Develop Reference

Draw variable number of rectangles within WPF Grid cells?

I have a WPF Grid which is 3 columns wide and 8 rows:
<Window x:Class="Container.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="700" Width="1000">
<Grid ShowGridLines="True">
<Grid.RowDefinitions>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
<RowDefinition Height="20"></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="10*" />
<ColumnDefinition Width="1*" />
<ColumnDefinition Width="10*" />
</Grid.ColumnDefinitions>
</Grid>
</Window>
I am using this to draw something like this:
Every cell in the first and third columns may have a different number of rectangles. Also, the width of each rectangle may be different and change at run-time. The width will be proportionate to a number (known at run-time and continually-changing).
What is the best way to draw these rectangles?

Here is what I've come up with after about an hour of fiddling (GitHub Repo):
I'm using the MVVM pattern to make the UI as easy as possible. Right now, it just populates with some random data.
The XAML:
<Window
x:Class="BuySellOrders.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:BuySellOrders"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Title="MainWindow"
Width="800"
Height="450"
mc:Ignorable="d">
<Window.DataContext>
<local:MainWindowVm />
</Window.DataContext>
<Grid Margin="15">
<ItemsControl ItemsSource="{Binding Path=Prices}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="1" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate DataType="{x:Type local:PriceEntryVm}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Border
Grid.Column="0"
Padding="5"
HorizontalAlignment="Stretch"
BorderBrush="Black"
BorderThickness="1">
<ItemsControl HorizontalAlignment="Right" ItemsSource="{Binding Path=BuyOrders}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate DataType="{x:Type local:OrderVm}">
<Border
Width="{Binding Path=Qty}"
Margin="5"
Background="red"
BorderBrush="Black"
BorderThickness="1" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Border>
<Border
Grid.Column="1"
BorderBrush="Black"
BorderThickness="1">
<TextBlock
Margin="8"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{Binding Path=Price}" />
</Border>
<Border
Grid.Column="2"
Padding="5"
BorderBrush="Black"
BorderThickness="1">
<ItemsControl ItemsSource="{Binding Path=SellOrders}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate DataType="{x:Type local:OrderVm}">
<Border
Width="{Binding Path=Qty}"
Margin="5"
Background="red"
BorderBrush="Black"
BorderThickness="1" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Border>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</Window>
The view models:
class MainWindowVm : ViewModel
{
public MainWindowVm()
{
var rnd = new Random();
Prices = new ObservableCollection<PriceEntryVm>();
for (int i = 0; i < 8; i++)
{
var entry = new PriceEntryVm();
Prices.Add(entry);
entry.BuyOrders.CollectionChanged += OnOrderChanged;
entry.SellOrders.CollectionChanged += OnOrderChanged;
entry.Price = (decimal)110.91 + (decimal)i / 100;
var numBuy = rnd.Next(5);
for (int orderIndex = 0; orderIndex < numBuy; orderIndex++)
{
var order = new OrderVm();
order.Qty = rnd.Next(70) + 5;
entry.BuyOrders.Add(order);
}
var numSell = rnd.Next(5);
for (int orderIOndex = 0; orderIOndex < numSell; orderIOndex++)
{
var order = new OrderVm();
order.Qty = rnd.Next(70) + 5;
entry.SellOrders.Add(order);
}
}
}
private void OnOrderChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.Action == NotifyCollectionChangedAction.Add)
{
foreach (var item in e.NewItems)
{
var order = item as OrderVm;
if (order.Qty > LargestOrder)
{
LargestOrder = order.Qty;
}
}
}
}
private int _largestOrder;
public int LargestOrder
{
get { return _largestOrder; }
private set { SetValue(ref _largestOrder, value); }
}
public ObservableCollection<PriceEntryVm> Prices { get; }
}
public class PriceEntryVm: ViewModel
{
public PriceEntryVm()
{
BuyOrders = new OrderList(this);
SellOrders = new OrderList(this);
}
private Decimal _price;
public Decimal Price
{
get {return _price;}
set {SetValue(ref _price, value);}
}
public OrderList BuyOrders { get; }
public OrderList SellOrders { get; }
}
public class OrderList : ObservableCollection<OrderVm>
{
public OrderList(PriceEntryVm priceEntry)
{
PriceEntry = priceEntry;
}
public PriceEntryVm PriceEntry { get; }
}
public class OrderVm : ViewModel
{
private int _qty;
public int Qty
{
get { return _qty; }
set { SetValue(ref _qty, value); }
}
}
I had to make some assumptions about the naming of things, but hopefully you should get the basic idea of what's going on.
It's structured as a list of PriceEntry, each of which contains a Price, and a BuyOrders and SellOrders properties.
BuyOrders and SellOrders are just lists of orders that have a Quantity property.
The XAML binds the list of price entries to a template that contains a 3 column grid. The first and 3rd columns of that grid bound to another set of item controls for each list of orders. The template for each order is just a border with a Width bound to the Quantity of the order.
All the binds means that just updating a property, or adding an order to either the buy or sell list of a price entry will automatically propagate to the UI. Adding or removing a PriceEntry will also automatically adjust the UI.
I haven't implemented your automatic scaling yet, but the basic idea would be to use a ValueConverter on the Quantity binding, to make it automatically adjust to the largest order.
As an extra note, it uses this nuget package to provide some of the MVVM boiler-plate code, but you should be able to use anything you want, as long as it gives you INotifyPropertyChanged support.
Here is a bonus screen capture showing the dynamic nature of MVVM updating the UI based on a timer.
This only needed a few lines of code to randomly pick a row, then randomly pick an order on the row, then add or subtract a small random amount from the quantity.
_updateTimer = new DispatcherTimer();
_updateTimer.Tick += OnUpdate;
_updateTimer.Interval = TimeSpan.FromSeconds(0.01);
_updateTimer.Start();
private void OnUpdate(object sender, EventArgs e)
{
var entryIndex = _rnd.Next(Prices.Count);
var entry = Prices[entryIndex];
OrderList list;
list = _rnd.Next(2) == 1 ?
entry.BuyOrders :
entry.SellOrders;
if (list.Any())
{
var order = list[_rnd.Next(list.Count)];
order.Qty += _rnd.Next(0, 8) - 4;
}
}

