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Binding From User Control to User Control - Binding Path Error

I am using a UserControl within a UserControl. Everything works except one piece. I get:
BindingExpression path error: 'SelectedItem' property not found on 'object' ''OrganizationDetailsVM' (HashCode=21529561)'. BindingExpression:Path=SelectedItem; DataItem='OrganizationDetailsVM' (HashCode=21529561); target element is 'ExtendedTreeView' (Name='tvApplications'); target property is 'SelectedItem_' (type 'Object')
Here are the relevant bits:
OrganizationDetailsVM.cs
private AdoptionApplication selectedApplication;
public AdoptionApplication SelectedApplication
{
get { return this.selectedApplication; }
set
{
if (this.selectedApplication != value)
{
this.selectedApplication = value;
RaisePropertyChanged("SelectedApplication");
}
}
}
private object selectedTreeItem;
public object SelectedTreeItem
{
get { return this.selectedTreeItem; }
set
{
if (this.selectedTreeItem != value)
{
this.selectedTreeItem = value;
SelectedApplication = selectedTreeItem as AdoptionApplication;
RaisePropertyChanged("SelectedTreeItem");
RaisePropertyChanged("SelectedApplication");
}
}
}
// other stuff
OrganizationDetails.xaml
<uc:ApplicationsControl x:Name="ucApplications" SelectedItem="{Binding SelectedTreeItem}"
AddApplicationCommand="{Binding AddApplicationCommand}"
EditApplicationCommand="{Binding EditApplicationCommand}"
DeleteApplicationCommand="{Binding DeleteApplicationCommand}"/>
ApplicationsControl.xaml
<UserControl x:Class="CareerChanges.Views.UserControls.ApplicationsControl"
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"
xmlns:cc="clr-namespace:CareerChanges"
xmlns:local="clr-namespace:CareerChanges.Views.UserControls"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800">
<UserControl.Resources>
<cc:SimpleFolderConverter x:Key="folderConverter"/>
</UserControl.Resources>
<Grid Background="#FFE5E5E5"
Loaded="Grid_Loaded">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="419*"/>
<ColumnDefinition Width="75*"/>
</Grid.ColumnDefinitions>
<local:ExtendedTreeView x:Name="tvApplications"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"
ItemsSource="{Binding AdoptionApplications}">
<local:ExtendedTreeView.Resources>
<HierarchicalDataTemplate DataType="{x:Type cc:AdoptionApplication}">
<HierarchicalDataTemplate.ItemsSource>
<MultiBinding Converter="{StaticResource folderConverter}" ConverterParameter=", Breeds, FamilyMembers, Persons">
<Binding Path="Organization"/>
<Binding Path="ApplicationPreferences"/>
<Binding Path="FamilyMembers"/>
<Binding Path="ApplicationPersons"/>
</MultiBinding>
</HierarchicalDataTemplate.ItemsSource>
<StackPanel Orientation="Horizontal" Background="Aquamarine">
<TextBlock Text="Application (" />
<TextBlock Text="{Binding Path=ApplicationID}"/>
<TextBlock Text=") "/>
<TextBlock Text="{Binding Path=Title}" FontStyle="Italic"/>
<TextBlock Text=" "/>
<TextBlock Text="{Binding Path=ApplicationDate, StringFormat=dd-MMM-yyyy}"/>
<TextBlock Text=" "/>
<TextBlock Text="{Binding ApplicationStatusID, Converter={StaticResource ApplicationStatusConverter}}"/>
</StackPanel>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type cc:ApplicationPreference}" ItemsSource="{Binding Path=Colours}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding BreedID, Converter={StaticResource BreedConverter}}" />
<TextBlock Text=" [" Foreground="Blue" />
<TextBlock Text="{Binding Colours.Count}" Foreground="Blue" />
<TextBlock Text="]" Foreground="Blue" />
</StackPanel>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type cc:FolderItem}"
ItemsSource="{Binding Path=Items}">
<StackPanel Orientation="Horizontal">
<TextBlock x:Name="txtName" Text="{Binding Path=Name}" />
<TextBlock Text=" [" Foreground="Blue" />
