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C# WPF - variable value won't display on Textboxes (DataContext?)

I got a really tricky and annoying problem with my C# WPF Application. I guess it's not a big deal for a good programmer to solve it, but I don't know how to fix it yet. For school, I have to program an application which depicts a process. So I get Data by an XML-File, have to calculate some values, display them for User Interaction etc. and at the end the output is again a file, which can be processed further.
For that, I got different UserControls, which depicts different modules for example, one for the Data Import, the other one for calculating and displayng values and so on. The Main Window is like the free space or the place-maker on which the different modules are loaded depending on where we are in the process.
My problem now is that the values I calculate in my UserControl won't display in my UI respectively my application and I don't really know why. 0 is the only value which is transferred to the application. Curious about it, is that in the Debugger the values are correct, but in the display itself there is only a 0.
Ok, so I show you now the code of the different files (I'm not the best programmer, so maybe the code is sometimes a bit dirty).
I got a Main UserControl, let's call it UC_Main, and in this UserControl you can switch between 3 different other UserControls depending on which Radiobutton in the UC_Main is checked. (The UC_Main is always displayed, because in this there are only the 3 radio buttons and underneath is a big free space, where the different UserControls 1, 2 and 3 are loaded).
UC_Main.xaml
<UserControl.Resources>
<DataTemplate x:Name="UC1_Template" DataType="{x:Type local:UC1}">
<local:UC1 DataContext="{Binding}" />
</DataTemplate>
<DataTemplate x:Name="UC2_Template" DataType="{x:Type local:UC2}">
<local:UC2 DataContext="{Binding}" />
</DataTemplate>
<DataTemplate x:Name="UC3_Template" DataType="{x:Type local:UC3}">
<local:UC3 DataContext="{Binding}" />
</DataTemplate>
</UserControl.Resources>
<Border Padding="10">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<!-- In the First Row there are the radio buttons in the second the
different UserControls 1, 2 or 3 -->
<Grid.RowDefinitions>
<RowDefinition Height="50"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<materialDesign:ColorZone Mode="PrimaryMid" Width="400" HorizontalAlignment="Left">
<StackPanel Grid.Row="0" Orientation="Horizontal" Margin="2">
<RadioButton x:Name="UC1_radiobutton" Checked="UC1_radiobutton_Checked"
Style="{StaticResource MaterialDesignTabRadioButton}"
Margin="4"
IsChecked="True"
Content="UserControl1" />
<RadioButton x:Name="UC2_radiobutton" Checked="UC2_radiobutton_Checked"
Style="{StaticResource MaterialDesignTabRadioButton}"
Margin="4"
IsChecked="False"
Content="UserControl2" />
<RadioButton x:Name="UC3_radiobutton" Checked="UC3_radiobutton_Checked"
Style="{StaticResource MaterialDesignTabRadioButton}"
Margin="4"
IsChecked="False"
Content="UserControl3" />
</StackPanel>
</materialDesign:ColorZone>
<ContentControl Grid.Row="1" Content="{Binding}" />
</Grid>
</Border>
</UserControl>
UC_Main.xaml.cs
public partial class UC_Main : UserControl
{
public UC_Main()
{
InitializeComponent();
}
private void UC1_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC1();
}
private void UC2_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC2();
}
private void UC3_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC3();
}
}
}
To keep it simple, I'll only show you the Code of UserControl 1, because UC 2 and 3 are pretty the same beside other variables or values.
UC1.xaml
<Border Padding="10">
<StackPanel>
<!-- To keep the example simple, I got 1 Row and 2 Colums; in each
is one TextBox -->
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="2*" />
<ColumnDefinition Width="2*" />
</Grid.ColumnDefinitions>
<TextBox x:Name="TextBox1" Grid.Column="0" IsTabStop="False"
Text="{Binding Path=variable1, Mode=TwoWay}"
VerticalAlignment="Center"
HorizontalAlignment="Center"
TextAlignment="Center"
Height="25"
Width="85"
Foreground="DarkGray"
IsReadOnly="True" />
<TextBox x:Name="TextBox2" Grid.Column="1" IsTabStop="False"
Text="{Binding Path=variable2, Mode=TwoWay}"
VerticalAlignment="Center"
HorizontalAlignment="Center"
TextAlignment="Center"
Height="25"
Width="85"
Foreground="DarkGray"
IsReadOnly="True" />
</Grid>
</StackPanel>
</Border>
</UserControl>
UC_1.xaml.cs
public partial class UC1 : UserControl
{
public MainWindow Speaker;
public ValueStore vs;
public UC1()
{
InitializeComponent();
Speaker = MainWindow.AppWindow;
vs = new ValueStore();
DataContext = vs;
}
public void calc_data()
{
// I get the data from the data import (XML-File), which is saved in
// a dictionary (strings), converting them to int (so I can do some
// math operations) and save them in my variable.
// UC_Other is a UserControl, where the data import happens
// dict_other is the dictionary, where the data from the import is
// saved
vs.variable1 =
Convert.ToInt32(MainWindow.AppWindow.UC_other.dict_other["0"].Amount);
vs.variable2 =
Convert.ToInt32(MainWindow.AppWindow.UC_other.dict_other["1"].Amount);
}
I call the function calc_data() in an UserControl before, so the data gets calculated and saved in my variables before my UserControl shows up. I declare a new public instance of my UC1 and call the function via UC1.calc_data(); (which is linked to a Button, that is loading my UC_Main).
ValueStore.cs
public class ValueStore : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string name)
{
if(PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
private int _variable1;
public int variable1
{
get { return _variable1; }
set { _variable1 = value; OnPropertyChanged("variable1"); }
}
private int _variable2;
public int variable2
{
get { return _variable2; }
set { _variable2 = value; OnPropertyChanged("variable2"); }
}
When I look in the debugger after the method calc_data() is called, the values are correct saved in my ValueStore instance and the TextBoxes are showing me in the Debugger that the correct value is in there (the Debugger says "Name: TextBox1" and "Value: {System.Windows.Controls.TextBox: 100}"; 100 is the value I got from the dictionary), but in my application itself there is only the value 0 displayed.
What I don't really understand is, when I change the type from variable1 to string in my ValueStore.cs and save it in my variable in the method calc_data()(without Convert.ToInt32), it doesn't even show a 0 any more in my application, but in the debugger there is still the value "100".