Right then, here goes....
This is exactly the kind of thing you want to use data-binding for. You can try and do things manually if you like, but your code will quickly become very messy if you do. WPF lets you do things the old-school way (i.e. similar to WinForms et al) but that was really to facilitate porting of legacy code. I won't go into too much detail about MVVM (plenty of info on the net about it), but you can get started by using NuGet to add MVVMLightLibs or some other MVVM framework to your project and then you assign your main window a view model by doing something like this:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.DataContext = new MainViewModel();
}
}
So now it's time for the view model itself, which is a model of the data structures that you want your view to display:
public class MainViewModel : ViewModelBase
{
public ObservableCollection<PriceLevel> PriceLevels { get; } = new ObservableCollection<PriceLevel>
{
new PriceLevel(110.98, new int[]{ }, new int[]{ }),
new PriceLevel(110.97, new int[]{ }, new int[]{ }),
new PriceLevel(110.96, new int[]{ }, new int[]{ }),
new PriceLevel(110.95, new int[]{ }, new int[]{ 5 }),
new PriceLevel(110.94, new int[]{ }, new int[]{ 3, 8 }),
new PriceLevel(110.93, new int[]{ 8, 3, 5, }, new int[]{ }),
new PriceLevel(110.92, new int[]{ 3 }, new int[]{ }),
new PriceLevel(110.91, new int[]{ }, new int[]{ }),
};
}
public class PriceLevel
{
public double Price { get; }
public ObservableCollection<int> BuyOrders { get; }
public ObservableCollection<int> SellOrders { get; }
public PriceLevel(double price, IEnumerable<int> buyOrders, IEnumerable<int> sellOrders)
{
this.Price = price;
this.BuyOrders = new ObservableCollection<int>(buyOrders);
this.SellOrders = new ObservableCollection<int>(sellOrders);
}
}
If you don't already know, ObservableCollection is very similar to list but it propegrates change notification, so when you make your view display the data in it your GUI will update automatically whenever the list changes. This MainViewModel class contains an ObservableCollection of type PriceLevel, and each PriceLevel contains the price and the lists of buy and sell orders. This means you'll be able to add and remove price points, and also add and remove the orders in the price points, and your front-end will reflect those changes.
So on to the front end itself:
<Window.Resources>
<!-- Style to display order list as horizontal list of red rectangles -->
<Style x:Key="OrderListStyle" TargetType="{x:Type ItemsControl}">
<!-- Set ItemsPanel to a horizontal StackPanel -->
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
<!-- Display each item in the order list as a red rectangle and scale x by 8*size -->
<Setter Property="ItemTemplate">
<Setter.Value>
<DataTemplate>
<Border BorderBrush="Black" BorderThickness="1" Margin="5" >
<Rectangle Width="{Binding}" Height="20" Fill="Red">
<Rectangle.LayoutTransform>
<ScaleTransform ScaleX="8" ScaleY="1" />
</Rectangle.LayoutTransform>
</Rectangle>
</Border>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
<!-- Style to make Price cells vertically aligned -->
<Style TargetType="{x:Type DataGridCell}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DataGridCell}">
<Grid Background="{TemplateBinding Background}">
<ContentPresenter VerticalAlignment="Center" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<!-- This style centers the column's header text -->
<Style TargetType="DataGridColumnHeader">