<TextBlock Text="{Binding Items.Count}" Foreground="Blue" />
<TextBlock Text="]" Foreground="Blue" />
</StackPanel>
</HierarchicalDataTemplate>
<DataTemplate DataType="{x:Type cc:Person}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Path=Given}" />
<TextBlock Text=" " />
<TextBlock Text="{Binding Path=Surname}" />
</StackPanel>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:FamilyMemberType}">
<TextBlock Text="{Binding Path=FamilyMemberTypeID, Converter={StaticResource FamilyTypeConverter}}"/>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:ColourPreference}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<StackPanel Grid.Column="0" Orientation="Horizontal">
<TextBlock Text="{Binding ColourID, Converter={StaticResource ColourConverter}}" />
</StackPanel>
<StackPanel Grid.Column="1" Orientation="Horizontal">
<TextBlock Text=" Male: "/>
<CheckBox IsChecked="{Binding Male}" IsEnabled="False"/>
<TextBlock Text=" Female: "/>
<CheckBox IsChecked="{Binding Female}" IsEnabled="False"/>
</StackPanel>
</Grid>
</DataTemplate>
<DataTemplate DataType="{x:Type cc:Organization}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="Organization: " />
<TextBlock Text="{Binding Path=OrganizationName}" />
</StackPanel>
</DataTemplate>
</local:ExtendedTreeView.Resources>
</local:ExtendedTreeView>
<StackPanel Grid.Column="1">
<Button Name="btnAddApplication" Margin="2" Command="{Binding Path=AddApplicationCommand}">Add</Button>
<Button Name="btnEditApplication" Margin="2" Command="{Binding Path=EditApplicationCommand}">Edit</Button>
<Button Name="btnDeleteApplication" Margin="2" Command="{Binding Path=DeleteApplicationCommand}">Delete</Button>
</StackPanel>
</Grid>
</UserControl>
ApplicationsControl.xaml.cs
public object SelectedItem
{
get { return GetValue(SelectedItemProperty); }
set { SetValue(SelectedItemProperty, value); }
}
public static readonly DependencyProperty SelectedItemProperty =
DependencyProperty.Register(
"SelectedItem",
typeof(object),
typeof(ApplicationsControl),
new FrameworkPropertyMetadata(
null, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));
Finally, this is the code for the ExtendedTreeView from this question: Data binding to SelectedItem in a WPF Treeview
ExtendedTreeView.cs
public class ExtendedTreeView : TreeView
{
public ExtendedTreeView()
: base()
{
this.SelectedItemChanged += new RoutedPropertyChangedEventHandler<object>(___ICH);
}
void ___ICH(object sender, RoutedPropertyChangedEventArgs<object> e)
{
if (SelectedItem != null)
{
SetValue(SelectedItem_Property, SelectedItem);
}
}
public object SelectedItem_
{
get { return (object)GetValue(SelectedItem_Property); }
set { SetValue(SelectedItem_Property, value); }
}
public static readonly DependencyProperty SelectedItem_Property = DependencyProperty.Register("SelectedItem_", typeof(object), typeof(ExtendedTreeView), new UIPropertyMetadata(null));
}
For some reason, the binding isn't making it from OrganizationDetailsVM, through OrganizationDetails.xaml to ApplicationsControl.xaml and down to ExtendedTreeview. All the other bindings work perfectly. The tree view does what it should, except for binding to the selected item.
To sum up, I'm having a problem getting from here:
<uc:ApplicationsControl x:Name="ucApplications" SelectedItem="{Binding SelectedTreeItem}"
AddApplicationCommand="{Binding AddApplicationCommand}"
EditApplicationCommand="{Binding EditApplicationCommand}"
DeleteApplicationCommand="{Binding DeleteApplicationCommand}"/>
... to here:
<local:ExtendedTreeView x:Name="tvApplications"
HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"
ItemsSource="{Binding AdoptionApplications}">
It boils down to this binding not working:
SelectedItem_="{Binding Path=SelectedItem, Mode=TwoWay, ValidatesOnNotifyDataErrors=True}"