There are a few things here, but my best guess why your debugging-values are correct while none are updated to the GUI is here:
public partial class UC_Main : UserControl
{
public UC_Main()
{
InitializeComponent();
}
private void UC1_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC1();
}
private void UC2_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC2();
}
private void UC3_radiobutton_Checked(object sender, RoutedEventArgs e)
{
DataContext = new UC3();
}
}
You are creating new instances of these classes of the code-behind to the usercontrols. But the usercontrol objects are already created by the UC_Main.xaml so during runtime, you have two objects for example of the UC1 class, one which is your bound to your GUI and one where you store and update your values. The one you see on your GUI doesn't get any values updates, which is why you aren't seeing anything.
I currently can't test the code myself, but from what I can see that is where the issue lies.
Furthermore it is a bit confusing to me, why you are using databinding for code-behind.
(You are using the code-behind of the UC-classes as datacontext for the main class, which is....weird ;) I think in your case no databinding whatsoever is really needed, however if you want to do stuff with databinding you should probably read up on MVVM)

UWP update a itemscontrol with an array that keeps updating

I have an array that keeps changing its values, because of this I want to have the apps UI refreshing every time the array's values do. I have this bound with an itemsControl. I can show the first array's values but then I can't update them I have tried .items.Clear() but its not working. Here are snippets of the .xaml and the xaml.cs. I actually took the code of the .xaml from a question from this site.
.xaml
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
<TextBox Text="Testing" IsReadOnly="True"></TextBox>
<ItemsControl x:Name="itemsControl"
ItemsSource="{Binding itemsControl}"
FontSize="24">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Width="Auto"
Margin="0 12"
HorizontalAlignment="Center">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<StackPanel Grid.Column="0"
Grid.Row="0"
Orientation="Horizontal">
<TextBlock Name="txtblk0" Text="{Binding}" />
</StackPanel>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
.xaml.cs
String c = (new String(cArray));
string[] arr = null;
string[] data = null;
if (c != null)
{
arr = c.Split('\n');
if (arr.Length > 0)
{
data = arr[0].Split(',');
}
}
for(int index = 0; index < 4; index++)
{
itemsControl.Items.Add(float.Parse(data[index]));
}
itemsControl.Clear();
If anyone has an idea of how I can do this I will be very grateful, thanks in advance and I will try to answer any questions as soon as possible!

