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WPF - Listview data binding to web socket data too slow

I load about 190 items from a web socket and display them in a listview but the update on the data is too slow and not in synchrony with the real data. I tried with one item and it works perfectly. Is there a more efficient way to bind the data to the ObservableCollection? Should I try with virtualization? Or any other suggestions to make the code work as expected? Here is my code
The Models:
public class WSFuturesResponse
{
public string channel { get; set; }
public string market { get; set; }
public string type { get; set; }
public WSFuturesData data { get; set; } = new WSFuturesData();
}
public class WSFuturesData
{
public double? bid { get; set; }
public double? ask { get; set; }
public double? bidSize { get; set; }
public double? askSize { get; set; }
public double? last { get; set; }
public double? time { get; set; }
}
public class Tickers
{
public string Market { get; set; }
public double? Price { get; set; }
public Tickers(string market)
{
Market = market;
}
}
public class ApiFuturesData
{
public string name { get; set; }
}
public class ApiFuturesResponse
{
public bool success { get; set; }
public List<ApiFuturesData> result { get; set; }
}
The ViewModel
public class Ticker : INotifyPropertyChanged
{
protected string url = "wss://ftx.com/ws/";
protected WebSocket _webSocketClient;
public Action OnWebSocketConnect;
public event PropertyChangedEventHandler PropertyChanged;
private WSFuturesResponse _futuresResponse;
public List<Tickers> ListTickers = new List<Tickers>();
public WSFuturesResponse FuturesResponse
{
get
{
return _futuresResponse;
}
set
{
_futuresResponse = value;
OnPropertyChanged("FuturesResponse");
// Use the dispatcher to avoid System.NotSupportedException
App.Current.Dispatcher.Invoke(delegate
{
Tickers.Clear();
foreach (var future in ListTickers)
{
if (future.Market == FuturesResponse.market)
{
future.Price = FuturesResponse.data.last;
}
Tickers.Add(future);
}
});
}
}
public ObservableCollection<Tickers> Tickers { get; set; }
private void OnPropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public Ticker()
{
Tickers = new ObservableCollection<Tickers>();
StartWebSocket();
}
public void StartWebSocket()
{
Client client = new Client("firstkey", "secondkey");
FtxRestApi api = new FtxRestApi(client);
StartConnection(this, client, api);
}
private async void StartConnection(Ticker wsApi, Client client, FtxRestApi api)
{
// get all futures data from the API
var futures = await api.GetAllFuturesAsync();
// parse the data
ApiFuturesResponse all_futures = JsonConvert.DeserializeObject<ApiFuturesResponse>(futures);
wsApi.OnWebSocketConnect += () =>
{
wsApi.SendCommand(FtxWebSocketRequestGenerator.GetAuthRequest(client));
foreach (ApiFuturesData future in all_futures.result)
{
if (future.name.Contains("PERP"))
{
// add the name to the list and use it to subscribe to the channel
ListTickers.Add(new Tickers(future.name));
wsApi.SendCommand(FtxWebSocketRequestGenerator.GetSubscribeRequest("ticker", future.name));
}
}
};
await wsApi.Connect();
}
public void WebsocketOnMessageReceive(object o, MessageReceivedEventArgs messageReceivedEventArgs)
{
FuturesResponse = JsonConvert.DeserializeObject<WSFuturesResponse>(messageReceivedEventArgs.Message);
}
And the XAML code:
<Window x:Class="FTXTradingClient.Views.TickerView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:vm="clr-namespace:FTXTradingClient.ViewModel"
xmlns:local="clr-namespace:FTXTradingClient.Views"
mc:Ignorable="d"
Title="FTX Trading Client" Height="850" Width="1200">
<Window.Resources>
<vm:Ticker x:Key="vm"/>
</Window.Resources>
<Grid DataContext="{StaticResource vm}">
<Grid.RowDefinitions>
<RowDefinition Height="20"/>
<RowDefinition Height="50"/>
<RowDefinition Height="*"/>
<RowDefinition Height="auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="40"/>
<ColumnDefinition Width="300"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<ListView Grid.Row="2"
Grid.Column="1"
ItemsSource="{Binding Tickers}">
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="0" Text="{Binding Market}"/>
<Label Grid.Column="1"/>
<TextBlock Grid.Column="2" Text="{Binding Price}"/>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</Grid>
</Window>