Found it! I'm still new at data binding. After looking at some other code, I modified the binding to:
SelectedItem="{Binding Path=SelectedItem, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:DogPersonsControl}}}">

Could not pass values from view to viewmodel through commands

I am implementing MVVM pattern for my application. I have my Views, ViewModel, Model and Commands and Converters being implemented. Now I am not able to pass my textboxes values from my datatemplate to my ViewModel through the command binding. I am able to click on the button to attempt the update process but its not able to pass the textboxes value. Are there something i need to change on my command class?
Here is my XAML:
<DataGrid AutoGenerateColumns="False" Grid.Row="2" Grid.ColumnSpan="4" Grid.RowSpan="3" x:Name="productionLineConfigDataGrid" Margin="70,0.2,70,0" ItemsSource="{Binding listAllProductionLineConfigs}">
<DataTemplate>
<StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="12" Text="ID: " VerticalAlignment="Center" />
<TextBlock x:Name="txtBlockLineId" FontSize="16" Foreground="MidnightBlue" Text="{Binding ProductionLineId, Mode=TwoWay}" VerticalAlignment="Center" />
</StackPanel>
<StackPanel>
<Button x:Name="btnUpdate" Content="Update" VerticalAlignment="Center" HorizontalAlignment="Right" Click="btnUpdate_Click" Command="{Binding DataContext.updateProductionLineConfigCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:production_line_config_home}}}" CommandParameter="{Binding ProductionLineConfig}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</DataGrid>
Here is the method from my ViewModel:
public ProductionLineConfig ProductionLineConfig
{
get { return productionlineconfig; }
set
{
productionlineconfig = value;
OnPropertyChanged("ProductionLineConfig");
}
}
This is the error message i am getting:
System.Windows.Data Error: 40 : BindingExpression path error: 'ProductionLineConfig' property not found on 'object' ''ProductionLineConfig' (HashCode=47309994)'. BindingExpression:Path=ProductionLineConfig; DataItem='ProductionLineConfig' (HashCode=47309994); target element is 'Button' (Name=''); target property is 'CommandParameter' (type 'Object')
I have included the image for my application here
This is the entire xaml code here and this is the entire viewmodel code here

I'm only going to take a guess at this.
Assuming ProductionLineConfig is what you are binding to for ProductionLineId in the template. Then you probably are just wanting to pass your binding source as the command parameter
CommandParameter="{Binding}"
When {Binding} is empty, it means the Binding is bound to whatever Source there is. Which is also just shorthand for...
{Binding DataContext,RelativeSource={RelativeSource Self}}.
In turn (if the stars align), then it should be your ProductionLineConfig