What you're missing is an understanding of how bindings are triggered to update.
The INotifyPropertyChanged interface contains a method (PropertyChanged) and when called and passed the name of a property will tell the binding system that the property has changed and the binding should be updated.
INotifyCollectionChanged is the equivalent for collections, and communicates when a collection has changed. i.e. something added, removed, or the list cleared.
ObservableCollection<T> contains an implementation of INotifyCollectionChanged that makes it easy to work with lists, collections, etc. that change.
If you used an ObservableCollection<float> instead of an array you'd be able to modify the list and have the UI updated to reflect this easily.
As a starter, see the following which demonstrates how easy it is to use an ObservableCollection.
XAML:
<StackPanel>
<Button Click="Button_Click">add an item</Button>
<ItemsControl ItemsSource="{Binding Items}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
code behind;
public MainPage()
{
this.InitializeComponent();
// Initialize the property
this.Items = new ObservableCollection<string>();
// Use self as datacontext (but would normally use a separate viewmodel)
this.DataContext = this;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
// add a new item to the UI
this.Items.Add(DateTime.Now.ToString());
}
// The "collection" that is shown in the UI
public ObservableCollection<string> Items { get; set; }

Binding Command to ItemsControl Item

I am working on a Win10 UWP app using MVVMLight (I've never used MVVMLight, and never done commands "properly"). I have an ItemsControl bound to an ObservableCollection. The Participant has two properties - Name and Laps. I have controls in the ItemsControl.ItemTemplate to display a button (subtract), the Name property of the item, the Laps property of the item, and another button (add). Here is the XAML:
<ItemsControl
ItemsSource="{Binding Participants, Mode= TwoWay}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid
MinWidth="300"
Margin="0, 12">
<Grid.ColumnDefinitions>
<ColumnDefinition
Width="2*"></ColumnDefinition>
<ColumnDefinition
Width="6*"></ColumnDefinition>
<ColumnDefinition
Width="2*"></ColumnDefinition>
<ColumnDefinition
Width="3*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Button
Content=""
FontFamily="Segoe MDL2 Assets"
FontSize="20"
Grid.Column="0"
Margin="0, 0, 12, 0"></Button>
<TextBlock
Text="{Binding Path=Name, Mode=TwoWay}"
FontSize="20"
FontWeight="Bold"
Grid.Column="1"></TextBlock>
<TextBlock
Text="{Binding Laps, Mode=TwoWay}"
FontSize="20"
FontWeight="Bold"
Grid.Column="2"></TextBlock>
<Button
Content=""
FontFamily="Segoe MDL2 Assets"
FontSize="20"
Command="{Binding AddLapCommand}"
CommandParameter="{Binding}"
Grid.Column="3"
Margin="12, 0, 0, 0"></Button>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
The view model creates an ObservableCollection called Participants. I am trying to bind the add button (and then of course the subtract button) to a RelayCommand in the VM. I've tried a number of things, so I can't post all I've tried here. Here is the latest of what I have, (but it still doesn't work):
public RelayCommand<object> AddLapCommand
{
get
{
if (_addLapCommand == null)
{
_addLapCommand = new RelayCommand<object>((e) => ExecuteAddLapCommand(e));
}
return _addLapCommand;
}
}
private void ExecuteAddLapCommand(object o)
{
throw new NotImplementedException();
}
The intellisense in the xaml tells me that it cannot resolve the property AddLapCommand in data context of type LapCounter.Model.Participant. I'm not trying to get to the Participant class, but to the HomeViewModel class, which is the DataContext of the page. I think I can see where it is getting the LapCounter.Model.Participant from, from the individual item in the collection that the ItemsControl is bound to. But I was under the impression that if a DataContext couldn't be found, it would continue up the visual tree until it found the right one. Here's the DataContext in the page declaration:
DataContext="{Binding Home, Source={StaticResource Locator}}"
How do I get it to look at the VM for the RelayCommand? What I need to do is have the button send the Participant that it represents to the RelayCommand as a parameter, and use that to increment (and decrement in the case of the subtract button) the Laps integer for that particular Participant.
I appreciate any help I can get. Thanks!
EDIT
Added Participants property from the VM to show because my view is not updating. Here is the Participants property:
/// <summary>
/// The <see cref="Participants" /> property's name.
/// </summary>
public const string ParticipantsPropertyName = "Participants";
private ObservableCollection<Participant> _participants = new ObservableCollection<Participant>();
/// <summary>
/// Sets and gets the Participants property.
/// Changes to that property's value raise the PropertyChanged event.
/// </summary>
public ObservableCollection<Participant> Participants
{
get
{
return _participants;
}
set
{
if (_participants == value)
{
return;
}
_participants = value;
RaisePropertyChanged(() => Participants);
}
}
Thanks to Eldar Dordzhiev for his help so far!