<Setter Property="HorizontalContentAlignment" Value="Center" />
</Style>
</Window.Resources>
<!-- This datagrid displays the main list of PriceLevels -->
<DataGrid ItemsSource="{Binding PriceLevels}" AutoGenerateColumns="False" IsReadOnly="True"
CanUserAddRows="False" CanUserDeleteRows="False" CanUserReorderColumns="False" CanUserResizeColumns="False"
CanUserResizeRows="False" CanUserSortColumns="False" RowHeight="30">
<DataGrid.Columns>
<!-- The buy orders column -->
<DataGridTemplateColumn Header="Buy orders" Width="*">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ItemsControl ItemsSource="{Binding BuyOrders}" Style="{StaticResource OrderListStyle}" HorizontalAlignment="Right" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<!-- The price column -->
<DataGridTextColumn Header="Price" Width="Auto" Binding="{Binding Price}" />
<!-- The sell orders column -->
<DataGridTemplateColumn Header="Sell Orders" Width="*">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ItemsControl ItemsSource="{Binding SellOrders}" Style="{StaticResource OrderListStyle}" HorizontalAlignment="Left" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
Looks a bit full-on, but if you break it down into sections it's actually pretty straightforward. The main different between this and what you've been trying to do is that I'm using a DataGrid. This is basically a Grid control that's had extra functionality added to make it respond dynamically to data that it's been bound to. It also has a lot of extra stuff we dont' need (editing, column resize/reordering etc) so I've turned all that off. The DataGrid binds to PriceLevels in the view model, so it will display a vertical list showing each one. I've then explicitly declared the 3 columns you're after. The middle one is easy, it's just text, so DataGridTextColumn will, do the job. The other two are horizontal arrays of rectangles, so I've used DataGridTemplateColumn which allows me to customize exactly how they look. This customization is mostly done in the OrderListStyle at the very top of the XAML which sets ItemsPanel to a horizontal StackPanel and sets ItemTemplate to a rectangle. There's also a bit of XAML in there to scale the rectangle by a constant, according to the value of the integer it's displaying in the order list.
Here's the result:
I know the XAML might seem a little full-on, but keep in mind this is now fully data-bound to that view model and it will automatically update in response to changes. This little bit of extra work at the start results in MUCH cleaner update code which is also easier to test and debug.
Hope this is what you're after, if you have any questions let me know and we can take it into chat.
UPDATE: If you want to see the dynamic update in action then add this to your main view model's constructor, it just adds and removes orders randomly:
public MainViewModel()
{
var rng = new Random();
var timer = new DispatcherTimer();
timer.Interval = TimeSpan.FromSeconds(0.1);
timer.Tick += (s, e) =>
{
var row = this.PriceLevels[rng.Next(this.PriceLevels.Count())]; // get random row
switch (rng.Next(4))
{
case 0: row.BuyOrders.Add(1 + rng.Next(5)); break;
case 1: row.SellOrders.Add(1 + rng.Next(5)); break;
case 2: if (row.BuyOrders.Count() > 0) row.BuyOrders.RemoveAt(rng.Next(row.BuyOrders.Count())); break;
case 3: if (row.SellOrders.Count() > 0) row.SellOrders.RemoveAt(rng.Next(row.SellOrders.Count())); break;
}
};
timer.Start();
}

