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How can I use 2 data bindings for an ItemSource Data Template in WPF App

I have a counter which increments depending on a foreach Loop from:
public partial class UserControlCounter : UserControl, INotifyPropertyChanged
{
private int _scanStatusCounter;
public int ScanStatusCounter
{
get { return _scanStatusCounter; }
set { _scanStatusCounter = value; NotifyPropertyChanged(); }
}
public UserControlCounter()
{
InitializeComponent();
DataContext = this;
}
private async void Button_Click(object sender, RoutedEventArgs e)
{
await Task.Run(getAll);
scanStatus.Text = "Persons " + ScanStatusCounter.ToString();
}
private async void getAll()
{
//grab data and iterate it
string[] string_array = new string[] { "a", "b", "c", "d", "e" }; // type = System.String[]
foreach (var i in string_array)
{
ScanStatusCounter++;
await Task.Delay(100);
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
and the Xaml:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="150"/>
<ColumnDefinition Width="auto"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="60"/>
</Grid.RowDefinitions>
<ListBox Grid.Row="0" Grid.Column="0" Name="myListBox" Height="40" ></ListBox>
<TextBlock Grid.Row="0" Grid.Column="1" Name="scanStatus" Height="40" Text="{Binding Path=ScanStatusCounter, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"></TextBlock>
<Button Grid.Row="0" Grid.Column="2" Click="Button_Click" Height="40">Click Me</Button>
</Grid>
That works fine and increments "live", but my problem is that I need to get that now running inside a more complex Data Template.
I've tried to inject the Counter onClick with:
private async void Button_Click(object sender, RoutedEventArgs e)
{
var btn = sender as Button;
var contentPresenter = (btn.TemplatedParent as ContentPresenter);
var ppStatusCounter = contentPresenter.ContentTemplate.FindName("scanStatus", contentPresenter) as TextBlock;
ppStatusCounter.Text = "Entrys found: " + ScanStatusCounter.ToString();
}
But then I get the Value only onClick not like a live incrementing Counter, that's my Data Template:
<UserControl.Resources>
<c1:NameList x:Key="NameListData"/>
<DataTemplate x:Key="NameItemTemplate">
<Grid Margin="2">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="auto"/>
<ColumnDefinition Width="100" />
<ColumnDefinition Width="100" />
<ColumnDefinition Width="100" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="40"></RowDefinition>
<RowDefinition Height="40"></RowDefinition>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Grid.Column="0" Text="Domaine"/>
<TextBox Grid.Row="1" Grid.Column="0" x:Name="txtDomainName" Text="{Binding Path=DomaineName}" Margin="0,0,5,0"></TextBox>
<Button Grid.Row="1" Grid.Column="1" Width="100" Height="30" Margin="5,5,5,5" x:Name="btnNames" Click="Button_Click" Content="Start Scan" />
<Grid Grid.Column="2" Grid.Row="1" Height="20">
<ProgressBar x:Name="pbStatus" Height="20" Width="100" Minimum="0" Maximum="100" Visibility="Hidden"/>
<TextBlock x:Name="pbStatusText" HorizontalAlignment="Center" VerticalAlignment="Center" Text="Scanning" Visibility="Hidden"/>
</Grid>
<TextBlock Grid.Column="3" Grid.Row="1" Name="scanStatus" Text="{Binding Path=ScanStatusCounter, UpdateSourceTrigger=PropertyChanged}"/>
</Grid>
</DataTemplate>
</UserControl.Resources>
<Grid>
<StackPanel Orientation="Horizontal" VerticalAlignment="top">
<StackPanel Orientation="Horizontal" Margin="0,20,0,0">
<ListBox x:Name="lstDomainNames"
Margin="5,5,5,5"
ItemsSource="{Binding Source={StaticResource NameListData}}"
ItemTemplate="{StaticResource NameItemTemplate}"
IsSynchronizedWithCurrentItem="True"/>
</StackPanel>
</StackPanel>
</Grid>
that's my Data Source Class, not much there:
public partial class NameList : ObservableCollection<SetCredentials>
{
private static Logger logger = LogManager.GetCurrentClassLogger();
public NameList() : base()
{
using var forest = Forest.GetCurrentForest();
Forest currentForest = Forest.GetCurrentForest();
DomainCollection domains = currentForest.Domains;
foreach (Domain objDomain in domains)
{
Add(new SetCredentials(objDomain.ToString()));
}
}
}
public class SetCredentials
{
private string domainName;
public SetCredentials(string domain)
{
this.domainName = domain;
}
public string DomaineName
{
get { return domainName; }
set { domainName = value; }
}
}
Do I have to add a second Data Binding source to my ItemSource or do I need another approach for this, for example in my TextBox Binding?

