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Binding parameter to a nested ListView using SelectedItem

I'm pretty new to coding in c# and I'm trying on a wpf app to transfer data between different folders.
To visualize the folders and subfolders I've got a tabcontrol with different mainfolders, and under each tab a ListView with information on the subfolders.
All data is gathered in a BindingList 'Klinieken', which is filled with objects 'Kliniek' (mainfolders) which contains objects 'Patient' (subfolders) which is filled with information about said folder. Here is the .xaml file for the mainwindow:
<Grid x:Name="LayoutRoot" Background="#555555">
<Grid.RowDefinitions>
<RowDefinition Height="420" />
<RowDefinition Height="116" />
</Grid.RowDefinitions>
<Grid x:Name="KliniekTabs" Background="#555555" Grid.Row="0" Margin="10 10 10 10">
<TabControl ItemsSource="{Binding Klinieken}"
SelectedItem="{Binding BronKliniek}"
TabStripPlacement="Top">
<TabControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding KliniekNaam}" />
</DataTemplate>
</TabControl.ItemTemplate>
<TabControl.ContentTemplate>
<DataTemplate>
<ListView ItemsSource="{Binding Path=Patienten}"
SelectedItem="{Binding Path=SelectedPatient}">
<ListView.Resources>
<Style TargetType="{x:Type GridViewColumnHeader}">
<Setter Property="HorizontalContentAlignment" Value="Left"/>
</Style>
</ListView.Resources>
<ListView.View>
<GridView>
<GridViewColumn Header="Patientnaam"
Width="250"
DisplayMemberBinding="{Binding PatientNaam}"/>
<GridViewColumn Header="Zisnr"
Width="250"
DisplayMemberBinding="{Binding PatientZis}"/>
<GridViewColumn Header="Aanmaakdatum"
Width="250"
DisplayMemberBinding="{Binding AanmaakDatum}"/>
</GridView>
</ListView.View>
</ListView>
</DataTemplate>
</TabControl.ContentTemplate>
</TabControl>
</Grid>
<Grid x:Name="WindowControls" Background="#777777" Grid.Row="1" Margin="100 5 100 10">
<StackPanel Orientation="Vertical">
<Label Margin="-80 0 0 0" HorizontalAlignment="Center">Doel kliniek</Label>
<ComboBox ItemsSource="{Binding Path=Klinieken}"
x:Name="doelKliniekDD"
SelectedItem="{Binding DoelKliniek}"
Margin="-120 0 0 0"
HorizontalAlignment="Center">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=KliniekNaam}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<StackPanel Orientation="Horizontal" Margin="20 0 0 0" Height="50" VerticalAlignment="Bottom" HorizontalAlignment="Center">
<Button Height="25" Style="{StaticResource Button_Orange}" Command="{Binding TransferButtonCommand}" CommandParameter="{Binding ElementName=window, Mode=OneWay}" Margin="0 0 10 0">Transfer</Button>
<Button Height="25" Style="{StaticResource Button_Orange}" Command="{Binding CopyButtonCommand}" CommandParameter="{Binding ElementName=window, Mode=OneWay}" Margin="10 0 20 0">Kopieer</Button>
<Button Height="25" Style="{StaticResource Button_Grey}" Command="{Binding CloseCommand}" CommandParameter="{Binding ElementName=window, Mode=OneWay}" Margin="20 0 0 0">Cancel</Button>
</StackPanel>
</StackPanel>
</Grid>
</Grid>
And here is the MainViewModel that is referenced in the .xaml:
//attributen
string monacoDirectory;
List<string> aanwezigeClinics;
Installation installation;
//constructor
public MainViewModel()
{
monacoDirectory = ConfigurationManager.AppSettings["monacoDirectory"];
aanwezigeClinics = new List<string>(Directory.GetDirectories(monacoDirectory, "*", SearchOption.TopDirectoryOnly));
aanwezigeClinics.Remove(monacoDirectory + #"\defaults");
aanwezigeClinics.Remove(monacoDirectory + #"\physics");
installation = new Installation(aanwezigeClinics);
Klinieken = new BindingList<Kliniek>();
foreach (var kliniek in installation.Klinieken)
{
Klinieken.Add(kliniek);
}
}
private Kliniek _doelKliniek;
private Kliniek _bronKliniek;
private Patient _selectedPatient;
private BindingList<Kliniek> _klinieken = new BindingList<Kliniek>();
public BindingList<Kliniek> Klinieken
{
get { return _klinieken; }
set { _klinieken = value; }
}
public Kliniek DoelKliniek
{
get { return _doelKliniek; }
set
{
_doelKliniek = value;
OnPropertyChanged();
}
}
public Kliniek BronKliniek
{
get { return _bronKliniek; }
set
{
_bronKliniek = value;
OnPropertyChanged();
}
}
public Patient SelectedPatient
{
get { return _selectedPatient; }
set
{
_selectedPatient = value;
MessageBox.Show("hoi");
OnPropertyChanged();
}
}
The data shows up in the gui just fine, which i was quite happy with. And using SelectedItem on the TabControl and the ComboBox i use later worked out beautifully aswell, but I just cant seem to get the SelectedItem on the ListView to work. I have added a button to test the output of the fields and SelectedPatient always returns as null.
If i check the 'Live Visual Tree' in VS and go to the properties of the ListView i can see the Patient as SelectedItem, so that tells me its not a selection but a binding problem. Furthermore ive tried to google for nested bindings, but the suggestions there didnt change anything about my situation.
Is a nested binding like this possible, or should i take a whole different approach?