UWP update a itemscontrol with an array that keeps updating

I have an array that keeps changing its values, because of this I want to have the apps UI refreshing every time the array's values do. I have this bound with an itemsControl. I can show the first array's values but then I can't update them I have tried .items.Clear() but its not working. Here are snippets of the .xaml and the xaml.cs. I actually took the code of the .xaml from a question from this site.
.xaml
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
<TextBox Text="Testing" IsReadOnly="True"></TextBox>
<ItemsControl x:Name="itemsControl"
ItemsSource="{Binding itemsControl}"
FontSize="24">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid Width="Auto"
Margin="0 12"
HorizontalAlignment="Center">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<StackPanel Grid.Column="0"
Grid.Row="0"
Orientation="Horizontal">
<TextBlock Name="txtblk0" Text="{Binding}" />
</StackPanel>
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
.xaml.cs
String c = (new String(cArray));
string[] arr = null;
string[] data = null;
if (c != null)
{
arr = c.Split('\n');
if (arr.Length > 0)
{
data = arr[0].Split(',');
}
}
for(int index = 0; index < 4; index++)
{
itemsControl.Items.Add(float.Parse(data[index]));
}
itemsControl.Clear();
If anyone has an idea of how I can do this I will be very grateful, thanks in advance and I will try to answer any questions as soon as possible!

What you're missing is an understanding of how bindings are triggered to update.
The INotifyPropertyChanged interface contains a method (PropertyChanged) and when called and passed the name of a property will tell the binding system that the property has changed and the binding should be updated.
INotifyCollectionChanged is the equivalent for collections, and communicates when a collection has changed. i.e. something added, removed, or the list cleared.
ObservableCollection<T> contains an implementation of INotifyCollectionChanged that makes it easy to work with lists, collections, etc. that change.
If you used an ObservableCollection<float> instead of an array you'd be able to modify the list and have the UI updated to reflect this easily.
As a starter, see the following which demonstrates how easy it is to use an ObservableCollection.
XAML:
<StackPanel>
<Button Click="Button_Click">add an item</Button>
<ItemsControl ItemsSource="{Binding Items}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
code behind;
public MainPage()
{
this.InitializeComponent();
// Initialize the property
this.Items = new ObservableCollection<string>();
// Use self as datacontext (but would normally use a separate viewmodel)
this.DataContext = this;
}
private void Button_Click(object sender, RoutedEventArgs e)
{
// add a new item to the UI
this.Items.Add(DateTime.Now.ToString());
}
// The "collection" that is shown in the UI
public ObservableCollection<string> Items { get; set; }

Error Dictionary Item 'DataTemplate' must have a Key attribute while set x:DataType="BitmapImage"

I'm trying to implement sample Universal Windows Platform Application for displaying Number of images in a Grid,when i frame images sources into Item-panel then build the solution getting this error "Error Dictionary Item 'Data Template' must have a Key attribute"
Please any one suggest some thing or help me.
public ObservableCollection<BitmapImage> ImgList = new ObservableCollection<BitmapImage>();
for (int i = 1; i < 15; i++)
{
var image = new Image
{
Source = new BitmapImage(
new Uri(
"https://canaryappstorage.blob.core.windows.net/dummy-container/food"+i+"_tn.jpg"))
};
var bitmapImage = new BitmapImage();
ImgList.Add(image.Source as BitmapImage);
image.Source = null;
}
<ItemsControl ItemsSource="{Binding ImgList2}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.Resources>
<DataTemplate x:DataType="BitmapImage">
<StackPanel Orientation="Horizontal">
<Image Width="200"
Height="100"
Source="{x:Bind }"
Stretch="UniformToFill" />
</StackPanel>
</DataTemplate>
</ItemsControl.Resources>
</ItemsControl>

You are defining the DataTemplate in ItemsControl.Resources. To make it work as a template for your items, you have to declare it in ItemsControl.ItemTemplate.