You could try to reset the Tickers property instead of first clearing all items in it and then add the new ones back:
public WSFuturesResponse FuturesResponse
{
get
{
return _futuresResponse;
}
set
{
_futuresResponse = value;
OnPropertyChanged("FuturesResponse");
foreach (var future in ListTickers)
{
if (future.Market == FuturesResponse.market)
{
future.Price = FuturesResponse.data.last;
}
}
// Use the dispatcher to avoid System.NotSupportedException
App.Current.Dispatcher.Invoke(delegate
{
Tickers = new ObservableCollection<Tickers>(ListTickers);
});
}
}
private ObservableCollection<Tickers> _tickers;
public ObservableCollection<Tickers> Tickers
{
get { return _tickers; }
set { _tickers = value; OnPropertyChanged("Tickers"); }
}

Grouped Collection View list not displaying, possible Binding error

I just began working with the MVVM layout and I cannot seem to display anything in my collectionView List. I believe it's my binding, unfortunately I don't really understand how I am supposed to bind a grouped list + the ViewModel. I read to bind to the path no the source, but I'm pretty sure I am doing this incorrectly. I have checked to see if I am even getting shares to load and I am, they're just not displaying.
Model -- Share
[JsonProperty("iSpottedID")]
public int ID { get; set; }
[JsonProperty("sShoppingList")]
[MaxLength(255)]
public string ShoppingName { get; set; }
[JsonProperty("dtInfoUpdate")]
[MaxLength(20)]
public string CreateDate { get; set; }
[JsonProperty("iProductID")]
public int ProductID { get; set; }
[Indexed]
[JsonProperty("sLocation")]
[MaxLength(255)]
public string LocationName { get; set; }
[JsonProperty("tvCardJson")]
public string JsonString { get; set; }
ViewModel -- SharesViewModel
public class SharesViewModel : BaseViewModel
{
#region Properties
private int _id;
public int ID
{
get { return _id; }
set
{
SetValue(ref _id, value);
OnPropertyChanged(nameof(ID));
}
}
private string _longName;
public string LongName
{
get { return _longName; }
set
{
SetValue(ref _longName, value);
OnPropertyChanged(nameof(LongName));
}
}
private string _date;
public string CreateDate
{
get{ return _date;}
set
{
SetValue(ref _date, value);
OnPropertyChanged(nameof(CreateDate));
}
}
private int _prodID;
public int ProductID
{
get { return _id; }
set
{
SetValue(ref _prodID, value);
OnPropertyChanged(nameof(ProductID));
}
}
private string _json;
public string JsonString
{
get { return _json; }
set
{
SetValue(ref _json, value);
OnPropertyChanged(nameof(JsonString));
}
}
private string _location;
public string LocationName
{
get { return _location; }
set
{
SetValue(ref _location, value);
OnPropertyChanged(nameof(LocationName));
}
}
//ADD-ONS
public string Address
{
get
{
if (!string.IsNullOrEmpty(JsonString))
{
var jsonDict = JsonConvert.DeserializeObject<Dictionary<string, string>>(JsonString);
if (jsonDict.ContainsKey("address"))
if (jsonDict["address"] != "")
return jsonDict["address"];
}
return null;
}
}
private ImageSource _imageLink;
public ImageSource ImageLink
{
get
{
if(ProductID != 0)
{
...
return ImageSource.FromUri(link);
}
return null;
}
}
#endregion
public SharesViewModel(){}
public SharesViewModel(Share share)
{
ID = share.ID;
ProductID = share.ProductID;
JsonString = share.JsonString;
CreateDate = share.CreateDate;