Get index of data binding from ItemsControl

Is there any way to get the index of the data which is binded to the ItemsControl, when a button is clicked?
<ItemsControl x:Name="ic_schranke" DataContext="{Binding Schranke}" >
<ItemsControl.ItemTemplate>
<DataTemplate >
<Button Height="80" x:Name="btn_open" Click="btn_open_Click" HorizontalAlignment="Stretch" Style="{StaticResource TransparentStyle}">
<Grid HorizontalAlignment="Stretch">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*"/>
<ColumnDefinition Width="2*"/>
<ColumnDefinition Width="1*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="1*"/>
<RowDefinition Height="30*"/>
<RowDefinition Height="1*"/>
</Grid.RowDefinitions>
<Rectangle x:Name="rect" Grid.ColumnSpan="3" Grid.Row="1" Opacity="0.65" Grid.Column="0" Fill="#FFCEEAFF"/>
<Border CornerRadius="25" Height="50" Width="50" HorizontalAlignment="Center" Grid.Column="0" Grid.Row="1">
<Border.Background>
<ImageBrush ImageSource="/Assets/schranken.jpg" />
</Border.Background>
</Border>
<TextBlock Name="schranken_name" Grid.Column="1" Grid.Row="1" Text="{Binding name}" VerticalAlignment="Center" HorizontalAlignment="Center" FontWeight="ExtraLight" Foreground="Black" />
</Grid>
</Button>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
Here is the sample data which is binded to the IC:
List<Schranke> elements;
public UserPage()
{
this.InitializeComponent();
elements = new List<Schranke>();
for (var i = 1; i < 15; i++)
elements.Add(new Schranke() { name = $"Schranke NR:{i}" });
this.ic_schranke.ItemsSource = elements;
}
And here is the code in the button click event:
private async void btn_open_Click(object sender, RoutedEventArgs e)
{
Grid grid = (sender as Button).Content as Grid;
//Debug.WriteLine($"content {tb.Text} clicked");
var tmp_background = grid.Background;
grid.Background = new SolidColorBrush(new Windows.UI.Color() { A = 255, R = 78, G = 170, B = 44 });
VibrationDevice testVibrationDevice = VibrationDevice.GetDefault();
testVibrationDevice.Vibrate(System.TimeSpan.FromMilliseconds(150));
await Task.Delay(3000);
grid.Background = tmp_background;
}