Binding Itemscontrol in Listbox

I want to binding my itemscontrol in listbox, but it doesn't work. I want to add some FrameworkElement to Listbox with stack style.
Here is my XAML code:
<ListBox x:Name="listThemes">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Margin="5">
<Grid Grid.Column="1">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<TextBlock Text="{Binding Title}" FontWeight="Bold" />
<StackPanel Grid.Row="1" >
<ItemsControl Width="Auto"
Height="Auto"
ItemsSource="{Binding ElementName=listThemes, Path=Items}">
</ItemsControl>
</StackPanel>
</Grid>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I don't know how to binding ItemsControl inside ListBox. I try put out the Binding ElementName of ItemsControl but it's always crashes. If the ElementName is page name, it not work.
Testing Class :
public class Testing
{
public string Title { get; set; }
public ObservableCollection<FrameworkElement> Items { get; set; }
}
C# Code :
observableCollection = new ObservableCollection<FrameworkElement>();
for (int i = 0; i < 3; i++)
{
observableCollection.Add(new Button { Content = i.ToString() });
observableCollection.Add(new Canvas
{
Background = new ImageBrush()
{
ImageSource = new BitmapImage(new Uri(#"Assets/ApplicationIcon.png", UriKind.Relative)),
Stretch = System.Windows.Media.Stretch.Fill
},
Height = 100,
Width = 100
});
}
List<Testing> list = new List<Testing>();
for (int i = 0; i < 3; i++)
{
Testing test = new Testing();
test.Title = "Testing";
test.Items = observableCollection;
list.Add(test);
}
listThemes.ItemsSource = list;

First, it crashes because you bind the same elements on three different item. One framework element can't be attach under two different control. So you should place your ObservableCollection in your List<Testing> creating process.
Second, you should set a DataContext to your listThemes control, so its items can find the right data path to bind and then you could remove the ElementName.
Try these code.
List<Testing> list = new List<Testing>();
for (int i = 0; i < 3; i++)
{
Testing test = new Testing();
test.Title = "Testing";
var observableCollection = new ObservableCollection<FrameworkElement>();
for (int j = 0; i < 3; i++)
{
observableCollection.Add(new Button { Content = j.ToString() });
observableCollection.Add(new Canvas
{
Background = new ImageBrush()
{
ImageSource = new BitmapImage(new Uri(#"Assets/ApplicationIcon.png", UriKind.Relative)),
Stretch = System.Windows.Media.Stretch.Fill
},
Height = 100,
Width = 100
});
}
test.Items = observableCollection;
list.Add(test);
}
listThemes.DataContext = list;
listThemes.ItemsSource = list;
Third, I don't think it is a good way to bind your FrameworkElement directly to an ItemsControl. It just look weird.
Update:
If you want to generate different types of items, you can use DataTemplateSelector. Because you already parse the forum data into different type, so please check this post:
How to Control the DataTemplateSelector in Windows Store Apps
It explains how to use DataTemplateSelector to display different type of data.

Why is your inner collection of type FrameworkElement?
Create a custom type for it and set an ItemTemplate for your inner ItemsControl.
<DataTemplate x:Key=NestedItemsTemplate>
....
</DataTemplate>
<ListBox x:Name="listThemes"
ItemsSource="{Binding TestItems}">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Margin="5">
<Grid Grid.Column="1">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<TextBlock Text="{Binding Title}" FontWeight="Bold" />
<StackPanel Grid.Row="1" >
<ItemsControl
Width="Auto" Height="Auto"
ItemsSource="{Binding ElementName=listThemes, Path=Items}"
ItemTemplate="{StaticResource NestedItemsTemplate}">
</ItemsControl>
</StackPanel>
</Grid>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>

How to bind data to a ListBox in a ControlTemplate?