LocationName = share.LocationName;
}
List View Model -- SharesListViewlModel
public class SharesListViewModel : BaseViewModel
{
private SharesViewModel _selectedShare;
private bool _isDataLoaded;
//grouped list
public ObservableCollection<LocationSpotGroups<string, SharesViewModel>> Shares { get; set; }
...
public ICommand OpenMoreSharesCommand { get; private set; }
public ICommand LoadDataCommand { get; private set; }
public SharesListViewModel(Position NW , Position SE)
{
_nw = NW;
_se = SE;
LoadDataCommand = new Command(async () => await LoadData());
OpenMoreSharesCommand = new Command<SharesViewModel>(async (share) => await OpenMoreShares(share));
public ObservableCollection<SharesViewModel> sList { get; set; }
= new ObservableCollection<SharesViewModel>();
}
private async Task LoadData()
{
if (_isDataLoaded)
return;
var list = await _connection.GetAllRegionShares(_nw, _se);
foreach (var spot in list)
{
sList.Add(new SharesViewModel(spot));
}
var sorted = from item in sList
orderby item.LocationName
group item by item.LocationName into itemGroup
select new LocationSpotGroups<string, SharesViewModel>(itemGroup.Key, itemGroup);
Shares = new ObservableCollection<LocationSpotGroups<string, SharesViewModel>>(sorted);
}
LocationSpotGroups
public class LocationSpotGroups<K, T> : ObservableCollection<T>
{
public K GroupKey { get; set; }
public IEnumerable<T> GroupedItem { get; set; }
public LocationSpotGroups(K key, IEnumerable<T> shares)
{
GroupKey = key;
GroupedItem = shares;
foreach (var item in shares)
{
this.Items.Add(item);
}
}
}
SharesPage XAML
<CollectionView x:Name="CollectionList"
VerticalOptions="FillAndExpand"
ItemsSource="{Binding Shares}"
IsGrouped="True">
<!--HEADER-->
<CollectionView.GroupHeaderTemplate>
<DataTemplate>
<StackLayout Orientation="Horizontal"
Padding="5"
BackgroundColor="#f7f7fb">
<Label x:Name="labelname"
Text="{Binding GroupKey}"
HorizontalOptions="Start"
VerticalOptions="Center"
TextColor="gray" />
</StackLayout>
</DataTemplate>
</CollectionView.GroupHeaderTemplate>
<CollectionView.ItemsLayout>
<GridItemsLayout Orientation="Vertical" Span="2" />
</CollectionView.ItemsLayout>
<!--BODY-->
<CollectionView.ItemTemplate>
<DataTemplate>
<Grid Padding="5" Margin="8">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="50" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<ImageButton Source="{Binding ImageLink}"
WidthRequest="150"
HeightRequest="150"
Grid.ColumnSpan="2"
CornerRadius="15"
Aspect="AspectFill"
Grid.Row="0"
Grid.Column="0"/>
<Label Text="{Binding ShoppingName}"
Grid.Row="1"
Grid.Column="0"/>
<Label Text="More"
Grid.Row="1"
Grid.Column="1"
HorizontalTextAlignment="End"/>
<Label Text="{Binding CreateDate}"
Grid.Row="2"
Grid.Column="0"/>
</Grid>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
SharesPage CS
public SharesPage( Position NW, Position SE )
{
InitializeComponent();
ViewModel = new SharesListViewModel(NW, SE);
}
public SharesListViewModel ViewModel
{
get { return BindingContext as SharesListViewModel; }
set { BindingContext = value; }
}
protected override void OnAppearing()
{
ViewModel.LoadDataCommand.Execute(null);
base.OnAppearing();
}

Loading the data in the constructor works if the data is not a lot, which is wasn't in my case. Everything loads perfectly.