Had a similar problem quite a while ago. The suggestions below solved it for me at the time.
Use SelectedValue instead of SelectedItem. This is because SelectedItem doesn't change until the control has been validated. SelectedValue changes whenever the user selects an item. The code you could use is as follows:
SelectedValue="{Binding BronKliniek, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
For the button part, try to provide CommandParameter="{Binding}" instead of CommandParameter="{Binding ElementName=window, Mode=OneWay}". This way, you'll get the value of the current DataContext of the button, which you can then use to extract the data you want from this DataContext.

Issue binding grouped data to cvs for semantic zoom

I'm having some trouble getting my semantic zoom bind correctly to my CollectionViewSource. I'm pretty new to MVVM, so I'm not sure i have stuff setup correctly.
View Model
private async void GetData()
{
// Simulate pulling data from api
string response;
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(new Uri(#"ms-appx:///DesignData/GetLive.json"));
using (StreamReader sRead = new StreamReader(await file.OpenStreamForReadAsync()))
response = await sRead.ReadToEndAsync();
// Deserialize data to class
LiveStreamModel liveGames = JsonConvert.DeserializeObject<LiveStreamModel>(response);
Schedules = liveGames.schedule;
// Group data by event
var groupData = liveGames.schedule.GroupBy(a => a.#event);
// Set cvs source to grouped data
ScheduleSource = new CollectionViewSource() { IsSourceGrouped = true, Source = groupData };
}
private CollectionViewSource scheduleSource;
public CollectionViewSource ScheduleSource
{
get
{
return scheduleSource;
}
set
{
scheduleSource = value;
RaisePropertyChanged("ScheduleSource");
}
}
View
Page.Resources>
<DataTemplate x:Key="ZoomedInTemplate">
<StackPanel Orientation="Horizontal" MinWidth="200" Margin="12,6,0,6">
<!--<Image Source="{Binding ImagePath}" Height="80" Width="80"/>-->
<StackPanel Margin="20,0,0,0">
<TextBlock Text="{Binding homeTeam}" Style="{StaticResource BaseTextBlockStyle}"/>
<TextBlock Text="{Binding awayTeam}" TextWrapping="Wrap" HorizontalAlignment="Left" Width="300"
Style="{StaticResource BodyTextBlockStyle}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="ZoomedInGroupHeaderTemplate">
<TextBlock Text="{Binding event}" Foreground="{ThemeResource ApplicationForegroundThemeBrush}"
Style="{StaticResource SubtitleTextBlockStyle}"/>
</DataTemplate>
<DataTemplate x:Key="ZoomedOutTemplate">
<TextBlock Text="{Binding event}" Style="{StaticResource SubtitleTextBlockStyle}"/>
</DataTemplate>
</Page.Resources>
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<SemanticZoom x:Name="GetLiveZoom" >
<SemanticZoom.ZoomedInView>
<GridView x:Name="GetLiveGrid" ItemsSource="{Binding ScheduleSource.View}" ItemTemplate="{StaticResource ZoomedInTemplate}" SelectionMode="Single"
ScrollViewer.IsHorizontalScrollChainingEnabled="False">
<GridView.GroupStyle>
<GroupStyle HeaderTemplate="{StaticResource ZoomedInGroupHeaderTemplate}" />
</GridView.GroupStyle>
</GridView>
</SemanticZoom.ZoomedInView>
<SemanticZoom.ZoomedOutView>
<GridView x:Name="GetLiveList" ItemsSource="{Binding ScheduleSource.View.CollectionGroups}" ItemTemplate="{StaticResource ZoomedOutTemplate}" SelectionMode="None"
ScrollViewer.IsVerticalScrollChainingEnabled="False"/>
</SemanticZoom.ZoomedOutView>
</SemanticZoom>
</Grid>
When debugging, my data is getting grouped properly by #event, but setting the source of the cvs to the grouped data and binding that to the semantic zoom control results in nothing showing up.