Based on your code source, I made a sample implementation, to achieve your requirement.
Sample VM:
using System;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using System.Windows;
namespace WpfApp5.ViewModels
{
public class ProductionLineConfigViewModel : INotifyPropertyChanged
{
public CustomCommand<ProductionLineConfig> UpdateCommand { get; }
public ProductionLineConfigViewModel()
{
PopulateProductionLineConfigs();
UpdateCommand = new CustomCommand<ProductionLineConfig>(UpdateConfig, (u) => true);
}
private ObservableCollection<ProductionLineConfig> _listAllProductionLineConfigs;
public ObservableCollection<ProductionLineConfig> listAllProductionLineConfigs
{
get { return _listAllProductionLineConfigs; }
set
{
_listAllProductionLineConfigs = value;
OnPropertyChanged();
}
}
// Call this from constructor.
private void PopulateProductionLineConfigs()
{
listAllProductionLineConfigs = new ObservableCollection<ProductionLineConfig>
{
new ProductionLineConfig
{
ProductionLineId = 1,
ProductionLineCode = "001",
ProductionLineCreatedDate = DateTime.Today.Date,
ProductionLineName = "safdsf",
ProductionLineStatus = true
},
new ProductionLineConfig
{
ProductionLineId = 1,
ProductionLineCode = "002",
ProductionLineCreatedDate = DateTime.Today.Date,
ProductionLineName = "sadfadfsdf",
ProductionLineStatus = true
}
};
}
private void UpdateConfig(ProductionLineConfig config)
{
MessageBox.Show("Line Name update: " + config.ProductionLineName);
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
public class ProductionLineConfig
{
public int ProductionLineId { get; set; }
public string ProductionLineCode { get; set; }
public string ProductionLineName { get; set; }
public bool ProductionLineStatus { get; set; }
public DateTime ProductionLineCreatedDate { get; set; }
}
}
Sample XAML:
<Window x:Name="Root" x:Class="WpfApp5.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:viewModels="clr-namespace:WpfApp5.ViewModels"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Window.DataContext>
<viewModels:ProductionLineConfigViewModel/>
</Window.DataContext>
<Grid Background="#FF006E8C">
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition/>
<ColumnDefinition/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<Label Grid.ColumnSpan="4" Content="KAD ShopFloor System" HorizontalAlignment="Center" Margin="10" FontWeight="Bold" FontSize="30" FontFamily="Segoe UI" Foreground="White"/>
<Separator Grid.ColumnSpan="4" Grid.RowSpan="3" Background="White" Margin="0,-35,-0.4,39.2"/>
<DataGrid AutoGenerateColumns="False" Grid.Row="2" Grid.ColumnSpan="4" Grid.RowSpan="3" x:Name="productionLineConfigDataGrid" Margin="70,0.2,70,0"
ItemsSource="{Binding DataContext.listAllProductionLineConfigs, ElementName=Root}">
<DataGrid.Columns>
<DataGridTextColumn Header="ID" Binding="{Binding ProductionLineId, Mode=TwoWay}"/>
<DataGridTextColumn Header="Production Line Code" Binding="{Binding ProductionLineCode, Mode=TwoWay}"/>
<DataGridTextColumn Header="Production Line Name" Binding="{Binding ProductionLineName, Mode=TwoWay}"/>
<DataGridTextColumn Header="Status" Binding="{Binding ProductionLineStatus, Mode=TwoWay}"/>
<DataGridTextColumn Header="Created Date" Binding="{Binding ProductionLineCreatedDate, Mode=TwoWay}"/>
</DataGrid.Columns>
<DataGrid.RowDetailsTemplate>
<DataTemplate>
<Border BorderThickness="0" Background="BlanchedAlmond" Padding="10">
<StackPanel Orientation="Vertical" x:Name="stck">
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="12" Text="ID: " VerticalAlignment="Center" />
<TextBlock x:Name="txtBlockLineId" FontSize="16" Foreground="MidnightBlue" Text="{Binding ProductionLineId, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="12" Text="Line Code: " VerticalAlignment="Center" />
<TextBlock x:Name="txtBlockLineCode" FontSize="16" Foreground="MidnightBlue" Text="{Binding ProductionLineCode, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<TextBlock FontSize="12" Text="Line Name: " VerticalAlignment="Center" />
<TextBox x:Name="txtLineName" FontSize="16" Foreground="MidnightBlue" Text="{Binding ProductionLineName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" VerticalAlignment="Center" />
</StackPanel>
<!--<StackPanel Orientation="Horizontal">
<TextBlock FontSize="12" Text="Status: " VerticalAlignment="Center" />
<ComboBox ItemsSource="{Binding RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type DataGrid}},
Path=DataContext.Statusstring}" SelectedValue="{Binding ProductionLineStatus, Converter={StaticResource statusToBooleanConverter}, Mode=TwoWay}" x:Name="cbProductionLineStatus" FlowDirection="LeftToRight" FontSize="16" Foreground="MidnightBlue"
HorizontalAlignment="Stretch" VerticalAlignment="Center"/>
</StackPanel>-->
<StackPanel>
<Button x:Name="btnUpdate" Content="Update" VerticalAlignment="Center" HorizontalAlignment="Right"
Command="{Binding DataContext.UpdateCommand, ElementName=Root}"
CommandParameter="{Binding}" />
</StackPanel>
</StackPanel>
</Border>
</DataTemplate>
</DataGrid.RowDetailsTemplate>
</DataGrid>
</Grid>
</Window>
Sample output:
Key changes here,
You need to change your list to observable collection
Create a custom command that accepts an object, see this post: [UWP/MVVM]Enable/Disable Button in RadDataGrid Data Template Column that have commands bound to them upon conditions
Command Parameter should be the iterated item, can be achieve by CommandParameter={Binding}
In you two way bindings, make sure to add UpdateSourceTrigger=PropertyChanged