ObservableCollection not showing any items on ListView

I am trying to bind a ObservableCollection on a ListView ItemsSource but it doesn't show anything to me, tried binding inside code, on the xaml..
public partial class ReadPage : ContentPage
{
private CarregarClientes _CClientes = new CarregarClientes();
private MySQLCon _db = new MySQLCon();
private MySQLConOverloads _over = new MySQLConOverloads();
private MySQLiteCon _dbSqLiteCon = new MySQLiteCon();
private MySQLiteConOverloads _oversqlite = new MySQLiteConOverloads();
//MY OBSERVABLECOLLECTION DEFINITION -----------------------------
public ObservableCollection<Clientes> _ClientesList { get; set; }
private string _tabela = "Clientes";
public ReadPage()
{
InitializeComponent();
backBtn.Clicked += async (s, o) => await Navigation.PopModalAsync();
//Method used to populate the ObservableCollection (_ClientesList);
PopularObservableCollection();
}
I am defining the ObservableCollection inside my ReadPage class, then populating it with a method called PopularObservableCollection.
public void PopularObservableCollection()
{
_ClientesList = new ObservableCollection<Clientes>();
int quantidadeDados = _CClientes.CNumeroItems() -1;
List<string> id = _CClientes.Cid();
List<string> debito = _CClientes.CDebito();
List<string> endereco = _CClientes.CEndereco();
List<string> nome = _CClientes.CNome();
List<string> observacao = _CClientes.CObservacao();
List<string> saldo = _CClientes.CSaldo();
List<string> telefone = _CClientes.CTelefone();
for (int i = 0; i <= quantidadeDados; i++)
{
_ClientesList.Add(new Clientes
{
id = id[i],
Debito = debito[i],
Endereco = endereco[i],
Nome = nome[i],
Observacao = observacao[i],
Saldo = saldo[i],
Telefone = telefone[i]
});
}
}
Clientes.cs:
public class Clientes : BindableObject
{
public string id { get; set; }
public string Nome { get; set; }
public string Endereco { get; set; }
public string Telefone { get; set; }
public string Debito { get; set; }
public string Saldo { get; set; }
public string Observacao { get; set; }
}
XAML:
<ListView
BindingContext="{Binding Source={x:Reference MyPage}, Path=.}"
x:Name="readListView"
BackgroundColor="PaleVioletRed"
HasUnevenRows="True"
CachingStrategy="RecycleElement"
HorizontalOptions="FillAndExpand"
ItemsSource="{Binding _ClientesList}"
VerticalOptions="FillAndExpand"
ItemTapped="ReadListView_OnItemTapped">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid>
<Label Text="Id:" Grid.Row="0"/>
<Label Text="{Binding id}" Grid.Row="0" Margin="10,0,0,0"/>
<Label Text="{Binding Nome}" Grid.Row="1" />
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>

