Develop Reference

Wpf bind property in ItemContainerStyle to TextBlock in DataTemplate of ItemTemplate

I want to bind AutomationProperties.Name to text that containd in secondTextBox how to do that? Using only xaml without code behind.
Xaml:
<Window x:Class="WpfApplication5.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WpfApplication5"
xmlns:converters="clr-namespace:WpfApplication5.Converters"
mc:Ignorable="d"
Title="TestWindow" Height="350" Width="525">
<Window.Resources>
<converters:StrangeConverter x:Key="CommonConverter"/>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid Grid.Row="0">
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<ComboBox Height="20" Width="100" ItemsSource="{Binding comboBoxItems}" AutomationProperties.AutomationId="ID_COMBO1">
<ComboBox.ItemContainerStyle>
<Style>
<!--<Setter Property="AutomationProperties.Name" Value="{Binding UniqNumber}"/>-->
<Setter Property="AutomationProperties.Name" Value="{Binding Path=Text, ElementName=secondTextBox}"/>
</Style>
</ComboBox.ItemContainerStyle>
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock x:Name="secondTextBox">
<Run Text="{Binding Name}"></Run>
<Run Text="-"></Run>
<Run Text="{Binding UniqNumber}"></Run>
<Run Text="{Binding .,Converter={StaticResource CommonConverter}}"></Run>
</TextBlock>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
</Grid>
<ComboBox Height="20" Width="100" ItemsSource="{Binding comboBoxItems}" AutomationProperties.AutomationId="ID_COMBO2"/>
<Button Grid.Row="1" Height="20" Width="100" Click="Button_Click"/>
</Grid>
</Window>
Converter:
namespace WpfApplication5.Converters
{
class StrangeConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
return "Test";
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
}
Code:
namespace WpfApplication5
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
ViewModel Vm = new ViewModel();
public MainWindow()
{
InitializeComponent();
DataContext = Vm;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
var _calculatorAutomationElement = AutomationElement.RootElement.FindFirst(TreeScope.Children, new PropertyCondition(AutomationElement.NameProperty, "TestWindow"));
var combobox = _calculatorAutomationElement.FindFirst(TreeScope.Subtree, new PropertyCondition(AutomationElement.AutomationIdProperty, "ID_COMBO1"));
Vm.SelectComboboxItem(combobox, "02 - Basic Get");
combobox = _calculatorAutomationElement.FindFirst(TreeScope.Subtree, new PropertyCondition(AutomationElement.AutomationIdProperty, "ID_COMBO2"));
Vm.SelectComboboxItem(combobox, "01 - Basic Set");
}
}
public class ViewModel
{
public List<Item> comboBoxItems { get; set; }
public ViewModel()
{
comboBoxItems = new List<Item>();
comboBoxItems.Add(new Item { Name = "Basic Get", UniqNumber = 1 });
comboBoxItems.Add(new Item { Name = "Basic Set", UniqNumber = 2 });
comboBoxItems.Add(new Item { Name = "Basic Report", UniqNumber = 3 });
}
public bool SelectComboboxItem(AutomationElement comboBox, string item)
{
(comboBox.GetCurrentPattern(ExpandCollapsePattern.Pattern) as ExpandCollapsePattern).Expand();
PropertyCondition findCondition = new PropertyCondition(AutomationElement.NameProperty, item);
var comboBoxItems = comboBox.FindFirst(TreeScope.Children, findCondition);
if (comboBoxItems != null)
{
var selectionItemPattern = comboBoxItems.GetCurrentPattern(SelectionItemPattern.Pattern) as SelectionItemPattern;
selectionItemPattern.Select();
return true;
}
return false;
}
}
public class Item
{
public string Name { get; set; }
public int UniqNumber { get; set; }
}
}