Maybe something along the lines of this:
the presenter - put this in the data context
public class SchrankePresenter : INotifyPropertyChanged
{
private List<Schranke> _elements;
public List<Schranke> Elements
{
get { return _elements; }
set
{
_elements = value;
OnPropertyChanged("Elements");
}
}
public ICommand ClickCommand { get; set; }
private void OnPropertyChanged(string propName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));
}
public event PropertyChangedEventHandler PropertyChanged;
public SchrankePresenter()
{
var elements = new List<Schranke>();
for (var i = 1; i < 15; i++)
elements.Add(new Schranke() { Name = $"Schranke NR:{i}" });
Elements = elements;
ClickCommand = new DelegateCommand(ClickAction);
}
public void ClickAction(Schranke item)
{
VibrationDevice.GetDefault().Vibrate(TimeSpan.FromMilliseconds(150));
}
}
public class Schranke
{
public string Name { get; set; }
}
the template:
<ListView ItemsSource="{Binding Elements}">
<ListView.ItemTemplate>
<DataTemplate>
<Button Height="80"
HorizontalAlignment="Stretch"
Command="{Binding ClickCommand}"
Style="{StaticResource TransparentStyle}">
<Grid HorizontalAlignment="Stretch">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1*" />
<ColumnDefinition Width="2*" />
<ColumnDefinition Width="1*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="1*" />
<RowDefinition Height="30*" />
<RowDefinition Height="1*" />
</Grid.RowDefinitions>
<Rectangle x:Name="rect"
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="3"
Fill="#FFCEEAFF"
Opacity="0.65" />
<Border Grid.Row="1"
Grid.Column="0"
Width="50"
Height="50"
HorizontalAlignment="Center"
CornerRadius="25">
<Border.Background>
<ImageBrush ImageSource="/Assets/schranken.jpg" />
</Border.Background>
</Border>
<TextBlock Name="schranken_name"
Grid.Row="1"
Grid.Column="1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
FontWeight="ExtraLight"
Foreground="Black"
Text="{Binding Name}" />
</Grid>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
you can do the background animation using a storyboard/visualstate
EDIT : regarding the DelegateCommand, it's a simple implementation I use for my WPF apps -
internal class DelegateCommand<T> : ICommand
{
private Action<T> _clickAction;
public DelegateCommand(Action<T> clickAction)
{
_clickAction = clickAction;
}
public event EventHandler CanExecuteChanged;
public bool CanExecute(object parameter)
{
return true;
}
public void Execute(object parameter)
{
_clickAction((T)parameter);
}
}

Windows Phone 8.1 Hub Section Update Items (INotifyPropertyChanged)

