ItemsSource="{Binding ResultProperties}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" IsItemsHost="True"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding PropertyValue}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
<TextBlock Text="PLACEHOLDER /////"/>
</StackPanel>

The answer is that my SearchResults class was not hooked up properly. I made it a dependency object with dependency properties and it works fine. I am assuming that would translate similarly if it was INotifyPropertyChanged. Thank you for the responses.

Nested databinding with WPF and C#

I'm trying to make a budget program. Where I need to have groupboxes with a list of textblocks inside.
<ItemsControl DataContext="{Binding}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<GroupBox Header="{Binding}">
<ItemsControl DataContext="{Binding}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Text}" />
<TextBlock Text="{Binding Value}" />
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</GroupBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
I need somehow to databind a list (perhaps?) with groupboxes so I'd create a list of group boxes, with some lines inside that would be a text with a currency value. So that I could create a group called "Apartment", with two lines "Rent $3000" and "Maintenance $150". Then I could have a second group called "Car" with lines "Insurance", "Loan" and "Maintenance" for instance.
But how would I databind this? And how would I need in C# to perform this. I'm at a loss.

Building off of Jay's comment, you would want to create a Hierarchical data model. Note I have left implementing INotifyPropertyChanged on the properties to you
public class BudgetLineItem : INotifyPropertyChanged
{
public string Name { get; set; }
public decimal Cost { get; set; }
}
public class BudgetGroup : INotifyPropertyChanged
{
public string GroupName { get; set; }
public ObservableCollection<BudgetLineItem> LineItems { get; set; }
}
public class BudgetViewModel : INotifyPropertyChanged
{
public ObservableCollection<BudgetGroup> BudgetGroups { get; set; }
}
Then your data-template would look like this:
<ItemsControl DataContext="{Binding ViewModel}"
ItemsSource="{Binding BudgetGroups}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<GroupBox Header="{Binding GroupName}">
<ItemsControl ItemsSource="{Binding LineItems}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Name}" />
<TextBlock Text="{Binding Cost}" />
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</GroupBox>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

I could be off base here, but it sounds like you want to change the DataTemplate based on the type of object that is being bound from a list of heterogeneous objects.
If that's the case, you want to look into DataTemplateSelectors or create DataTemplates for each of the types you want to support in the list.
For example, for an Apartment you might have:
<DataTemplate DataType="local:ApartmentBudget">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Text}" />
<TextBlock Text="{Binding Value}" />
</StackPanel>
</DataTemplate>
a Car may look like:
<DataTemplate DataType="local:CarBudget">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Insurance}" />
<TextBlock Text="{Binding Loan}" />
<TextBlock Text="{Binding Maintenance}" />
</StackPanel>
</DataTemplate>
Then your ItemsControl can be set like:
<ItemsControl ItemSource="{Binding BudgetItems}">
The correct DataTemplate will be picked based on the data type. You can have even more control by creating a custom DataTemplateSelector.
See https://msdn.microsoft.com/en-us/library/ms742521(v=vs.100).aspx for more information.

How to achieve hierarchical data binding?

Learning WPF here and I'm trying to get my head around hierarchical data binding.
This is my situation:
public class A
{
public int Id { ... }
public IEnumerable<B> Children { ... }
}
public class B
{
public string SomeValue { ... }
}
I want to use a ItemsControl to display a collection of A and for each occurance of A I want an inner ItemsControl to display A.Children.
I thought this would do the trick but, apparently, I have much to learn yet...
<ItemsControl x:Name="icCollectionOfAs" ItemsSource="{Binding}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Width="auto" Height="auto">
<TextBlock Text="{Binding Id}" />
<ItemsControl ItemsSource="{Binding Children}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding SomeValue}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Then, in code-behind...
icCollectionOfAs.ItemsSource = createSomeAsWithChildBsInThem();
The result of all this is nothing gets shown. Why?
Thanks

You should not specify the ItemsSource both in XAML (ItemsSource="{Binding}") and code behind (icCollectionOfAs.ItemsSource = createSomeAsWithChildBsInThem();) the XAML might have been called later.
The rest seems fine to me except that the TextBlock for the ID will probably be hidden behind the ItemsControl for the children as you use a Grid without rows or columns rather than a StackPanel.