Try this:
Command="{Binding Home.AddLapCommand, Source={StaticResource Locator}}"
There's not much to explain to you as long as everything you've written is absolutely right.
As for incrementing\decrementing the Laps, you can simply pass the Participant into the command handler and alter the Laps. If you use MVVMLight that is done with RelayCommand<Participant>. Don't forget to pass the Participant in CommandParameter.

Can I swap a buttons content databind to a different databind in code?

I cannot find any examples to make me understand how and if I can change the databind in c# at the click of a button on, in my case a toggleswitch, Basically I have 32 buttons in my app and those 32 buttons act the same but need different text with-in them depending on some toggle switches they are currently databinded so the text can be saved and retrieved from local storage but what values it gets depends on the state of these toggle switches.
So I currently have :
<Button x:Name="_ovButton1" Content="{Binding Source={StaticResource AppSettings}, Path=ovName1_1Value, Mode=TwoWay}" Margin="2,0,250,0" VerticalAlignment="Top" FontSize="14" Height="72" FontWeight="Bold" MouseLeftButtonUp="_ovButton1_MouseLeftButtonUp" MouseLeftButtonDown="_ovButton1_MouseLeftButtonDown" ClickMode="Hover" Hold="_ovButton1_Hold"/>
and I want when a user changes the state of a toggleswitch to change the
{StaticResource AppSettings}, Path=ovName1_1Value, Mode=TwoWay}
to for example:
{StaticResource AppSettings}, Path=ovName1_2Value, Mode=TwoWay}
but I cannot find any example that shows how to do that in c#
what code do I need to do that?

You can specify the target of databinding in code like this:
MyData myDataObject = new MyData(DateTime.Now);
Binding myBinding = new Binding("MyDataProperty");
myBinding.Source = myDataObject;
myText.SetBinding(TextBlock.TextProperty, myBinding);
See more at http://msdn.microsoft.com/en-us/library/ms742863.aspx

-- Edit Note I don't have access to a WP8 Emulator to test this ---
In the view model it looks like this:
public List<string> Members
{
get { return _Members; }
set { _Members = value; OnPropertyChanged(); }
}
public MainVM()
{
// Simulate Asychronous access, such as to a db.
Task.Run(() =>
{
Thread.Sleep(2000);
Members = new List<string>() {"Alpha", "Beta", "Gamma", "Omega"};
});
}
The code behind on the main page sets the datacontext (shared with all the child controls) as such:
public MainWindow()
{
InitializeComponent();
// Set the windows data context so all controls can have it.
DataContext = new MainVM();
}
The Mainpage Xaml to bind to members is like this
<Button Height="30"
Width="80"
Margin="10"
DataContext="{Binding Members}"
Content="{Binding Path=[0] }" />
<Button Height="30"
Width="80"
Margin="10"
DataContext="{Binding Members}"
Content="{Binding Path=[1] }" />
<Button Height="30"
Width="80"
Margin="10"
DataContext="{Binding Members}"
Content="{Binding Path=[2] }" />
<Button Height="30"
Width="80"
Margin="10"
DataContext="{Binding Members}"
Content="{Binding Path=[3] }" />
The result is this visually:
I based this on my blog article Xaml: ViewModel Main Page Instantiation and Loading Strategy for Easier Binding for more info and a fuller example.