I am trying to build a diary app that uses hub as user interface and update the UI after saving the diary. I already implemented the INotifyPropertyChanged but it didn't work. I want the item that is added after saving to appear on the hub immediately.
public class SampleDataGroup : INotifyPropertyChanged
{
public SampleDataGroup()
{
UniqueId = string.Empty;
Title = string.Empty;
Subtitle = string.Empty;
Description = string.Empty;
ImagePath = string.Empty;
Items = new ObservableCollection<DiaryData>();
}
public string UniqueId { get; private set; }
public string Title { get; private set; }
public string Subtitle { get; private set; }
public string Description { get; private set; }
public string ImagePath { get; private set; }
private ObservableCollection<DiaryData> _items;
public ObservableCollection<DiaryData> Items { get{return _items;} private set
{
OnPropertyChanged("Items");
_items = value;
} }
public override string ToString()
{
if (this.Title != null)
{
return this.Title;
}
else
{
System.Diagnostics.Debug.WriteLine("this is null at tostring");
return null;
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void OnPropertyChanged(string name)
{
PropertyChangedEventHandler handler = PropertyChanged;
if (handler != null)
{
handler(this, new PropertyChangedEventArgs(name));
}
}
}
public sealed class SampleDataSource : INotifyPropertyChanged
{
private static SampleDataSource _sampleDataSource = new SampleDataSource();
private ObservableCollection<SampleDataGroup> _groups = new ObservableCollection<SampleDataGroup>();
public ObservableCollection<SampleDataGroup> Groups
{
get { return this._groups; }
set { }
}
public static async Task<IEnumerable<SampleDataGroup>> GetGroupsAsync()
{
await _sampleDataSource.GetSampleDataAsync();
return _sampleDataSource.Groups;
}
public static async Task<SampleDataGroup> GetGroupAsync(string uniqueId)
{
System.Diagnostics.Debug.WriteLine("GetGroupAsync is entered phase 1");
await _sampleDataSource.GetSampleDataAsync();
// Simple linear search is acceptable for small data sets
System.Diagnostics.Debug.WriteLine("GetGroupAsync is entered phase 2");
var matches = _sampleDataSource.Groups.Where((group) => group.UniqueId.Equals(uniqueId));
if (matches.Count() == 1) return matches.First();
return null;
}
public static async Task<DiaryData> GetItemAsync(string uniqueId)
{
await _sampleDataSource.GetSampleDataAsync();
System.Diagnostics.Debug.WriteLine("GetItemAsync is entered");
// Simple linear search is acceptable for small data sets
var matches = _sampleDataSource.Groups.SelectMany(group => group.Items).Where((item) => item.UniqueId.Equals(uniqueId));
if (matches.Count() == 1) return matches.First();
else return null;
}
private async Task GetSampleDataAsync()
{
System.Diagnostics.Debug.WriteLine("GetSampleDataAsync is entered");
//if (this._groups.Count != 0)return;
Uri dataUri = new Uri("ms-appdata:///local/data.json");
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(dataUri);
string jsonText = await FileIO.ReadTextAsync(file);
JsonArray jsonArray = JsonArray.Parse(jsonText);
SampleDataGroup group = new SampleDataGroup();
foreach (JsonValue itemValue in jsonArray)
{
JsonObject itemObject = itemValue.GetObject();
group.Items.Add(new DiaryData(itemObject["Title"].GetString(),
itemObject["Content"].GetString(),
itemObject["Coordinate"].GetString(),
itemObject["UniqueId"].GetString(),
itemObject["ImagePath"].GetString(),
itemObject["VideoPath"].GetString()));
System.Diagnostics.Debug.WriteLine(itemObject["Title"].GetString());
}
this.Groups.Add(group);
System.Diagnostics.Debug.WriteLine("GetSampleDataAsync is finished");
}
//}
public event PropertyChangedEventHandler PropertyChanged;
}
here's my XAML File
<Page
x:Class="DiaryAppHub.HubPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:DiaryAppHub"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:data="using:DiaryAppHub.Data"
DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
d:DataContext="{Binding Source={d:DesignData Source=/DataModel/SampleData.json, Type=data:data.json}}"
mc:Ignorable="d">
<Page.Resources>
<DataTemplate x:Key="HubSectionHeaderTemplate">
<TextBlock Margin="0,0,0,-9.5" Text="{Binding}"/>
</DataTemplate>
<!-- Grid-appropriate item template as seen in section 2 -->
<DataTemplate x:Key="Standard200x180TileItemTemplate">
<Grid Margin="0,0,9.5,9.5" Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="138.5" Width="138.5"/>
<TextBlock Text="{Binding Title}" VerticalAlignment="Bottom" Margin="9.5,0,0,6.5" Style="{ThemeResource BaseTextBlockStyle}"/>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardTripleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}"/>
<TextBlock Text="{Binding Description}" Style="{ThemeResource ListViewItemContentTextBlockStyle}" Foreground="{ThemeResource PhoneMidBrush}" />
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" />
</StackPanel>
</Grid>
</DataTemplate>
<DataTemplate x:Key="StandardDoubleLineItemTemplate">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border Background="{ThemeResource ListViewItemPlaceholderBackgroundThemeBrush}" Margin="0,9.5,0,0" Grid.Column="0" HorizontalAlignment="Left">
<Image Source="{Binding ImagePath}" Stretch="UniformToFill" AutomationProperties.Name="{Binding Title}" Height="79" Width="79"/>
</Border>
<StackPanel Grid.Column="1" Margin="14.5,0,0,0">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}" Foreground="Black"/>
<TextBlock Text="{Binding Subtitle}" Style="{ThemeResource ListViewItemSubheaderTextBlockStyle}" Foreground="DimGray"/>
</StackPanel>
</Grid>
</DataTemplate>
</Page.Resources>
<Page.BottomAppBar>
<CommandBar Background="Transparent">
<AppBarButton Icon="Add" Label="Add" Click="add_onclick"/>
<AppBarButton Icon="Add" Label="Shake it!" />
</CommandBar>
</Page.BottomAppBar>
<Grid x:Name="LayoutRoot">
<Hub x:Name="Hub" x:Uid="Hub" Header="diary app hub" Margin="0,0,0,-59" Foreground="DimGray">
<Hub.Background>
<ImageBrush ImageSource="ms-appx:/Assets/desk_paper.png" Stretch="None"/>
</Hub.Background>
<!--<HubSection x:Uid="HubSection1" Header="SECTION 1" DataContext="{Binding Groups}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}">
<DataTemplate>
<ListView
ItemsSource="{Binding}"
IsItemClickEnabled="True"
ItemClick="GroupSection_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0,0,0,27.5">
<TextBlock Text="{Binding Title}" Style="{ThemeResource ListViewItemTextBlockStyle}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</DataTemplate>
</HubSection>-->
<HubSection x:Uid="HubSection5" Header="Recent"
DataContext="{Binding Groups[0]}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}">
<DataTemplate>
<ListView
AutomationProperties.AutomationId="ItemListViewSection5"
AutomationProperties.Name="Items In Group"
SelectionMode="None"
IsItemClickEnabled="True"
ItemsSource="{Binding Items}"
ItemTemplate="{StaticResource StandardDoubleLineItemTemplate}"
ItemClick="ItemView_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
</ListView>
</DataTemplate>
</HubSection>
<HubSection x:Uid="HubSection2" Header="All notes" Width ="Auto"
DataContext="{Binding Groups[0]}" HeaderTemplate="{ThemeResource HubSectionHeaderTemplate}" Height="659" >
<DataTemplate>
<GridView
Margin="0,9.5,0,0"
ItemsSource="{Binding Items}"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Items In Group"
ItemTemplate="{StaticResource Standard200x180TileItemTemplate}"
SelectionMode="None"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick"
ContinuumNavigationTransitionInfo.ExitElementContainer="True">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<ItemsWrapGrid />
</ItemsPanelTemplate>
</GridView.ItemsPanel>
</GridView>
</DataTemplate>
</HubSection>
</Hub>
</Grid>