WPF, Caliburn.Micro and Dapper ComboBoxes

I am just new to WPF, Caliburn.Micro and Dapper. I have three combo boxes: the first one is for the region, the second one is for the provinces in the particular selected region and the third one are the cities in the particular selected province. What I want to achieve is that when I selected a particular region it will display all the provinces in that region, the same with the province combo box, when selected it will display all the cities associated with that province. Can this be done in a single method? Here is my code so far.
DataAccess
public List<RegionModel> GetRegion_All()
{
List<RegionModel> output;
using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(GlobalConfig.CnnString(db)))
{
output = connection.Query<RegionModel>("dbo.spRegion_GetAll").ToList();
var p = new DynamicParameters();
foreach (RegionModel region in output)
{
p = new DynamicParameters();
p.Add("#RegionId", region.Id);
region.Provinces = connection.Query<ProvinceModel>("dbo.spProvince_ByRegion", p, commandType: CommandType.StoredProcedure).ToList();
foreach (ProvinceModel province in region.Provinces)
{
p = new DynamicParameters();
p.Add("#ProvinceId", province.Id);
region.Cities = connection.Query<CityModel>("dbo.spCity_ByProvince", p, commandType: CommandType.StoredProcedure).ToList();
}
}
}
return output;
}
Models
public class RegionModel
{
public int Id { get; set; }
public string Region { get; set; }
public string RegionName { get; set; }
public List<ProvinceModel> Provinces { get; set; } = new List<ProvinceModel>();
public List<CityModel> Cities { get; set; } = new List<CityModel>();
public List<BarangayModel> Barangays { get; set; } = new List<BarangayModel>();
}
public class ProvinceModel
{
public int Id { get; set; }
public string Province { get; set; }
public int RegionId { get; set; }
}
public class CityModel
{
public int Id { get; set; }
public string City { get; set; }
public int ProvinceId { get; set; }
public int ZipCode { get; set; }
}
ViewModel
public class ShellViewModel : Screen
{
private BindableCollection<RegionModel> _region;
private RegionModel _selectedRegion;
private ProvinceModel _selectedProvince;
public ShellViewModel()
{
GlobalConfig.InitializeConnections(DatabaseType.Sql);
Region = new BindableCollection<RegionModel>(GlobalConfig.Connection.GetRegion_All());
}
public BindableCollection<RegionModel> Region
{
get { return _region; }
set
{
_region = value;
}
}
public RegionModel SelectedRegion
{
get { return _selectedRegion; }
set
{
_selectedRegion = value;
NotifyOfPropertyChange(() => SelectedRegion);
}
}
public ProvinceModel SelectedProvince
{
get { return _selectedProvince; }
set
{
_selectedProvince = value;
NotifyOfPropertyChange(() => SelectedRegion);
}
}
View
<Window x:Class="WPFUI.Views.ShellView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WPFUI.Views"
mc:Ignorable="d" WindowStartupLocation="CenterScreen"
Title="ShellView" Height="450" Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition Height="auto" />
<RowDefinition Height="auto" />
<RowDefinition Height="auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<ComboBox Grid.Row="0" x:Name="Region" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding RegionName}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<ComboBox Grid.Row="1" x:Name="SelectedRegion_Provinces" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Province}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<ComboBox Grid.Row="2" x:Name="SelectedRegion_Cities" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding City}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Most of my codes ideas are from the tutorials I found in youtube, since references and materials for WPF, Caliburn.Micro and Dapper are very hard to find. Please be patient with my code :)

You have lot of mistake and you dont use the power of Caliburn
The wpf definition:
with Caliburn if you give name Region for combobox, it waits a bindableCollection with same name (Region) and SelectedItem is named SelectedRegion
(see name convention with Caliburn). So i choose Region, Province & City
In the different models i have renamed all strings RegionName, ProvinceName and CityName.
<ComboBox Grid.Row="0" x:Name="Region" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding RegionName}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<ComboBox Grid.Row="1" x:Name="Province" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding ProvinceName}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<ComboBox Grid.Row="2" x:Name="City" >
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding CityName}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
then, i have modified your class definition:
public class RegionModel:PropertyChangedBase
{
public int Id { get; set; }
public string Region { get; set; }
public string RegionName { get; set; }
// each Region has its Provinces
public List<ProvinceModel> Provinces { get; set; } = new List<ProvinceModel>();
}
public class ProvinceModel:PropertyChangedBase
{
public int Id { get; set; }
public string ProvinceName { get; set; }
public int RegionId { get; set; }
// each Province has its Cities
public List<CityModel> Cities { get; set; } = new List<CityModel>();
}
public class CityModel:PropertyChangedBase
{
public int Id { get; set; }
public string CityName { get; set; }
public int ProvinceId { get; set; }
public int ZipCode { get; set; }
}
Then in ViewModel i add the different BindableCollection Region, Province & City dont forget to add
using Caliburn.Micro;
in the using definion. Then Add the Selected Definition
public class ShellViewModel : Screen
{
private RegionModel selectedRegion;
private ProvinceModel selectedProvince;
private CityModel selectedCity;
private BindableCollection<RegionModel> _region;
private BindableCollection<ProvinceModel> _province;
private BindableCollection<CityModel> _city;
public BindableCollection<RegionModel> Region
{
get { return _region; }
set
{
_region = value;
NotifyOfPropertyChange(() => Region);
}
}
public BindableCollection<ProvinceModel> Province
{
get { return _province; }
set
{
_province = value;
NotifyOfPropertyChange(() => Province);
}
}
public BindableCollection<CityModel> City
{
get { return _city; }
set
{
_city = value;
NotifyOfPropertyChange(() => City);
}
}
public RegionModel SelectedRegion
{
get { return selectedRegion; }
set
{
selectedRegion = value;
NotifyOfPropertyChange(() => SelectedRegion);
Province.Clear();
Province.AddRange(selectedRegion.Provinces);
NotifyOfPropertyChange(() => Province);
}
}
public ProvinceModel SelectedProvince
{
get { return selectedProvince; }
set
{
selectedProvince = value;
NotifyOfPropertyChange(() => SelectedProvince);
City.Clear();
City.AddRange(selectedProvince.Cities);
NotifyOfPropertyChange(() => City);
}
}
public CityModel SelectedCity
{
get { return selectedCity; }
set
{
selectedCity = value;
NotifyOfPropertyChange(() => SelectedCity);
}
}
public ShellViewModel()
{
// to DO INITIALIZE Regions
//
Province = new BindableCollection<ProvinceModel>();
City = new BindableCollection<CityModel>();
Region = new BindableCollection<RegionModel>(Regions);
}
and you have a functional sample
Each time you select a region, the associated provinces are loaded and same thing if you select a province for the associated Cities