Databinding a user control within an itemscontrol

I have a UserControl that has a ViewModel containing an instance of my own custom class, call it Person. This ViewModel is set as the DataContext of the control. I am wanting to use this control in my main window which has, in its ViewModel a List of type Person called People. I am calling the control in my xaml like this:
<ItemsControl ItemsSource="{Binding People}">
<ItemsControl.ItemsTemplate>
<DataTemplate>
<userControls:PersonDetails />
</DataTemplate>
</ItemsControl.ItemsTemplate>
</ItemsControl>
Properties within the control are bound in this manner.
<TextBlock Text="{Binding Person.Name}" />
When I run I am getting the correct number of Controls for the amount of People in the list but no details are populated. I know I am doing something simple wrong but can't find it. Please help.
EDIT:
My UserControl xaml looks like this:
<UserControl x:Class="AddressBook.UserControls.PersonDetails"
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"
xmlns:local="clr-namespace:AddressBook.UserControls"
xmlns:vm="clr-namespace:AddressBook.ViewModels"
xmlns:enums="clr-namespace:AddressBook.Models"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="1000">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="40" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="1*" />
</Grid.ColumnDefinitions>
<TextBlock Style="{StaticResource PersonDetailHeader}" Text="Person Name:" />
<TextBlock Style="{StaticResource PersonDetailValue}" Grid.Column="1" Text="{Binding Person.Name,
UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Style="{StaticResource PersonDetailHeader}" VerticalAlignment="Center" Grid.Row="1" Text="Street Address:" />
<TextBlock Style="{StaticResource PersonDetailValue}" Grid.Row="1" Grid.Column="1"
Text="{Binding Person.StreetAddress, UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Style="{StaticResource PersonDetailHeader}" Grid.Row="2" Text="Town:" />
<TextBlock Style="{StaticResource PeronDetailValue}" Grid.Row="2" Grid.Column="1"
Text="{Binding Person.Town, UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Style="{StaticResource PersonDetailHeader}" Grid.Row="3" Text="County:" />
<TextBlock Style="{StaticResource PersonDetailValue}" Grid.Row="3" Grid.Column="1"
Text="{Binding Person.County, UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Style="{StaticResource PersonDetailHeader}" Grid.Row="4" Text="Postcode:" />
<TextBlock Style="{StaticResource PersonDetailValue}" Grid.Row="4" Grid.Column="1"
Text="{Binding Person.Postcode, UpdateSourceTrigger=PropertyChanged}" />
<TextBlock Style="{StaticResource PersonDetailHeader}" Grid.Row="5" Text="Phone:" />
<TextBlock Style="{StaticResource PersonDetailValue}" Grid.Row="5" Grid.Column="1"
Text="{Binding Person.Phone, UpdateSourceTrigger=PropertyChanged}" />
<StackPanel Grid.Row="7" Grid.ColumnSpan="2" HorizontalAlignment="Center" Orientation="Horizontal">
<Button Style="{StaticResource ButtonStyle}" Content="Click" Command="{Binding ButtonClickCommand}" />
</StackPanel>
</Grid>
UserControl ViewModel:
public class PersonDetailsViewModel
{
public Person Person { get; set; }
public Command ButtonClickCommand { get; }
public PersonDetailsViewModel()
{
ButtonClickCommand = new Command(ButtonClick);
}
private void ButtonClick(object obj)
{
throw new NotImplementedException();
}
UserControl.xaml.cs:
public partial class PersonDetails : UserControl
{
public PersonDetails()
{
InitializeComponent();
}
}
Person.cs
public class Person : BaseModel
{
public string Name
{
get { return name; }
set
{
name = value;
NotifyPropertyChanged();
}
etc....
MainViewModel:
public class MainViewModel : BaseViewModel
{
public ObservableCollection<Person> People { get; }
= new ObservableCollection<Person>();
public MainViewModel()
{
PopulatePeople();
}
}