Update the Item class as:
public class Item
{
private string _TextToDisplay;
public string Name { get; set; }
public int UniqNumber { get; set; }
public string TextToDisplay
{
get
{
_TextToDisplay = Name + "-" + UniqNumber; //Add other modification from converter
return _TextToDisplay;
}
set
{
_TextToDisplay = value;
}
}
}
Bind the AutomationProperties.Name to this property
<TextBlock x:Name="secondTextBox" Text="{Binding TextToDisplay}" AutomationProperties.Name="{Binding TextToDisplay}">

This should work without additional view model property and without converter:
<ComboBox.ItemContainerStyle>
<Style TargetType="ComboBoxItem">
<Setter Property="AutomationProperties.Name">
<Setter.Value>
<MultiBinding StringFormat="{}{0} - {1} Test">
<Binding Path="Name"/>
<Binding Path="UniqNumber"/>
</MultiBinding>
</Setter.Value>
</Setter>
</Style>
</ComboBox.ItemContainerStyle>
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock>
<TextBlock.Text>
<MultiBinding StringFormat="{}{0} - {1} Test">
<Binding Path="Name"/>
<Binding Path="UniqNumber"/>
</MultiBinding>
</TextBlock.Text>
</TextBlock>
</DataTemplate>
</ComboBox.ItemTemplate>

How to bind a Command to a ContextMenu from within an ItemTemplate?

I want to bind a certain command to a menuItem. The said menu item is part of a ContextMenu that is defined inside an ItemTemplate.
Right now, what I have compiles and runs, but the command is never called. In the past, I had used a similar pattern to hook commands to buttons defined in an ItemTemplate with success.
Anyone has any idea how I could accomplish this?
XAML:
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Wpf_treeView" x:Name="window" x:Class="Wpf_treeView.MainWindow"
Title="MainWindow" Height="350" Width="525">
<Grid>
<TreeView HorizontalAlignment="Left" Height="299" Margin="10,10,0,0" VerticalAlignment="Top" Width="228" ItemsSource="{Binding DataInfosView}" >
<TreeView.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Children}">
<TextBlock DockPanel.Dock="Left" Text="{Binding InfoValue}" TextAlignment="Left" >
<TextBlock.ContextMenu>
<ContextMenu>
<MenuItem Header="{Binding InfoValue}" IsEnabled="False"/>
<MenuItem Header="Add child" Command="{Binding AddChildCmd, ElementName=window}"/>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
</TreeView>
</Grid>
</Window>
C#:
using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Data;
using System.Windows.Input;
namespace Wpf_treeView
{
public partial class MainWindow : Window
{
private static readonly Random rnd = new Random();
private List<InfoData> m_InfoData = new List<InfoData>();
public ListCollectionView DataInfosView { get; private set; }
public static readonly DependencyProperty AddChildProperty =
DependencyProperty.Register("AddChildCmd",
typeof(ICommand),
typeof(MainWindow));
public ICommand AddChildCmd
{
get { return (ICommand) GetValue(AddChildProperty); }
set { SetValue(AddChildProperty, value); }
}
public MainWindow()
{
AddChildCmd = new RoutedCommand();
CommandManager.RegisterClassCommandBinding(
GetType(),
new CommandBinding(AddChildCmd, AddChild));
m_InfoData.Add(new InfoData(4));
m_InfoData.Add(new InfoData(1));
m_InfoData.Add(new InfoData(5));
m_InfoData[1].Children.Add(new InfoData(3));
m_InfoData[1].Children[0].Children.Add(new InfoData(7));
DataInfosView = new ListCollectionView(m_InfoData);
DataContext = this;
InitializeComponent();
}
private void AddChild(object sender, RoutedEventArgs e)
{
ExecutedRoutedEventArgs args = (ExecutedRoutedEventArgs)e;
InfoData info = (InfoData)args.Parameter;
info.Children.Add(new InfoData(rnd.Next(0, 11)));
}
}
class InfoData : INotifyPropertyChanged
{
private int infoValue;
public int InfoValue
{
get { return infoValue; }
set
{
if (value != infoValue)
{
infoValue = value;
OnPropertyChanged();
}
}
}
public List<InfoData> Children { get; private set; }
public InfoData(int infoValue)
{
InfoValue = infoValue;
Children = new List<InfoData>();
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(
[CallerMemberName] string propertyName = null)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}

