UpdateSourceTrigger=PropertyChanged not working for DataGridTextColumn?

[c4rlosmarin]

I'm trying to apply a binding for my datagrid so that I can capture the change to the cells as it happens, but for some reason, I can only get to trigger the PropertyChanged event after the cell loses its focus. The same works flawlessly with a regular Textbox, meaning that the OnNameChanged and OnNameChanging events are triggered as soon as the key is down. I was able to properly make it work by adding a custom column with a Textbox in it, however everything regarding tab navigation among all the cells in the DataGrid became really cumbersome after taking that approach.

What am I missing?

`

<Grid x:Name="ContentArea">
    <TextBox Text="{x:Bind ViewModel.Name, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
    
    <controls:DataGrid AutoGenerateColumns="False" Margin="0,50" ItemsSource="{x:Bind ViewModel.Parameters, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
        <controls:DataGrid.Columns>
            <controls:DataGridCheckBoxColumn Header="" Width="40" Binding="{Binding IsEnabled, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" CanUserResize="False"/>
            <controls:DataGridTextColumn Header="Parameter" Binding="{Binding Key, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Width="*"/>
            <controls:DataGridTextColumn Header="Value" Binding="{Binding Value, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Width="*"/>
            <controls:DataGridTextColumn Header="Description" Binding="{Binding Description, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Width="*"/>
        </controls:DataGrid.Columns>
    </controls:DataGrid>
</Grid>

`

`
using App1.Helpers;
using Windows.UI.ViewManagement;
using App1.ViewModels;
namespace App1;

public sealed partial class MainWindow : WindowEx
{
public MainViewModel? ViewModel { get; }
private Microsoft.UI.Dispatching.DispatcherQueue dispatcherQueue;
private UISettings settings;

public MainWindow()
{
    InitializeComponent();

    AppWindow.SetIcon(Path.Combine(AppContext.BaseDirectory, "Assets/WindowIcon.ico"));
    Content = null;
    Title = "AppDisplayName".GetLocalized();

    // Theme change code picked from https://github.com/microsoft/WinUI-Gallery/pull/1239
    dispatcherQueue = Microsoft.UI.Dispatching.DispatcherQueue.GetForCurrentThread();
    settings = new UISettings();
    settings.ColorValuesChanged += Settings_ColorValuesChanged; // cannot use FrameworkElement.ActualThemeChanged event

    ViewModel = App.GetService<MainViewModel>();
}

// this handles updating the caption button colors correctly when indows system theme is changed
// while the app is open
private void Settings_ColorValuesChanged(UISettings sender, object args)
{
    // This calls comes off-thread, hence we will need to dispatch it to current app's thread
    dispatcherQueue.TryEnqueue(() =>
    {
        TitleBarHelper.ApplySystemThemeToCaptionButtons();
    });
}

}
`

`using System.Collections.ObjectModel;
using System.ComponentModel;
using CommunityToolkit.Mvvm.ComponentModel;

namespace App1.ViewModels;

public partial class MainViewModel : ObservableRecipient
{
[ObservableProperty]
public string name;

[ObservableProperty]
public ObservableCollection<ParameterViewModel> parameters;

public MainViewModel()
{
    Parameters = new ObservableCollection<ParameterViewModel>();
    var Parameter = new ParameterViewModel() { Key = "", Value = "", Description = ""};
    Parameter.PropertyChanged += Parameter_PropertyChanged;
    Parameter.PropertyChanging += Parameter_PropertyChanging;
    Parameters.Add(Parameter);
}

partial void OnNameChanged(string value)
{

}

partial void OnNameChanging(string value)
{

}

private void Parameter_PropertyChanged(object? sender, PropertyChangedEventArgs e)
{


}

private void Parameter_PropertyChanging(object? sender, PropertyChangingEventArgs e)
{


}    

}
public partial class ParameterViewModel : ObservableRecipient
{
[ObservableProperty]
public string key;
[ObservableProperty]
public string value;
[ObservableProperty]
public string description;
}
`