Now I understand why you were creating the PersonDetailsViewModel in the UserControl XAML, and what the problem was with the command.
The simplest way to fix this is to make MainViewModel.People a collection of PersonDetailsViewModel instead of Person. That's what I'd do.
But if you want to leave MainViewModel.People as it is, while still using PersonDetailsViewModel inside your UserControl, that makes sense to me. You could do this:
.xaml
<UserControl
x:Class="AddressBook.UserControls.PersonDetails"
DataContextChanged="PersonDetails_DataContextChanged"
...etc...
>
<!-- Give the Grid a name... -->
<Grid x:Name="OuterGrid">
.xaml.cs
public PersonDetails()
{
InitializeComponent();
}
private void PersonDetails_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
{
// ...so we can give the Grid a different DataContext
OuterGrid.DataContext = new PersonDetailsViewModel {
Person = (Person)this.DataContext
};
}
Now it will inherit a Person for its DataContext, but internally it will use a PersonDetailsViewModel based on that Person.

Not sure if that's what you are trying to do.
If you only wish to display some carac of every Person present in your People List you could do :
<Grid>
<ItemsControl ItemsSource="{Binding People}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Margin="0,0,0,5">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="100" />
</Grid.ColumnDefinitions>
<TextBlock Text="{Binding Name}" />
<TextBlock Grid.Column="1" Text="{Binding Age}" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
That will bind you Text on the Name property of each element of your list, so on the name of each Person of your list.
As your ItemsSource is already bound to People, the Binding of your Items is already on each Person of your List, so you should call your properties directly as {Binding Name} and not {Binding Person.Name}