Alright this should work:
<TextBlock DockPanel.Dock="Left"
Text="{Binding InfoValue}"
TextAlignment="Left"
Tag="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}}}">
<TextBlock.ContextMenu>
<ContextMenu>
<MenuItem Header="{Binding InfoValue}"
IsEnabled="False" />
<MenuItem Header="Add child"
Command="{Binding Path=Parent.PlacementTarget.Tag.AddChildCmd, RelativeSource={RelativeSource Self}}"
CommandParameter="{Binding}" />
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
The ContextMenu doesn't exist in the regular Visual Tree, so you aren't able to walk up the tree to get to the main data context. By using the Tag you are able to "pass in" the Main Window's data context to the context menu. For some more information on binding with context menu's see this answer as well as this one as they provide some good explanations as to what is going on

WPF - MVVM : How to Check/Uncheck all Items in a ListView

I have the following requirements:
Window will show a ListView with multiple items.
User should be able to check (Checkbox) any item.
a) If one item, all items should be unchecked and disabled.
b) If checked item is unchecked, than all items should be enabled.
As of now, I have the following incomplete code.
MainWindow XAML:
<Window x:Class="WpfApplication4.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="520.149" Width="732.463">
<Window.Resources>
<ResourceDictionary Source="MainWindowResource.xaml" />
</Window.Resources>
<Grid>
<ListView x:Name="myListBox" ItemTemplate="{StaticResource OfferingTemplate}">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="3" VerticalAlignment="Top"/>
</ItemsPanelTemplate>
</ListView.ItemsPanel>
</ListView>
</Grid>
</Window>
DataTemplete for ListView:
<DataTemplate x:Key="OfferingTemplate">
<StackPanel>
<Grid IsEnabled="{Binding IsEnabled}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="8"></ColumnDefinition>
<ColumnDefinition Width="120"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="40"></RowDefinition>
<RowDefinition Height="50"></RowDefinition>
<RowDefinition Height="30"></RowDefinition>
</Grid.RowDefinitions>
<Rectangle Grid.Column="0" Grid.RowSpan="3" Fill="#F4CA16" />
<Label
Grid.Column="1"
Grid.Row="0"
Content="{Binding Title}"
FontSize="18" FontWeight="Bold"
Margin="0,0,0,0" />
<TextBlock
Grid.Column="1"
Grid.Row="1"
FontSize="10"
Text="{Binding Description}"
Foreground="Black"
TextWrapping="WrapWithOverflow"
Margin="5,0,0,0" />
<CheckBox
Grid.Column="1"
Grid.Row="2"
FontSize="14"
IsChecked="{Binding IsSelected}"
VerticalAlignment="Bottom"
Margin="5,0,0,0">
<TextBlock Text="Select" Margin="0,-2,0,0"/>
</CheckBox>
</Grid>
</StackPanel>
</DataTemplate>
Model:
class MyModel
{
public string Title { get; set; }
public string Description { get; set; }
public bool IsSelected { get; set; }
public bool IsEnabled { get; set; }
}
ViewModel:
class MyViewModel : INotifyPropertyChanged
{
private MyModel offering;
public MyViewModel()
{
offering = new MyModel();
}
public int ID { get; set; }
public string Title
{
get { return offering.Title; }
set
{
offering.Title = value;
RaisePropertyChanged("Title");
}
}
public string Description
{
get { return offering.Description; }
set
{
offering.Description = value;
RaisePropertyChanged("Description");
}
}
public bool IsSelected
{
get { return offering.IsSelected; }
set
{
offering.IsSelected = value;
RaisePropertyChanged("IsSelected");
}
}
public bool IsEnabled
{
get { return offering.IsEnabled; }
set
{
offering.IsEnabled = value;
RaisePropertyChanged("IsEnabled");
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string propertyName)
{
var handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(propertyName));
}
}
}