You need to raise the PropertyChanged event for the model's properties. The UI doesn't get notified as properties like Title,Subtitle don't raise the PropertyChanged event when they are modified. It should be like this:
private string _title;
public string Title
{
get
{
return _title;
}
set
{
if(_title!=value)
{
_title=value;
OnPropertyChanged("Title");
}
}
}
Do this similarly for other properties. Also, you don't need to raise the PropertyChanged event for an ObservableCollection as an ObservableCollection implements INotifyPropertyChanged by default.

ListBox Data Control Isn't Showing Information

First time using a ListBox and after following this , I'm having issues having data actually display. The ListBox is just empty and white with no text in it.
I made a separate textbox to test an individual "Tweet" object out and it is indeed outputting what I want it to. I think my issue either lies in XAML or Tweets. But nothing looks out of place.
Tracing reveals that Tweets successfully adds a proper Tweet object with what I need. But my ListBox Count is always 0.
<Grid Opacity="0.8">
<Grid.Resources>
<local:Tweets x:Key="tweets"/>
</Grid.Resources>
<Rectangle Fill="Gray" Margin="1523,0,0,729" Height="321" Width="389">
<Rectangle.Effect>
<DropShadowEffect/>
</Rectangle.Effect></Rectangle>
<ListBox ItemsSource="{StaticResource tweets}" Height="321" Margin="340,40,1096,0" x:Name="twitterBox" VerticalAlignment="Top" Width="476">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="132">
<!--<Image Source="{Binding imgSrc}" Height="73" Width="73" VerticalAlignment="Top" Margin="0,10,8,0"/>-->
<StackPanel Width="370">
<TextBlock Text="{Binding user}" FontSize="28" />
<TextBlock Text="{Binding tweet}" TextWrapping="Wrap" FontSize="24" />
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
In my cs:
public class Tweet
{
public String imgSrc { get; set; }
public String user { get; set; }
public String tweet { get; set; }
public Tweet(String user, String tweet, String img)
{
this.imgSrc = img;
this.user = user;
this.tweet = tweet;
}
}
public class Tweets : ObservableCollection<Tweet>
{
public Tweets()
{
}
public void addTweet(Tweet tweet)
{
Add(tweet);
}
}
public void SomeFunction()
{
Tweets myTwitter = new Tweets();
myTwitter.addTweet(new Tweet(tweet.User.ScreenName, tweet.Text, tweet.User.ProfileImageUrl));
}