change booleanToVisibilityConverter from code behind - wpf c #

<Page.Resources>
<ResourceDictionary>
<BooleanToVisibilityConverter x:Key="booleanToVisibilityConverter" x:Name="testTest" />
</ResourceDictionary>
</Page.Resources>
itemscontrol:
<Grid Grid.Row="1" Grid.ColumnSpan="2" Name="testName">
<ScrollViewer VerticalScrollBarVisibility="Hidden" PanningMode="Both">
<ItemsControl ItemsSource="{Binding Path=NextMeetingList}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Grid.Column="0" Grid.Row="0">
<Border x:Name = "myVariable" Grid.Column="0" Grid.Row="0" Margin="10" Height="30" Background="#A2C2E7" CornerRadius="5" BorderBrush="#A2C2E7">
<Grid Margin="8,0,8,0" Background="#A2C2E7">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"></ColumnDefinition>
<ColumnDefinition Width="1*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="30"/>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0" Foreground="White" FontWeight="Bold" FontSize="15" Margin="0,4,0,0" HorizontalAlignment="Left">month</TextBlock>
<TextBlock Grid.Row="0" Grid.Column="1" Foreground="White" FontWeight="Bold" FontSize="15" Margin="0,4,0,0" HorizontalAlignment="Right">1 Meeting</TextBlock>
</Grid>
</Border>
<Border Grid.Column="0" Grid.Row="0" Margin="10" Height="60" Background="GhostWhite" CornerRadius="3" BorderBrush="{Binding BorderColor}" BorderThickness="0,8,0,0">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="118"></ColumnDefinition>
<ColumnDefinition Width="*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="60"/>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0" HorizontalAlignment="Left" FontSize="40" Margin="10,5,0,0" Style="{DynamicResource Lato-Semibold}" Text="{Binding endDate.Day}"/>
<TextBlock Grid.Row="0" Grid.Column="0" HorizontalAlignment="Left" FontSize="12" Margin="77,13,0,0" Height="Auto" Style="{DynamicResource Lato-Semibold}" Text="{Binding DayString}"/>
<TextBlock Grid.Row="0" Grid.Column="0" HorizontalAlignment="Left" FontSize="14" Margin="70,26,0,0" Height="Auto" Style="{DynamicResource Lato-Semibold}" Text="{Binding endDate.Hour}"/>
<TextBlock Grid.Row="0" Grid.Column="0" HorizontalAlignment="Left" FontSize="14" Margin="86,26,0,0" Height="Auto" Style="{DynamicResource Lato-Semibold}" Text=":"/>
<TextBlock Grid.Row="0" Grid.Column="0" HorizontalAlignment="Left" FontSize="14" Margin="90,26,0,0" Height="Auto" Style="{DynamicResource Lato-Semibold}" Text="{Binding MinuteString}"/>
<Border Grid.Row="0" Grid.Column="0" Width="1" BorderBrush="#BABABA" Height="40" Margin="115,-6,0,0" BorderThickness="1" HorizontalAlignment="Left"></Border>
<TextBlock Grid.Row="0" Grid.Column="1" HorizontalAlignment="Left" Text="{Binding subject}" FontWeight="Bold" FontSize="17" Margin="10,10,0,0"/>
<TextBlock Grid.Row="0" Grid.Column="1" Width="Auto" TextWrapping="Wrap" HorizontalAlignment="Left" Text="{Binding descr}" FontSize="10" Margin="20,27,150,0"/>
<TextBlock Grid.Row="0" Grid.Column="1" HorizontalAlignment="Right" Text="{Binding companyName}" FontSize="10" Margin="0,10,30,0"/>
<TextBlock Grid.Row="0" Grid.Column="1" HorizontalAlignment="Right" Text="sala del consiglio" FontSize="10" Margin="0,27,30,0"/>
<TextBlock Grid.Row="0" Grid.Column="1" HorizontalAlignment="Right" Text=">" FontSize="15" VerticalAlignment="Center" Margin="0,-5,10,0"/>
</Grid>
</Border>
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</ScrollViewer>
</Grid>
Hello everyone , I should be able to make a grid Collapsed inside a ItemsControl in WPF .
The problem is that I can not understand how to use the booleanToVisibilityConverter from code behind .
Maybe I'm missing out on a glass of water but I can not connect how to do, if the name TestTest septum can not see it then the code-behind .
from code behind i don't see "myVariable"

To get hold of the converter from code-behind, you'd have to look it up in the Page's Resources dictionary. Do something like this in your Page class:
IValueConverter converter = this.Resources["booleanToVisibilityConverter"] as IValueConverter;
Giving the converter's resource entry a Name is not necessary; here you want to use the Key. Also, converters are normally used with XAML bindings -- if you want one in code, you can just instantiate one:
IValueConverter converter = new BooleanToVisibilityConverter();
Common usage goes something like this:
<Window.Resources>
<ResourceDictionary>
<BooleanToVisibilityConverter x:Key="Converter" />
</ResourceDictionary>
</Window.Resources>
<Grid Visibility="{Binding Display, Converter={StaticResource Converter}}">
...
</Grid>
Code-behind, using the window class itself as the data context:
public partial class MainWindow
{
public bool Display { get; set; };
public MainWindow()
{
InitializeComponent();
DataContext = this; // For the binding
Display = true;
}
}
Okay, one more, this time without data binding or converter:
<Grid x:Name="myGrid">
...
</Grid>
Code-behind:
public partial class MainWindow
{
public MainWindow()
{
InitializeComponent();
myGrid.Visibility = Visibility.Visible;
}
}
The above doesn't explain why the OP couldn't reference "myVariable" from code-behind. That's because it's in a template, which is instantiated (dynamically) once per item in the collection.
It's still possible to get at it from code -- dynamically. For example, this XAML uses a DataTemplate:
<ItemsControl ItemsSource="{Binding Names}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid>
<Grid x:Name="innerGrid" Loaded="OnGridLoaded" DataContext="{Binding Name, Mode=OneWay}">
<TextBox Text="{Binding Path=., Mode=OneWay}" />
</Grid>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
The following code-behind lets us reach into the template and make "innerGrid" disappear selectively:
public class Data
{
public string Name { get; }
public Data(string name)
{
Name = name;
}
}
public partial class MainWindow
{
public Data[] Names { get; } = { new Data("Hello"), new Data("World") };
public MainWindow()
{
InitializeComponent();
DataContext = this;
}
private void OnGridLoaded(object sender, RoutedEventArgs e)
{
Grid outerGrid = sender as Grid;
Grid innerGrid = outerGrid?.FindName("innerGrid") as Grid;
if (innerGrid != null)
{
string name = innerGrid.DataContext as string;
if (name == "Hello")
{
innerGrid.Visibility = Visibility.Collapsed;
}
}
}
}
(To make the string easily accessible I bound the Data object to the "innerGrid" DataContext.)