This is an interesting question. Since the action you want applies to all items in the list, this logic should in list class level. Your MyViewModel class is fine. You need add some logic in your list class and XAML but thanks to Prism, it is quite easy.
The list class (not shown in your post) Contains:
public ObservableCollection<MyViewModel> MyItems { get; set; } //Binding to ItemsSource
private ICommand _selectCommand;
public ICommand SelectCommand
{
get { return _selectCommand ?? (_selectCommand = new DelegateCommand<MyViewModel>(DoSelect)); }
}
private void DoSelect(MyViewModel myViewModel)
{
foreach(var item in MyItems)
if (item != myViewModel)
{
item.IsSelected = false;
item.IsEnabled = false;
}
}
private ICommand _unselectCommand;
public ICommand UnselectCommand
{
get { return _unselectCommand ?? (_unselectCommand = new DelegateCommand<MyViewModel>(DoUnselect)); }
}
private void DoUnselect(MyViewModel myViewModel)
{
foreach (var item in MyItems)
if (item != myViewModel)
{
item.IsEnabled = true;
}
}
There are two commands, one for selecting and the other for unselecting. The magic is on XAML:
<ListView ItemsSource="{Binding Path=MyItems}" x:Name="listView">
<ListView.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding Path=IsSelected}" IsEnabled="{Binding Path=IsEnabled}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Checked">
<i:InvokeCommandAction Command="{Binding ElementName=listView, Path=DataContext.SelectCommand}"
CommandParameter="{Binding}"/>
</i:EventTrigger>
<i:EventTrigger EventName="Unchecked">
<i:InvokeCommandAction Command="{Binding ElementName=listView, Path=DataContext.UnselectCommand}"
CommandParameter="{Binding}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</CheckBox>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Using Prism's triggers, you can map CheckBox's Checked and Unchecked event to your list view model's commands and passing the item view model as parameter.
It is working perfectly but one thing is annoying, that setting item's IsSelected is separate. When you check a CheckBox, the item behind is set to true through DataBinding but all others are set through parent view model. If your post is all your requirement, you can remove IsChecked binding and put the logic of setting one IsSelected inside list view model, which looks clenaer and easier to write test code.

Why this Button Command Binding is not working?

I did this like 50 times before. I really don't know why it is not working this time. I have a WPF application and my only dependency is MahApps.Metro. I'm using it's MetroWindow and Dynamic Style on my Button.
Here is the latest xaml:
<ItemsControl Grid.Column="0" Grid.Row="1" ItemsSource="{Binding ServerList}" Margin="5">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Border Background="LightGray">
<StackPanel Orientation="Horizontal">
<Button Style="{DynamicResource MetroCircleButtonStyle}" Content="{StaticResource appbar_monitor}" Command="{Binding VM.ServerSelectedCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Controls:MetroWindow}}" CommandParameter="{Binding .}"></Button>
<Label Content="{Binding .}" HorizontalAlignment="Center" VerticalAlignment="Center"></Label>
</StackPanel>
</Border>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Here is my ServerSelectedCommand in my ViewModel:
private ViewModelCommand _ServerSelectedCommand;
public ViewModelCommand ServerSelectedCommand
{
get
{
if (_ServerSelectedCommand == null)
{
_ServerSelectedCommand = new ViewModelCommand(
p => { SelectServer(p); },
p => true
);
}
return _ServerSelectedCommand;
}
set { _ServerSelectedCommand = value; }
}
private void SelectServer(object parameter)
{
}
ViewModelCommand class is like RelayCommand. Here it is:
public class ViewModelCommand : Observable, ICommand
{
public bool CanExecuteValue
{
get { return CanExecute(null); }
}
public ViewModelCommand(
Action<object> executeAction,
Predicate<object> canExecute)
{
if (executeAction == null)
throw new ArgumentNullException("executeAction");
_executeAction = executeAction;
_canExecute = canExecute;
}
private readonly Predicate<object> _canExecute;
public bool CanExecute(object parameter)
{
return _canExecute == null ? true : _canExecute(parameter);
}
public event EventHandler CanExecuteChanged;
public void OnCanExecuteChanged()
{
OnPropertyChanged(() => CanExecuteValue);
if (CanExecuteChanged != null)
CanExecuteChanged(this, EventArgs.Empty);
}
private readonly Action<object> _executeAction;
public void Execute(object parameter)
{
_executeAction(parameter);
}
}
Sorry for a lot of code. But I need to add them in order to find the problem which I can't see. So lets turn back to first xaml, that is the latest one I tried. Here are the codes that I tried for problematic Button line.
Command="{Binding ServerSelectedCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ItemsControl}}"
Command="{Binding ServerSelectedCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type local:ViewModel}}}"
This also doesn't provide anything!
Command="{Binding RelativeSource={RelativeSource AncestorType=Controls:MetroWindow}}"
Thanks!