You need to fix the following data binding:
1) For ZoomedInGroupHeaderTemplate, because the Source is grouped data, so if you want to show the group name in ZoomedInView, set data binding for Key property:
<DataTemplate x:Key="ZoomedInGroupHeaderTemplate">
<TextBlock Text="{Binding Key}" Foreground="{ThemeResource ApplicationForegroundThemeBrush}"
Style="{StaticResource SubtitleTextBlockStyle}"/>
</DataTemplate>
2) For ZoomedOutTemplate, the Source is ICollectionView.CollectionGroups, ref MSDN -> ICollectionViewGroup interface
We need to use ICollectionViewGroup.Group property to get group name in ZoomedOutView:
<DataTemplate x:Key="ZoomedOutTemplate">
<TextBlock Text="{Binding Group.Key}" Style="{StaticResource SubtitleTextBlockStyle}"/>
</DataTemplate>
Check my completed sample in Github
Screenshot for ZoomedInView:
Screenshot for ZoomedOutView:

BindingExpression Path Error - How to structure code in MVVM model?

I have a Button that when clicked should adjust the Widths of two Grids.
<DataTemplate x:Key="ItemTemplate">
<DockPanel Width="Auto">
<Button Click="SelectMovie_Click" DockPanel.Dock="Top">
<Button.Template>
<ControlTemplate >
<Image Source="{Binding image}"/>
</ControlTemplate>
</Button.Template>
<i:Interaction.Behaviors>
<local:UniqueNameBehavior ID="{Binding id}"/>
</i:Interaction.Behaviors>
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseLeftButtonDown">
<i:InvokeCommandAction Command="{Binding ShowRightGridCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
<TextBlock Text="{Binding title}" HorizontalAlignment="Center" DockPanel.Dock="Bottom"/>
</DockPanel>
</DataTemplate>
This Button is displayed within a Grid as such:
<Grid Grid.Row="2" >
<Grid.ColumnDefinitions>
<ColumnDefinition Width="{Binding LeftGridWidth}" />
<ColumnDefinition Width="{Binding RightGridWidth}" />
</Grid.ColumnDefinitions>
// BUTTONS DISPLAYED HERE
<Grid x:Name="LeftGrid" Grid.Row="2" Grid.Column="0" >
<Border BorderThickness="1" BorderBrush="Red">
<ItemsControl ItemTemplate="{StaticResource ItemTemplate}" ItemsSource="{Binding _movies}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="5" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
</Border>
</Grid>
<Grid x:Name="RightGrid" HorizontalAlignment="Left" Grid.Row="2" Grid.Column="1" >
<DockPanel>
<StackPanel VerticalAlignment="Top" Height="200">
<TextBlock Width="200" Height="50" DockPanel.Dock="Top" HorizontalAlignment="Left">
<TextBlock.Text>
<MultiBinding StringFormat="{}{0} ({1})">
<Binding Path = "SelectedMovie.title"/>
<Binding Path = "SelectedMovie.year"/>
</MultiBinding>
</TextBlock.Text>
</TextBlock>
</StackPanel>
<StackPanel VerticalAlignment="Top" Height="200">
<Grid HorizontalAlignment="Center">
<Image Source="star_icon.png" Width="100" Height="100" VerticalAlignment="Top"/>
<TextBlock Text="{Binding SelectedMovie.rating}" Style="{StaticResource AnnotationStyle}" Width="150"/>
</Grid>
</StackPanel>
</DockPanel>
</Grid>
</Grid>
ViewModel
public List<MediaDetail> _movies { get; set; }
public string selectedMovieID { get; set; }
private GridLength _leftGridWidth;
private GridLength _rightGridWidth;
private readonly GridLength _defaultRightGridWidth = new GridLength(0, GridUnitType.Pixel);
public MoviePanelViewModel()
{
ShowRightGridCommand = new DelegateCommand(SwitchRightGridWidth);
LeftGridWidth = new GridLength(7, GridUnitType.Star);
RightGridWidth = _defaultRightGridWidth;
}
private void SwitchRightGridWidth()
{
RightGridWidth = RightGridWidth == _defaultRightGridWidth ? new GridLength(3, GridUnitType.Star) : _defaultRightGridWidth;
}
public GridLength LeftGridWidth
{
get { return _leftGridWidth; }
set { _leftGridWidth = value; OnPropertyChanged("LeftGridWidth"); }
}
public GridLength RightGridWidth
{
get { return _rightGridWidth; }
set { _rightGridWidth = value; OnPropertyChanged("RightGridWidth"); }
}
public ICommand ShowRightGridCommand { get; set; }
The problem is that when I run my code, I get the error:
BindingExpression path error: 'ShowRightGridCommand' property not found on 'object' ''MediaDetail'
I am not sure how to structure my code such that the Width properties for the Grids can remain in the ViewModel but the Trigger for my Button also works. The DataContext for my View is the ViewModel.
Is there a good way to achieve this?
Thank you for your help.