What I am trying to do is to create some sort of "rooms"(like a chat group, a sharing center or whatever you want). All the room are created the same way, but each one of them contains different informations. Each of these rooms is contained in a TabItem. I managed to create dynamically all the Tabitems, to give those a Grid and a Canvas. But at the moment I am facing a problem: I created a ControlTemplate Called RoomMenu that will show different buttons and, the most important, the people connected in this room in a ListBox(I retrieve those people from a WebService each time I change the selected Tabitem). But since my ListBox is in a ControlTemplate I have no idea how to access the ListBox ItemSource to bind a generic List to it. Down Below is the code used to create my rooms and their content.
Here is my room menu class:
public class RoomMenu : ContentControl
{
public RoomMenu()
{
DefaultStyleKey = typeof(RoomMenu);
}
public string Current_room_id;
public string FullName;
public string Rights;
}
And here is the ControlTemplate located in generic.xaml:
<Style TargetType="test:RoomMenu">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="test:RoomMenu">
<Grid x:Name="MenuGrid">
<Border HorizontalAlignment="Stretch" VerticalAlignment="Stretch" BorderBrush="Black" CornerRadius="2" Background="Black">
<StackPanel Orientation="Vertical">
<Border x:Name="Room_friend_border" Background="Gray" CornerRadius="4" Margin="5">
<ListBox x:Name="current_room_friends" ItemsSource="{Binding ''}" Margin="5" Height="230">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding FullName}" Height="20"/>
<TextBlock Text="{Binding Rights}" Height="20"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Border>
<Border x:Name="Room_menu" Background="Gray" CornerRadius="4" Margin="5">
<StackPanel Orientation="Vertical" Margin="10">
<Button Content="Add item" Margin="0,2,0,2"/>
<Button Content="Set changes" Margin="0,2,0,2"/>
<Button Content="Invite friend" Margin="0,2,0,2"/>
<Button Content="Rename room" Margin="0,2,0,2"/>
<Button Content="Delete room" Margin="0,2,0,2"/>
</StackPanel>
</Border>
</StackPanel>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Here is my Dictionnary Class that contains the RoomMenu:
public class Rooms : TabItem
{
public string Room_guid;
public string Room_name;
public string Primary_user_guid;
public string Room_version;
public Grid Room_grid;
public Canvas Room_canvas;
public RoomMenu Room_menu;
}
And this is when I call my ControlTemplate and Add it to my TabItem's Grid:
public void Set_rooms_interface()
{
foreach (KeyValuePair<string, Rooms> kvp in rooms_list)
{
rooms_list[kvp.Key].Room_menu = new RoomMenu();
rooms_list[kvp.Key].Room_canvas = new Canvas();
rooms_list[kvp.Key].Room_grid = new Grid();
//instance grid columns
rooms_list[kvp.Key].Room_grid.ColumnDefinitions.Add(new ColumnDefinition() {Width = new GridLength(900)});
rooms_list[kvp.Key].Room_grid.ColumnDefinitions.Add(new ColumnDefinition());
//Refreshing room canvas
rooms_list[kvp.Key].Room_canvas.Height = rooms_list[kvp.Key].Room_grid.ActualHeight;
rooms_list[kvp.Key].Room_canvas.Width = rooms_list[kvp.Key].Room_grid.ActualWidth;
rooms_list[kvp.Key].Room_canvas = refresh_canvas(kvp.Key);
Grid.SetColumn(rooms_list[kvp.Key].Room_canvas, 0);
Grid.SetColumn(rooms_list[kvp.Key].Room_menu, 1);
//Add Canvas to Grid
rooms_list[kvp.Key].Room_grid.Children.Add(rooms_list[kvp.Key].Room_canvas);
rooms_list[kvp.Key].Room_grid.Children.Add(rooms_list[kvp.Key].Room_menu);
//Setting TabItem Name
rooms_list[kvp.Key].Header = rooms_list[kvp.Key].Room_name;
//Adding Grid to TabItem.Content
rooms_list[kvp.Key].Content = rooms_list[kvp.Key].Room_grid;
//Adding TabItem to TabControl
Room_tab.Items.Add(kvp.Value);
}
}
I'm sorry if the whole question is a bit long but it was the only way to explain clearly what I was trying to do. So if anyone could give me a hint or answer to do some databinding in a ControlTemplate it would greatly help me.
Thank You.

I think you started in the wrong direction when instantiating UI elements in code. The code behind should only contain one line assigning the people list to the current_room_friends DataContext.
Start with simpler examples of binding data to a ListBox like the beautiful planet example of Bea Stollnitz.