This binding looks like it is looking for ServerSelectedCommand on the ItemsControl:
Command="{Binding ServerSelectedCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ItemsControl}}"
try this instead:
Command="{Binding DataContext.ServerSelectedCommand, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ItemsControl}}"
Assuming of course that the DataContext of the ItemsControl is your ViewModel.

Data Binding Not Working Properly

In this program, I'm able to add one tab at a time by clicking the "Add Course" button. Ideally, the header of the tab should be the course name I entered and the text in the textbox , which is on the tab, should display the course name.
However, it's not functioning correctly. When I tried to add more than 1 tabs, each time it gives me this error message:
System.Windows.Data Error: 40 : BindingExpression path error: 'Text' property not found on 'object' ''MyHomeworkViewModel' (HashCode=33010577)'. BindingExpression:Path=Text; DataItem='MyHomeworkViewModel' (HashCode=33010577); target element is 'TextBox' (Name=''); target property is 'Text' (type 'String')
Also, it seems to "override" other tab's text (just text, not header). For example, if I add a tab with header "a", the text of that is also "a". Then if I add "B", both textboxes on two tabs become "B". However, if I print out the Text property of each tab (MyHomeworkModel in this case), they are "a" and "B", respectively.
I have been debugging this whole day but no luck. Any help would be appreciated!
My View (DataContext set to MyHomeworkViewModel):
<Window x:Class="MyHomework__MVVM_.MyHomeworkView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="My Homework" Height="450" Width="800" ResizeMode="CanMinimize">
<Grid Margin="0,0,10,10">
<TabControl HorizontalAlignment="Left" Height="330" VerticalAlignment="Top" Width="764" Margin="10,10,0,0" ItemsSource="{Binding AllTabs}" SelectedItem="{Binding SelectedTab}">
<TabControl.ItemContainerStyle>
<Style TargetType="TabItem">
<Setter Property="Header" Value="{Binding Header}"/>
<Setter Property="Content">
<Setter.Value>
<Grid>
<TextBox Text="{Binding Text}" FontSize="16" AcceptsReturn="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
</TextBox>
</Grid>
</Setter.Value>
</Setter>
<Setter Property="FontSize" Value="20"/>
</Style>
</TabControl.ItemContainerStyle>
</TabControl>
<Button Content="Add Course" HorizontalAlignment="Left" VerticalAlignment="Top" Width="105" Margin="10,351,0,0" Height="50" Command="{Binding AddCourseCommand}"/>
<Button Content="Drop Course" HorizontalAlignment="Left" VerticalAlignment="Top" Width="76" Margin="138,379,0,0" Height="22" Command="{Binding DropCourseCommand, UpdateSourceTrigger=PropertyChanged}"/>
<Button Content="Save HW" HorizontalAlignment="Left" VerticalAlignment="Top" Width="105" Margin="669,351,0,0" Height="50"/>
</Grid>
</Window>
My Model:
using System.ComponentModel;
namespace MyHomework__MVVM_
{
class MyHomeworkModel : INotifyPropertyChanged
{
private string header, text;
public event PropertyChangedEventHandler PropertyChanged;
public string Header
{
get
{