The problem is your binding inside a DataTemplate: WPF tries to find the property path ShowRightGridCommand on your MediaDetail class, because the ItemsControl sets the data context for each item container it generates to the corresponding item.
What you actually want to do is binding to the view model. You can do this like so:
{Binding ElementName=LeftGrid, Path=DataContext.ShowRightGridCommand}
LeftGrid is an element outside of the ItemsControl. Its DataContext is your MoviePanelViewModel instance, and there is your ShowRightGridCommand property defined.
A little cleaner would be to put the name root on your view's root control (usually a UserControl or Window), and then use ElementName=root,Path=DataContext.... as your binding - at least that's what I usually do.
An alternative would be to use RelativeSource={RelativeSource UserControl}, but I find ElementName=root to be simpler.

wpf check list box

I m new to wpf.In order to get check list box functionality ,I have added below xaml to my code,but there is no output in my screen.only blank,what it could be?
<TabItem Header="Samples" >
<ListBox Margin="10" Width="373" Height="236">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="MyText"/>
<CheckBox IsChecked="False"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</TabItem>

just have a look at this basic sample
http://merill.net/2009/10/wpf-checked-listbox/

List box is a bit wired for such task..Have a look at ItemsControl.
Here is the code i use:
<ItemsControl
ItemsSource="{Binding ***}" IsTabStop="False">
<ItemsControl.ItemTemplate>
<DataTemplate>
<CheckBox
Content="{Binding Name}"
IsChecked="{Binding IsSelected}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>

Replace your code with this
<TabItem Header="Roles" >
<ListBox Margin="10" Width="373" Height="236">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="MyText"/>
<CheckBox IsChecked="False"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
<ListBoxItem>Hi</ListBoxItem>
</ListBox>
</TabItem>
and tell us if it still shows blank

Better still, just use the new CheckListBox control in the Extended WPF Toolkit
http://wpftoolkit.codeplex.com/wikipage?title=CheckListBox&referringTitle=Home

This might help
1.Inorder to work datatemplate you must specify itemsource, here i have bounded a Stateslist a collection of items into it.
2.Also set the Datacontext to ViewModel or the CodeBehind as datacontext.
3.Datacontext will distribute the StateList properties collection to the listbox itemsource
using codebehind -
public Window1()
{
InitializeComponent();
this.DataContext = this;
LoadData();
}
using viewmodel
public Window1()
{
InitializeComponent();
DataContext = new Window1ViewModel();
LoadData();
}
//MyItemsource Property for listbox
private ObservableCollection<States> _stateslist;
public ObservableCollection<States> StatesList
{
get { return _stateslist; }
set
{
_stateslist = value;
RaisePropertyChanged(() => StatesList);
}
}
// Sample Data Loading
public void LoadData()
{
StatesList = new ObservableCollection<States>();
StatesList.Add(new States
{
StateName = "Kerala"
});
StatesList.Add(new States
{
StateName = "Karnataka"
});
StatesList.Add(new States
{
StateName = "Goa"
});
}
Window1.Xaml
<ListBox ItemsSource="{Binding StatesList}" >
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel>
<CheckBox IsChecked="{Binding IsSelected"} Content="{Binding StateName}" />
<TextBox Text="{Binding TextBoxValue}" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>

Check this out it isworking..you are using TabItem but you didnt define it in TabControl
<TabControl>
<TabItem Header="Tab1">
<ListBox Margin="10" Width="373" Height="236">
<ListBox.Items>
<StackPanel Orientation="Horizontal">
<TextBlock Text="MyText"/>
<CheckBox IsChecked="False"/>
</StackPanel>
</ListBox.Items>
</ListBox>
</TabItem>
</TabControl>
If you are new in WPF use XamlPadX it will give you great help to practice out on it..