ItemTemplate code is ok but you should remove this Margin="1523,0,0,729".
ListBox is empty because items source is empty. You should add some items.
To add items in XAML you should add default constructor to Tweet class.
public class Tweet
{
public String imgSrc { get; set; }
public String user { get; set; }
public String tweet { get; set; }
public Tweet(){}
public Tweet(String user, String tweet, String img)
{
this.imgSrc = img;
this.user = user;
this.tweet = tweet;
}
}
And now you can write something like this:
...
<Grid.Resources>
<local:Tweets x:Key="tweets">
<local:Tweet imgSrc="imgSrc1" user="user1" tweet="tweet1" />
<local:Tweet imgSrc="imgSrc2" user="user2" tweet="tweet2" />
</local:Tweets>
</Grid.Resources>
...
Result:
Add items in code-behind.
To do that you should use function: FindResource (msdn).
XAML:
<Grid Name="mainGrid" Opacity="0.8">
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.Resources>
<local:Tweets x:Key="tweets">
<local:Tweet imgSrc="imgSrc1" user="user1" tweet="tweet1" />
<local:Tweet imgSrc="imgSrc2" user="user2" tweet="tweet2" />
</local:Tweets>
</Grid.Resources>
<Button Content="Add new item" Click="Button_Click" />
<ListBox x:Name="twitterBox" ItemsSource="{StaticResource tweets}"
VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
Grid.Row="1">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="132">
<!--<Image Source="{Binding imgSrc}" Height="73" Width="73" VerticalAlignment="Top" Margin="0,10,8,0"/>-->
<StackPanel Width="370">
<TextBlock Text="{Binding user}" FontSize="28" />
<TextBlock Text="{Binding tweet}" TextWrapping="Wrap" FontSize="24" />
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
Code-behind:
private void Button_Click(object sender, RoutedEventArgs e)
{
var coll = mainGrid.FindResource("tweets") as Tweets;
if (coll != null)
{
coll.Add(new Tweet("user", "name", "url"));
}
}
Second solution:
The better solution will be if you will create an instance of class Tweets in code behind.
XAML:
<Grid Name="mainGrid" Opacity="0.8">
<Grid.RowDefinitions>
<RowDefinition Height="30" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Button Content="Add new item" Click="Button_Click" />
<ListBox x:Name="twitterBox" ItemsSource="{Binding tweets}"
VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
Grid.Row="1">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="132">
<!--<Image Source="{Binding imgSrc}" Height="73" Width="73" VerticalAlignment="Top" Margin="0,10,8,0"/>-->
<StackPanel Width="370">
<TextBlock Text="{Binding user}" FontSize="28" />
<TextBlock Text="{Binding tweet}" TextWrapping="Wrap" FontSize="24" />
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
Code-behind:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
tweets = new Tweets();
tweets.Add(new Tweet("user1", "name1", "url1"));
tweets.Add(new Tweet("user2", "name2", "url2"));
tweets.Add(new Tweet("user3", "name3", "url3"));
this.DataContext = this;
}
public Tweets tweets { get; set; }
private void Button_Click(object sender, RoutedEventArgs e)
{
tweets.Add(new Tweet("user4", "name4", "url4"));
}
}

You add tweets to a different collection than the one displayed by the listbox.