How to set tooltip with many rows for each (dynamic) listbox item in Silverlight

I would like to set in Silverlight for each item in a ListBox a tooltip with many rows.
In XAML i have a listbox and a button:
<ListBox Height="100" HorizontalAlignment="Left" Margin="24,136,0,0" Name="listBox1" VerticalAlignment="Top" Width="109" ItemsSource="{Binding}">
<Button Content="Add" Name="button_add" VerticalAlignment="Top" Width="118" Click="add_Click">
in c#
private void button_add_Click(object sender, RoutedEventArgs e)
{
ObservableCollection<Person> obs1 = new ObservableCollection<Person>();
obs1.Add(new Person(){Name="Name1", Age=1});
obs1.Add(new Person(){Name="Name2", Age=2});
listBox1.ItemsSource = obs1;
// This Line of Code MUST NOT BE USED!! listBox1.DisplayMemberPath = "Name";
}
public class Person
{
public String Name { get; set; }
public int Age { get; set; }
public override string ToString()
{
return Name;
}
}
I would like to show for each item the Age as my tooltip.
Edit: Ok, this is the Solution for showing only AGE as tooltip. That is one Line/Row.
<ListBox Height="100" HorizontalAlignment="Left" Margin="24,136,0,0" Name="listBox1" VerticalAlignment="Top" Width="109" ItemsSource="{Binding}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}" ToolTipService.ToolTip="{Binding Age}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
But what if i want to show a Tooltip with 2 Lines? something like:
Name: Name1
Age: 1
Edit: 3 rows, 2 columns. i also added public String Comment { set; get; } to class Person
<ListBox Height="100" HorizontalAlignment="Left" Margin="24,136,0,0" Name="listBox1" VerticalAlignment="Top" Width="109" ItemsSource="{Binding}">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<ToolTipService.ToolTip>
<ToolTip>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="40"></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="80"/>
<ColumnDefinition Width="250"/>
</Grid.ColumnDefinitions>
<TextBlock Text="Name: " Grid.Row="0" Grid.Column="0" />
<TextBlock Text="{Binding Name}" Grid.Row="0" Grid.Column="1"/>
<TextBlock Text="Age: " Grid.Row="1" Grid.Column="0"/>
<TextBlock Text="{Binding Age}" Grid.Row="1" Grid.Column="1"/>
<TextBlock Text="Comment: " Grid.Row="2" Grid.Column="0"/>
<TextBlock Text="{Binding Comment}" Grid.Row="2" Grid.Column="1" TextWrapping="Wrap" />
</Grid>
</ToolTip>
</ToolTipService.ToolTip>
<TextBlock Text="{Binding Name}" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
But there is stil a problem. The comment can be short or long, so i would like to make the ROWS/LINES/SPACE for Comment to be variable or else Text is cut off.

You can use any controls for tooltip content:
<ToolTipService.ToolTip>
<StackPanel Orientation="Vertical">
<TextBlock Text="{Binding Name}" />
<TextBlock Text="{Binding Age}" />
</StackPanel>
</ToolTipService.ToolTip>
Other possibility would be to use a converter, that returns the Name and Age separated by \r\n.