Refresh WPF label

I'm trying to dynamically refresh the label that shows the current amount of space remaining but unfortunately the number doesn't refresh. Do you have any idea how to solve my problem?
C#
private void ReqDescText_Changed(object sender, TextChangedEventArgs e)
{
Counter ReqDescText_Counter = new Counter(ReqDescText, ReqDescLabelLength);
}
Class
public class Counter
{
public TextBox InputTextbox { get; set; }
public Label CounterLabel { get; set; }
public Counter(TextBox InputTextbox, Label CounterLabel)
{
int NB;
TextBox textBox = new TextBox();
var tempText = textBox.Text;
NB = (InputTextbox.MaxLength - tempText.Length);
CounterNumber counterNumber = new CounterNumber { Number = NB.ToString() };
CounterLabel.Content = counterNumber;
if (NB == 0)
{
CounterLabel.Foreground = new SolidColorBrush(Colors.Red);
}
}
class CounterNumber
{
public string Number { get; set; }
public override string ToString()
{
return "[" + Number + "]";
}
}
}
WPF
<Label x:Name ="ReqDescLabel" Content="Description" Grid.Row="1" Margin="5,5,0,5" Grid.Column="0"/>
<Label Name="ReqDescLabelLength" FontSize="10" Grid.Row="1" Grid.Column="1" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="0,6"/>
<TextBox x:Name ="ReqDescText" Padding="3" Grid.Row="1" Margin="0,5,0,5" Grid.Column="2" TextWrapping="Wrap" SpellCheck.IsEnabled="True" MaxLength="250" TextChanged="ReqDescText_Changed" ScrollViewer.VerticalScrollBarVisibility="Auto" ScrollViewer.CanContentScroll="True"/>
How it's looks like

Problem solved. My mistake.
I did't take the current length of the text.
public class Counter
{
public TextBox InputTextbox { get; set; }
public Label CounterLabel { get; set; }
public Counter(TextBox InputTextbox, Label CounterLabel)
{
int NB;
var tempText = InputTextbox.Text;
NB = (InputTextbox.MaxLength - tempText.Length);
CounterNumber counterNumber = new CounterNumber { Number = NB.ToString() };
CounterLabel.Content = counterNumber;
if (NB == 0)
{
CounterLabel.Foreground = new SolidColorBrush(Colors.Red);
}
}
class CounterNumber
{
public string Number { get; set; }
public override string ToString()
{
return "[" + Number + "]";
}
}
}