I think your best bet is going to be to use a collection of strings and bind to that collection. You can either change the collection when a toggle is switched, or keep 6 collections and bind to the collection that is for the toggle.
Xaml:
<ItemsControl x:Name="Buttons" ItemsSource="{Binding ButtonTextCollection}">
<ItemsControl.ItemsPanel>
<toolkit:WrapPanel/>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Width="100" Height="70" Content="{Binding}" Click="OnButtonClick"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Your code-behind would have the event handler for your button click
private void OnButtonClick(object sender, RoutedEventArgs e)
{
var text = ((Button) sender).Content.ToString();
// Send the text
}
Your ViewModel would hold the ButtonTextCollection property and would change based on the toggle.
public ICollection<string> ButtonTextCollection
{
get { return _buttonTextCollection; }
set
{
_buttonTextCollection = value;
OnPropertyChanged("ButtonTextCollection");
}
}
When you want to change the text, you would change the ButtonTextCollection
public void ChangeButtonText()
{
ButtonTextCollection = new Collection<string> {"A", "B",...};
}

How can I raise a custom Routed Event from a DataTemplate?

I have a User Control,called dCB_Props that contains several objects, most importantly a ComboBox that's bound to an Observable Collection. Though the collection can take any object, it will normally take a UserControl called EditDeleteItem. I've set dCB_Props to use EditDeleteItem as an ItemsTemplate but the events aren't fired. If, on the other hand, I add an instance of EditDeleteItem then the events will get fired. I can't add items this way because the EditDeleteItem will host other controls and I'd need to use different DataTemplates.
EditDeleteItem has two Routed Events called EditClick and DeleteClick.
When the collection changes it fires an event that checks if the item added is of type EditDeleteItem. If so, then it adds handlers to the two aforementioned events.
Part of the xaml for EditDeleteClick:
<WrapPanel x:Name="wp" HorizontalAlignment="Right" Visibility="Hidden" VerticalAlignment="Center" Margin="0,0,5,0">
<Button x:Name="PART_Edit" Width="20" Height="20" Content="{DynamicResource dPen}" Style="{DynamicResource dTranspButton}" Click="btnEdit_Click"/>
<Button x:Name="PART_Delete" Width="20" Height="20" Content="{DynamicResource dCross}" Style="{DynamicResource dTranspButton}" Click="btnDelete_Click"/>
</WrapPanel>
<Label Content="{TemplateBinding Content}" Margin="2,0,45,0" Padding="0,0,0,0" HorizontalAlignment="Left" VerticalContentAlignment="Center"/>
Part of the xaml for dCB_Props:
<ComboBox HorizontalContentAlignment="Stretch" x:Name="PART_cb" Background="Transparent" Margin="0,0,0.367,0" d:LayoutOverrides="HorizontalAlignment" ItemsSource="{Binding Items, ElementName=dcb}" IsDropDownOpen="{Binding IsDropDownOpen,ElementName=dcb, Mode=TwoWay}" Grid.ColumnSpan="3" Style="{DynamicResource DaisyComboBox}" />
<Button x:Name="PART_Edit" Width="20" Height="20" Content="{DynamicResource dPen}" Visibility="Hidden" Style="{DynamicResource dTranspButton}" Margin="2.581,1.48,17.778,-1.48" Grid.Column="1" Click="btnEdit_Click"/>
<Button x:Name="PART_Delete" Width="20" Height="20" Content="{DynamicResource dCross}" Visibility="Hidden" Margin="22.602,1.48,-2.243,-1.48" Style="{DynamicResource dTranspButton}" Grid.Column="1" Click="btnDelete_Click"/>
<Button x:Name="PART_Add" Content="+" Grid.Column="3" Margin="0,0,0,0" Style="{DynamicResource dTranspButton}" Click="btnAdd_Click"/>
Note the above two are codes just for objects, I've left out Column Definitions, Event Triggers, etc.
Part of dCB_Props.xaml.cs code is:
public partial class dCB_Props : UserControl
{
public dCB_Props()
{
this.InitializeComponent();
Items= new ObservableCollection<object>();
Items.CollectionChanged += new System.Collections.Specialized.NotifyCollectionChangedEventHandler(Items_CollectionChanged);
}
void Items_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
if (e.Action == System.Collections.Specialized.NotifyCollectionChangedAction.Add)
{
foreach (var o in e.NewItems)
{
if (o.GetType() == typeof(EditDeleteItem))
{
EditDeleteItem itm = (EditDeleteItem)o;
itm.EditClick += new RoutedEventHandler(ItemEdit_Click);
itm.DeleteClick += new RoutedEventHandler(ItemDelete_Click);
}
}
}
}
...//I've left some code here since I don't deem it's that important for the situation
private void ItemEdit_Click(object sender, RoutedEventArgs e)
{
DependencyObject d = GetTemplateChild("PART_cb");
if (d == null) return;
ComboBox cb = (ComboBox)d;
if (cb.SelectedItem != null) RaiseEvent(new RoutedEventArgs(EditClickEvent, e.OriginalSource));
}
}
The above works if I add an item of type EditDeleteItem and remove the ItemTemplate property for the Label that resides inside dCB_Props. It also works if I set the ItemTemplate, shown below, in EditDeleteItem's ContentTemplate. But, as mentioned, I need to use different Data Templates so I assume all Data Templates will have to reside in a Resource Dictionary and then I'd have to use a Template Selector.
Data Template:
<DataTemplate x:Shared="false" x:Key="TagTemplate">
<local:EditDeleteItem x:Name="edItem">
<local:EditDeleteItem.Content>
<StackPanel>
<TextBlock Text="{Binding Path=Content.Label}"/>
<CheckBox Content="Isolated" IsChecked="{Binding Content.IsIsolated}"/>
<CheckBox Content="Match Case" IsChecked="{Binding Content.MatchCase}"/>
<CheckBox Content="Include" IsChecked="{Binding Content.Include}"/>
</StackPanel>
</local:EditDeleteItem.Content>
</local:EditDeleteItem>
</DataTemplate>
I believe I need to use command bindings. But not really sure where to put the CommandBindings, and not so sure how to use them, though I've read a page or two.
Thanks,
Hassan

