Datagrid don't show elements MVVM - wpf

Question

I am trying to load a list in my datagrid when pressing the button but it does not show anything.
Do you know where the error is?
Thanks a lot
<UserControl x:Class="HiberusHubClient.View.RatesView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:HiberusHubClient.View"
mc:Ignorable="d"
x:Name="RatesViewControl"
d:DesignHeight="450" d:DesignWidth="800"
DataContext="RatesViewControlDataContext">
<Grid>
<StackPanel HorizontalAlignment = "Left">
<Button x:Name="btnUpdate" Width="100" Height="20" HorizontalAlignment="Center" Grid.Row="1" Content="Update" Command="{Binding Path=UpdateCommand}" />
<StackPanel Orientation = "Horizontal">
<DataGrid Width="200" Height="400" AutoGenerateColumns="True" ItemsSource="{Binding LstConvertRates,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" Name="lstDataGrid" />
</StackPanel>
</StackPanel>
</Grid>
</UserControl>
public partial class RatesView : UserControl
{
public RatesView()
{
InitializeComponent();
DataContext = new ConvertRatesViewModel();
}
}
ConvertRate.cs
public class ConvertRate
{
}
public class ConvertRates : INotifyPropertyChanged
{
private string currencyFrom;
private string currencyTo;
private string rate;
public string CurrencyFrom
{
get
{
return currencyFrom;
}
set
{
if (currencyFrom != value)
{
currencyFrom = value;
RaisePropertyChanged("CurrencyFrom");
}
}
}
public string CurrencyTo
{
get { return currencyTo; }
set
{
if (currencyTo != value)
{
currencyTo = value;
RaisePropertyChanged("CurrencyTo");
}
}
}
public string Rate
{
get { return rate; }
set
{
if (rate != value)
{
rate = value;
RaisePropertyChanged("Rate");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(property));
}
}
}
ConvertRatesViewModel .cs
internal class ConvertRatesViewModel : INotifyPropertyChanged
{
private ObservableCollection<ConvertRates> lstConvertRates;
public ObservableCollection<ConvertRates> LstConvertRates
{
get
{
return lstConvertRates;
}
set
{
lstConvertRates = value;
//if u want Observable Collection to get updated on edit either
RaisePropertyChanged("LstConvertRates");
}
}
public void getConvertRates()
{
HiberusHubeReference.RequestHubeRestService hiberusHubeReference = new HiberusHubeReference.RequestHubeRestService();
JavaScriptSerializer json = new JavaScriptSerializer();
string aa = json.Serialize(hiberusHubeReference.RequestRates());
ObservableCollection<ConvertRates> oMycustomclassname = Newtonsoft.Json.JsonConvert.DeserializeObject<ObservableCollection<ConvertRates>>(aa);
LstConvertRates = oMycustomclassname;
}
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(property));
}
}
private ICommand mUpdater;
public ICommand UpdateCommand
{
get
{
if (mUpdater == null)
mUpdater = new Updater();
return mUpdater;
}
set
{
mUpdater = value;
}
}
}
internal class Updater : ICommand
{
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged
{
add { CommandManager.RequerySuggested += value; }
remove { CommandManager.RequerySuggested -= value; }
}
public void Execute(object parameter)
{
ConvertRatesViewModel convertRatesViewModel = new ConvertRatesViewModel();
convertRatesViewModel.getConvertRates();
}
}

Answer 1

If you set DataContext in code behind then there is no need to set DataContext also in xaml. You can remove DataContext="RatesViewControlDataContext" from RatesView.xaml. Btw. DataContext="RatesViewControlDataContext" means DataContext property is set to string "RatesViewControlDataContext". You probably don't this.
Try to use existing implementation of ICommand interface like RelayCommand.
public class RelayCommand : ICommand
{
private readonly Predicate<object> _canExecute;
private readonly Action<object> _execute;
public RelayCommand(Predicate<object> canExecute, Action<object> execute)
{
_canExecute = canExecute;
_execute = execute;
}
public event EventHandler CanExecuteChanged
{
add => CommandManager.RequerySuggested += value;
remove => CommandManager.RequerySuggested -= value;
}
public bool CanExecute(object parameter)
{
return _canExecute(parameter);
}
public void Execute(object parameter)
{
_execute(parameter);
}
}
For your UpdateCommand you can modify the setter and create a new instance of RelayCommand. In the constructor you can specify whether the command should be executed and which method on your ConvertRatesViewModel will be called when you press btnUpdate button.
private ICommand mUpdater;
public ICommand UpdateCommand
{
get
{
if (mUpdater == null)
mUpdater = new RelayCommand(x => true, x => getConvertRates());
return mUpdater;
}
set
{
mUpdater = value;
}
}