return header;
}
set
{
header = value;
OnPropertyChanged("Header");
}
}
public string Text
{
get
{
return text;
}
set
{
text = value;
OnPropertyChanged("Text");
}
}
private void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
My ViewModel:
using MyHomework;
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows.Input;
namespace MyHomework__MVVM_
{
class MyHomeworkViewModel : INotifyPropertyChanged
{
private ObservableCollection<MyHomeworkModel> allTabs;
private MyHomeworkModel selectedTab;
private MyHomeworkView mainWindow;
public event PropertyChangedEventHandler PropertyChanged;
public MyHomeworkViewModel(MyHomeworkView mainWindow)
{
allTabs = new ObservableCollection<MyHomeworkModel>();
this.mainWindow = mainWindow;
AddCourseCommand = new AddCourseCommand(this);
DropCourseCommand = new DropCourseCommand(this);
}
public ObservableCollection<MyHomeworkModel> AllTabs
{
get
{
return allTabs;
}
set
{
allTabs = value;
OnPropertyChanged("AllTabs");
}
}
public MyHomeworkModel SelectedTab
{
get
{
return selectedTab;
}
set
{
selectedTab = value;
OnPropertyChanged("SelectedTab");
}
}
public ICommand AddCourseCommand
{
get;
private set;
}
public ICommand DropCourseCommand
{
get;
private set;
}
public void AddNewTab()
{
NewCourseName ncn = new NewCourseName();
ncn.Owner = mainWindow;
ncn.ShowDialog();
if (ncn.courseName != null)
{
MyHomeworkModel newTab = new MyHomeworkModel();
newTab.Header = ncn.courseName;
newTab.Text = ncn.courseName;
AllTabs.Add(newTab);
SelectedTab = newTab;
}
foreach (MyHomeworkModel item in AllTabs)
{
Console.WriteLine(item.Text);
}
}
public bool CanDrop()
{
return SelectedTab != null;
}
public void RemoveTab()
{
DropCourseConfirmation dcc = new DropCourseConfirmation();
dcc.Owner = mainWindow;
dcc.ShowDialog();
if (dcc.drop == true)
{
int index = AllTabs.IndexOf(SelectedTab);
AllTabs.Remove(SelectedTab);
if (AllTabs.Count > 0)
{
if (index == 0)
{
SelectedTab = AllTabs[0];
}
else
{
SelectedTab = AllTabs[--index];
}
}
else
{
SelectedTab = null;
}
}
}
private void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
Please let me know if you need more codes to help me.

Change your
<Setter Property="Content">
<Setter.Value>
<Grid>
<TextBox Text="{Binding Text}" FontSize="16" AcceptsReturn="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
</TextBox>
</Grid>
</Setter.Value>
</Setter>
for this:
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<Grid>
<TextBox Text="{Binding Text}" FontSize="16" AcceptsReturn="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
</TextBox>
</Grid>
</DataTemplate>
</Setter.Value>
</Setter>

Your DataContext isn't what you think it is. Read the error there. It states that "Text" is not a valid property on MyHomeworkViewModel which is true (As opposed to your MyHomeworkModel).
What you need to be modifying instead of the ItemContainerStyle is instead the ItemTemplate and the ContentTemplate which uses the appropriate object within your ItemsSource as its DataContext.
Additionally, the binding in your TextBox needs to be Text="{Binding Text, Mode=TwoWay}" or it won't modify the property in your model.