The events are fired, but you don't catch them, because subscription in Items_CollectionChanged never occurs if ItemTemplate is used.
You should understand how ItemsControl (and ComboBox) works with ItemsSource. ItemsControl use ItemContainerGenerator to populate its visual tree. Each item from ItemsSource wrap into container which derived from ContentControl. Then item is set as a Content, ItemTemplate is set as ContentTemplate and so on. When you put EditDeleteItem into ItemTemplate it becomes a part of visual tree but not an item. That's why there is no EditDeleteItem in e.NewItems and no subscription.
The right way is Commands, as you mentioned. You should declare two commands:
public class EditDeleteItem : UserControl
{
...
public static readonly RoutedUICommand EditCommand = new RoutedUICommand(...);
public static readonly RoutedUICommand DeleteCommand = new RoutedUICommand(...);
...
}
Now the part of template may look like:
<WrapPanel ...>
<Button ... Command="{x:Static EditDeleteItem.EditCommand}"/>
<Button ... Command="{x:Static EditDeleteItem.DeleteCommand}"/>
</WrapPanel>
Then you add command bindings to dCB_Props:
public partial class dCB_Props : UserControl
{
static dCB_Props()
{
...
CommandManager.RegisterClassCommandBinding(
typeof(dCB_Props),
new CommandBinding(EditDeleteItem.EditCommand, OnEditCommandExecuted));
CommandManager.RegisterClassCommandBinding(
typeof(dCB_Props),
new CommandBinding(EditDeleteItem.DeleteCommand, OnDeleteCommandExecuted));
...
}
...
}
You need to implement OnEditCommandExecuted and OnDeleteCommandExecuted in order to handle corresponding commands from EditDeleteItem.
I hope I understood your question correctly ;)