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How to insert items inside listbox withing another listbox on button click

I have a Listbox which is bound to a DataTemplate that has another Listbox on it.
On DataTemplate there is a button that I want to use for adding items to DataTemplate ListBox, but I can't find a solution to do this.
Here is my listbox:
<Button Width="200" Content="Add Question" x:Name="btnAddQuestion" Click="btnAddQuestion_Click"/>
<StackPanel Orientation="Horizontal">
<ListBox Margin="5" x:Name="lvQuestions" ItemTemplate="{StaticResource TemplateQuestionTitle}">
</ListBox>
</StackPanel>
And this is DataTemplate:
<DataTemplate x:Key="TemplateQuestionTitle">
<StackPanel Orientation="Vertical">
<StackPanel Orientation="Horizontal">
<TextBox materialDesign:HintAssist.Hint="Enter question" MinWidth="200" Style="{StaticResource MaterialDesignFloatingHintTextBox}"/>
<Button Content="+" Command="{Binding Source={x:Reference ThisPage},Path=DataContext.Command}" />
</StackPanel>
<ListBox ItemsSource="{Binding MyItems}" MinHeight="50">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox>
</TextBox>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</DataTemplate>
This is code behind on my page:
public partial class UIBuilder:Window
{
private CommandVm _commandVm;
public UIBuilder()
{
InitializeComponent();
_commandVm = new CommandVm();
DataContext = _commandVm;
}
private void btnAddQuestion_Click(object sender, RoutedEventArgs e)
{
lvQuestions.Items.Add(null);
}
}
I have implemented this code on my ViewModel in order to add items to datatemplate ListBox:
public class CommandVm
{
public ObservableCollection<TextBox> MyItems { get; set; }
public CommandVm()
{
MyItems = new ObservableCollection<TextBox>();
Command = new RelayCommand<TextBox>(Execute);
}
private void Execute(TextBox textBox)
{
MyItems .Add(textBox);
}
public ICommand Command { get; set; }
}
I use to catch the Execute() function on button "+" click command, but my code doesn't add any ListBox item.

MyItems is a property of the parent view model which means that you should bind to it like this:
<ListBox ItemsSource="{Binding DataContext.MyItems,
RelativeSource={RelativeSource AncestorType=Window}}" MinHeight="50">
This also means that you are using one single collection of items for all questions. Besides this obvious design flaw, a view model should not contain any TextBox elements. This basically breaks what the MVVM pattern is all about.
What you should do to make this example MVVM compliant is to create a Question class that has a collection of items, e.g.:
public class Question
{
public Question()
{
AddAnswerCommand = new RelayCommand<object>(Execute);
}
private void Execute(object obj)
{
Items.Add(new Answer());
}
public ObservableCollection<Answer> Items { get; }
= new ObservableCollection<Answer>();
public ICommand AddAnswerCommand { get; }
}
public class Answer { }
The window's view model should then have a collection of questions:
public class CommandVm
{
public CommandVm()
{
AddQuestionCommand = new RelayCommand<object>(Execute);
}
public ObservableCollection<Question> Questions { get; }
= new ObservableCollection<Question>();
public ICommand AddQuestionCommand { get; }
private void Execute(object obj)
{
Questions.Add(new Question());
}
}
The view and the bindings could then be defined like this:
<Window.Resources>
<DataTemplate x:Key="TemplateQuestionTitle">
<StackPanel Orientation="Vertical">
<StackPanel Orientation="Horizontal">
<TextBox MinWidth="200" />
<Button Content="+" Command="{Binding AddAnswerCommand}" />
</StackPanel>
<ListBox ItemsSource="{Binding Items}" MinHeight="50">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</DataTemplate>
</Window.Resources>
<StackPanel>
<Button Width="200" Content="Add Question" Command="{Binding AddQuestionCommand}"/>
<ListBox Margin="5"
ItemsSource="{Binding Questions}"
ItemTemplate="{StaticResource TemplateQuestionTitle}" />
</StackPanel>
This setup lets you add individual elements to each separate question.