How to access base datacontext in Collection in xaml

I have a wpf app with the datacontext set to an instance of a viewmodel class. It all works fine except where I need to access a property of the viewmodel in a listbox with the datacontext set to a collection that is contained in the ViewModel class. On msdn it says you can escape using the \ character but that has not worked for me
My code
public class StatusBoardViewModel : INotifyPropertyChanged
{
OIConsoleDataContext db = new OIConsoleDataContext();
// the collection
private IQueryable<Issue> issues;
public IQueryable<Issue> Issues
{
get
{
// Lazy load issues if they have not been instantiated yet
if (issues == null)
QueryIssues(); // This just runs a linq query to set the property
return issues;
}
set
{
if (issues != value)
{
issues = value;
OnPropertyChanged("Issues");
}
}
}
// The property I need to access
private bool showDetailListItems = true;
public bool ShowDetailListItems
{
get
{
return showDetailListItems;
}
set
{
if (showDetailListItems != value)
{
showDetailListItems = value;
OnPropertyChanged("ShowDetailListItems");
}
}
}
}
in the window1.xaml.cs
//instantiate the view model
StatusBoardViewModel statusBoardViewModel = new StatusBoardViewModel();
public Window1()
{
InitializeComponent();
// setting the datacontext
this.DataContext = statusBoardViewModel;
}
And the Xaml
// This is in the Window1.xaml file
<ListBox x:Name="IssueListBox"
ItemsSource="{Binding Issues}" // Binds the listbox to the collection in the ViewModel
ItemTemplate="{StaticResource ShowIssueDetail}"
IsSynchronizedWithCurrentItem="True"
HorizontalContentAlignment="Stretch" BorderThickness="3"
DockPanel.Dock="Top" VerticalContentAlignment="Stretch"
Margin="2" MinHeight="50" />
// The datatemplate from the app.xaml file
<DataTemplate x:Key="ShowIssueDetail">
<Border CornerRadius="3" Margin="2" MinWidth="400" BorderThickness="2"
BorderBrush="{Binding Path=IssUrgency, Converter={StaticResource IntToRYGBBoarderBrushConverter}}">
<StackPanel Orientation="Vertical">
<TextBlock Text="{Binding Path=IssSubject}" Margin="3" FontWeight="Bold" FontSize="14"/>
<!--DataTrigger will collapse following panel for simple view-->
<StackPanel Name="IssueDetailPanel" Visibility="Visible" Margin="3">
<StackPanel Width="Auto" Orientation="Horizontal">
<TextBlock Text="Due: " FontWeight="Bold"/>
<TextBlock Text="{Binding Path=IssDueDate}" FontStyle="Italic" HorizontalAlignment="Left"/>
</StackPanel>
<StackPanel Width="Auto" Orientation="Horizontal">
<TextBlock Text="Category: " FontWeight="Bold"/>
<TextBlock Text="{Binding Path=IssCategory}"/>
</StackPanel>
</StackPanel>
</StackPanel>
</Border>
// This is where I have the issue, ShowDetailListItems is in the base class, not the collection
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding Path=ShowDetailListItems, Mode=TwoWay}" Value="False">
<Setter TargetName="IssueDetailPanel" Property="Visibility" Value="Collapsed"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
I have learned a TON doing this but this current issue is driving me batty, no luck with google, MSDN, SO or a couple books
I thought I would add this note: I am learning this in order to build some apps for my business, I am a rank beginner in wpf and xaml so I relize this is probably somthing silly. I would really like to find a good tutorial on datacontexts as what I do find is a dozen different "How To's" that are all totally different. I know I have some big holes in my knowledge because I keep ending up with multiple instantiations of my viewmodel class when I try to create references to my datacontext in the codebehind, Window1.xaml and app.xaml files.

Have you tried one of these?
{Binding Path=ShowDetailListItems, ElementName=YourWindowName}
or
{Binding ShowDetailListItems, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}}