WPF Data Binding not showing

So I'm having what should be a simple XAML Data Binding error. I've got the below XAML with two classes (so far) that they used for DataBinding, a Row, which contains an ObservableCollection rows. The nodes have a bunch of extra associated information and I'm trying to show these nodes in a grid-like fashion (it's going to be used for a path-finding algorithm.)
The problem is that the "Here" TextBlock doesn't show up. But I know that the Nodes are getting bound properly because their values show up in the Debugging StackPanel.
<Window.Resources>
<local:Row x:Key="TestRow">
<local:Node x="0" y="0" Cost="20" />
<local:Node x="0" y="1" Cost="20" />
<local:Node x="0" y="2" Cost="20" />
</local:Row>
</Window.Resources>
<Grid Name="MainGrid" Margin="10,10,10,10" >
<Grid.RowDefinitions>
<RowDefinition Height="150" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100" />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<StackPanel Margin="0,25,0,0"
DataContext="{Binding ElementName=AStarListView,
Path=SelectedItem}"
x:Name="Debugging" Orientation="Vertical" >
<TextBlock Text="{Binding x}" />
<TextBlock Text="{Binding y}" />
<TextBlock Text="{Binding Cost}" />
</StackPanel>
<ListView Grid.RowSpan="2" Margin="2,2,2,2" Grid.Column="1"
x:Name="AStarListView"
ItemsSource="{StaticResource TestRow}" >
<ListView.ItemTemplate>
<DataTemplate DataType="local:Row">
<ListView ItemsSource="{Binding nodes}" Width="48" Height="48" >
<ListView.ItemTemplate>
<DataTemplate DataType="local:Node">
<TextBlock Text="Here" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Here's the (stripped) Node class.
public class Node : INotifyPropertyChanged
{
public Tuple<int, int> coordinates { get; set; }
public int x
{
get
{
if (this.coordinates == null)
return -1;
return this.coordinates.Item1;
}
set
{
if (this.coordinates != null)
this.coordinates = new Tuple<int, int>(value, y);
else
this.coordinates = new Tuple<int, int>(value, -1);
OnPropertyChanged("x");
}
}
public int y
{
get
{
if (this.coordinates == null)
return -1;
return this.coordinates.Item2;
}
set
{
if (this.coordinates != null)
this.coordinates = new Tuple<int, int>(x, value);
else
this.coordinates = new Tuple<int, int>(-1, value);
OnPropertyChanged("y");
}
}
private Node _parent;
private int _Cost;
public int Cost
{
get
{
return _Cost;
}
set
{
_Cost = value;
OnPropertyChanged("Cost");
}
}
protected void OnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChangedEventArgs args =
new PropertyChangedEventArgs(propertyName);
this.PropertyChanged(this, args);
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
Here's the Row class:
public class Row : ObservableCollection<Node>
{
public ObservableCollection<Node> nodes { get; set; }
public Row()
{
this.nodes = new ObservableCollection<Node>();
}
}

Here's the corrected XAML, the class definitions are correct in the question, need to replace "AStarListView" with this XAML.
<ListView Grid.RowSpan="2" Margin="2,2,2,2" Grid.Column="1" x:Name="AStarListView"
ItemsSource="{StaticResource TestRow}" >
<ListView.ItemTemplate>
<DataTemplate DataType="local:Node">
<Grid Background="#dddddd" >
<TextBlock Grid.Row="0" Grid.Column="0" Text="{Binding x}"/>
<TextBlock Grid.Row="0" Grid.Column="1" Text="{Binding y}"/>
<TextBlock Grid.Row="1" Grid.Column="0" Text="{Binding Cost}"/>
<Grid.RowDefinitions>
<RowDefinition Height="24"/>
<RowDefinition Height="24"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="24"/>
<ColumnDefinition Width="24"/>
</Grid.ColumnDefinitions>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
My problem was that I had the ListViews too deeply nested. The inner ListView was binding to the "nodes" property of a Node, which didn't exist.