How to show properties of listbox selected item in different controls

In my application I have a window which contain a ListBox, and controls that should show different properties of its currently selected item. Those controls are:
TextBox that should show 'Name' property.
TextBox that should show 'DataFile` property.
DataGrid that should show 'TItems property, which is an ObservableCollection.
I tried to bind SelectedItem to an object, and then bind different properties of that object to the controls mentioned above, with no success.
The window:
My View:
<Window
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:ReportMaker"
xmlns:ViewModel="clr-namespace:ReportMaker.ViewModel" x:Class="ReportMaker.MainWindow"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Window.DataContext>
<ViewModel:MainViewModel/>
</Window.DataContext>
<Grid>
<Button x:Name="button" Content="Create" HorizontalAlignment="Right" Margin="0,0,10,10" VerticalAlignment="Bottom" Width="75"/>
<ComboBox x:Name="comboBox" HorizontalAlignment="Left" Margin="10,0,0,10" VerticalAlignment="Bottom" Width="120"/>
<ListBox x:Name="listBox" HorizontalAlignment="Left" Margin="10,10,0,36.667" Width="119" ItemsSource="{Binding ReportItems}" >
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<StackPanel HorizontalAlignment="Left" Height="274" Margin="134,10,0,0" VerticalAlignment="Top" Width="375" DataContext="{Binding SelectedReportItem}">
<StackPanel.Resources>
<Style x:Key="ControlBaseStyle" TargetType="{x:Type Control}">
<Setter Property="Margin" Value="0, 10, 0, 0" />
</Style>
</StackPanel.Resources>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Name:"/>
<TextBox Width="150" Text="{Binding Name}"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Data File:"/>
<TextBox Width="150" Text="{Binding ID}"/>
</StackPanel>
<DataGrid Height="190" VerticalAlignment="Bottom" ItemsSource="{Binding TItems}"/>
</StackPanel>
<Button x:Name="button_Copy" Content="Save" HorizontalAlignment="Right" Margin="0,0,92,10" VerticalAlignment="Bottom" Width="75"/>
</Grid>
</Window>
My ViewModel:
public class MainViewModel
{
public ObservableCollection<ReportItem> ReportItems { get; set; }
public object SelectedReportItem { get; set; }
public MainViewModel()
{
ReportItems = new ObservableCollection<ReportItem>();
ReportItems.Add(Example);
}
public ReportItem Example = new TextReportItem() { Name = "John", DataFile = "try.txt"};
}
ReportItem:
public class ReportItem
{
public int Id { get; set; }
public string Name { get; set; }
public string DataFile { get; set; }
}
TextReportItem:
public class TextReportItem : ReportItem
{
public ObservableCollection<TextParcel> TItems { get; set; }
}
public class TextParcel
{
char Delimiter { get; set; }
string LineExp { get; set; }
string Result { get; set; }
string IgnoreLine { get; set; }
int DesiredResultIndexInLine { get; set; }
}
EDIT: as I use MVVM, I prefer to use only XAML in the View, with no code behind.
EDIT 2:
Thanks to S.Akbari I succeeded to view the desired properties in the TextBox controls, with the following code:
<StackPanel Orientation="Horizontal">
<TextBlock Text="Name:"/>
<TextBox Width="150" Text="{Binding ElementName=listBox, Path=SelectedItem.Name}"/>
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock Text="Data File:"/>
<TextBox Width="150" Text="{Binding ElementName=listBox, Path=SelectedItem.DataFile}"/>
</StackPanel>
But when the same logic is applied to my DataGrid, it fails for some reason:
<DataGrid Height="190" VerticalAlignment="Bottom" ItemsSource="{Binding ElementName=listBox, Path=SelectedItem.TItmes}" />
I also tried:
<DataGrid Height="190" VerticalAlignment="Bottom" DataContext="{Binding ElementName=listBox, Path=SelectedItem}" ItemsSource="{Binding TItems}"/>
And also:
<DataGrid Height="190" VerticalAlignment="Bottom" DataContext="{Binding ElementName=listBox, Path=SelectedItem}">
<DataTemplate>
<TextBlock Text="{Binding TItems}" />
</DataTemplate>
</DataGrid>

if you use MVVM your view model should raise property changed events
You should implement INotifyPropertyChanged
and change the selected item to be a full property
see :How to: Implement Property Change Notification

Binding to a Command from a DataTemplate in WPF

firstly thanks in advance for any help.
I have an application that i want to add a Navigation menu into. I have created a DataTemplate that has all my buttons and styling and I currently have that in my stylesheet.
<DataTemplate x:Key="Navigation">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="4*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<UniformGrid Grid.Row="0" Columns="1">
<Button Visibility="{Binding ElementName=Menu, Path=IsChecked, Converter={StaticResource VisibilityConverter}}" Style="{StaticResource MenuButtonStyle}" >Page 1</Button>
<Button Visibility="{Binding ElementName=Menu, Path=IsChecked, Converter={StaticResource VisibilityConverter}}" Style="{StaticResource MenuButtonStyle}" >Page 2</Button>
<Button Visibility="{Binding ElementName=Menu, Path=IsChecked, Converter={StaticResource VisibilityConverter}}" Style="{StaticResource MenuButtonStyle}" >Page 3</Button>
<Button Visibility="{Binding ElementName=Menu, Path=IsChecked, Converter={StaticResource VisibilityConverter}}" Style="{StaticResource MenuButtonStyle}" >Page 4</Button>
</UniformGrid>
<ToggleButton Grid.Row="1" Style="{StaticResource ToggleBtnToolStyle}" x:Name="Menu" IsChecked="true" Background="Transparent" BorderThickness="0" >
<StackPanel Orientation="Horizontal">
<ContentPresenter Margin="5" Height="50" Content="{StaticResource MenuIcon}"></ContentPresenter>
<Viewbox>
<TextBlock Margin="5" Style="{StaticResource TxtToolStyle}">Menu</TextBlock>
</Viewbox>
</StackPanel>
</ToggleButton>
</Grid>
</DataTemplate>
Currently the only way i have been able to get this working is to remove it from the DataTemplate and implement the grid on each page.
Is there a way of binding to my NavigationViewModel from my DataTemplate that is stored in my Stylesheet?
I'm sorry if this question is badly worded, I'm new to WPF and can do the basic data binding but I'm lost here.
Thanks
Edit
The ViewModel with the Commands i would like to link to looks like this
public abstract class NavigationViewModelBase : ViewModelBase
{
private List<DicomMetadataModel> _dicomMetadata;
//Navigation Cmd
public ICommand AcquisitionPageCmd { get; private set; }
public ICommand ManualEntryWindowCmd { get; private set; }
public ICommand SessionWindowCmd { get; private set; }
public ICommand SettingsWindowCmd { get; private set; }
public ICommand StudyInfoPageCommandCmd { get; private set; }
public ICommand ViewerPageCmd { get; private set; }
public ICommand WorklistPageCmd { get; private set; }
protected NavigationViewModelBase()
{
AcquisitionPageCmd = new RelayCommand(() => Messenger.Default.Send(new GoToPageMessage(Pages.AcquisitionScreen)));
ManualEntryWindowCmd = new RelayCommand(() => Messenger.Default.Send(new ShowDialogMessage(Pages.ManualEntry, DicomMetadata)));
SessionWindowCmd = new RelayCommand(() => Messenger.Default.Send(new ShowDialogMessage(Pages.Session)));
SettingsWindowCmd = new RelayCommand(() => Messenger.Default.Send(new ShowDialogMessage(Pages.Settings)));
ViewerPageCmd = new RelayCommand(() => Messenger.Default.Send(new GoToPageMessage(Pages.Viewer)));
WorklistPageCmd = new RelayCommand(() => Messenger.Default.Send(new GoToPageMessage(Pages.Worklist)));
}
}
}
And them in every page i would like to add the Navigation Menu into the code will look like this
<ContentControl Grid.Column="2" Grid.Row="2" Content="{Binding}" ContentTemplate="{StaticResource Navigation }" />

Binding data to WPF UserControl

I have creating following GridRow as UserControl
<UserControl x:Class="Project.Telematics_Plugin.GridRow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d" BorderBrush="LightBlue"
MaxHeight="30" MinWidth="900">
<Grid>
<StackPanel Orientation="Horizontal">
<CheckBox VerticalAlignment="Center" IsChecked="{Binding IsChecked}" />
<TextBox Width="60" Text="{Binding EventId}"/>
<TextBox Width="300" Text="{Binding MethodName}" />
<ComboBox Width="200" ItemsSource="{Binding }" />
<ComboBox Width="200"/>
<ComboBox Width="200"/>
<Button Click="OnClickEdit">
<Image Source="Images/edit.png"/>
</Button>
<Button Click="OnClickDelete">
<Image Source="Images/delete.png"/>
</Button>
</StackPanel>
</Grid>
</UserControl>
Here is the code behind
public partial class GridRow : UserControl
{
public bool IsChecked { get; set; }
public int EventId { get; set; }
public string MethodName { get; set; }
public string Level { get; set; }
public string Opcode { get; set; }
public string Task { get;set; }
public string Keyword { get; set; }
public GridRow()
{
InitializeComponent();
}
private void OnClickEdit(object sender, RoutedEventArgs e)
{
}
private void OnClickDelete(object sender, RoutedEventArgs e)
{
}
}
Now can you please tell what important thing I missed to bind properties of code behind files to UI in TwoWay Mode..
Although this is not the MVVM way..

Add an x:Name to your control and bind to the properties using ElementName:
<UserControl x:Name="MyGridRow">
<Grid>
<StackPanel Orientation="Horizontal">
<CheckBox VerticalAlignment="Center" IsChecked="{Binding IsChecked, ElementName=MyGridRow}" />
<TextBox Width="60" Text="{Binding EventId, ElementName=MyGridRow}"/>
<TextBox Width="300" Text="{Binding MethodName, ElementName=MyGridRow}" />
<ComboBox Width="200" ItemsSource="{Binding Path=., ElementName=MyGridRow}" />
<ComboBox Width="200"/>
<ComboBox Width="200"/>
<Button Click="OnClickEdit">
<Image Source="Images/edit.png"/>
</Button>
<Button Click="OnClickDelete">
<Image Source="Images/delete.png"/>
</Button>
</StackPanel>
</Grid>
</UserControl>
If you want to support updating the values, you should use DependencyProperties instead of normal properties:
public static readonly DependencyProperty IsCheckedProperty = DependencyProperty.Register("IsChecked", typeof(bool), typeof(GridRow));
public bool IsChecked
{
get { return (bool)GetValue(IsCheckedProperty); }
set { GetValue(IsCheckedProperty, value); }
}

when the DataContext where you use your usercontrol has all the properties IsChecked, EventId,MethodName ,..., then you can remove the properties from your usercontrol and all works.
but if you wanna create a "real" usercontrol then you should use DependencyProperties and bind them with the right expression within your usercontrol.
btw when you use Binding in WPF then its all about the right DataContext and the right BindingExpression

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.