Accessing Nested Cells in Avalonia Property Grid: Difficulty Modifying Content Below Category Children

[OmerFarukAkyapak]

Hello, I'm experiencing an issue with Avalonia Property Grid. While I can access the children underneath a selected category in the property grid, I'm unable to access the cells within these children. Specifically, I'm having difficulty accessing and modifying the cells of second-level children under a category.

We can access the cell edit of the first category in the property data grid that opens with the selected object, but if there is another cell hierarchically in this cell, I cannot access it. How do I access it?

It like Category -> Children (Expandable -like Category)-> Children (target)
I want to modified target's cell edit content.

var cellInfos = propertyGrid.GetCellInfoCache().Children;

foreach (var item in cellInfos)
{
    Debug.WriteLine(item);
    if (item.Category == "Integration")
    {
        foreach (var item2 in item.Children)
        {
            Debug.WriteLine(item2);
            if (item2.Context.DisplayName == "MQ Consumer")
            {
                // i cant access to item2's child
                item2.Context.CellEdit.Tapped += (sender, e) => ShowCollectionEditor();
                return;
            }
        }
    }

    if (item.Category == "Stores")
    {
        foreach (var item2 in item.Children)
        {
            if (item2.Context.DisplayName == "Database Store")
            {
                item2.Context.CellEdit.Tapped += (sender, e) => ShowCollectionEditor();
            }
        }

    }
}

I cant access to own button cell edit factory's button.

var topLevel = TopLevel.GetTopLevel(this);
if (topLevel is null) return;

var thisPropertyGrid = this.FindControl<PropertyGrid>("propertyGrid");


if (thisPropertyGrid.FindControl<Button>("MQTT WorkOrder Subscribers") is Button mqttButton)
{
    mqttButton.Click += (sender, e) => { Debug.WriteLine("TAPPED"); };
}

if (thisPropertyGrid.FindControl<Button>("Redis WorkOrder Subscribers") is Button redisButton)
{
    redisButton.Click += (sender, e) => { Debug.WriteLine("TAPPED"); };
}

if (thisPropertyGrid.FindControl<Button>("RabbitMQ WorkOrder Subscribers") is Button rabbitButton)
{
    rabbitButton.Click += (sender, e) => { Debug.WriteLine("TAPPED"); };
}

if (thisPropertyGrid.FindControl<Button>("Databases") is Button dbButton)
{
    dbButton.Click += (sender, e) => { Debug.WriteLine("TAPPED"); };
}

[OmerFarukAkyapak]

I solved this problem.

Firstly, create a button cell edit factory.
And button contains cell context's name. So button's name equals context's display name.

public class ButtonCellEditFactory : AbstractCellEditFactory
{
    public override Control HandleNewProperty(PropertyCellContext context)
    {
        var propertyDescriptor = context.Property;
        var target = context.Target;

        if (!IsListType(propertyDescriptor.PropertyType))
        {
            return null;
        }

        Button control = new Button
        {
            Name = context.DisplayName,
            Content = "[...]",
            Background = Brushes.LightGray,
            HorizontalAlignment = Avalonia.Layout.HorizontalAlignment.Stretch,
            VerticalAlignment = Avalonia.Layout.VerticalAlignment.Stretch,
            HorizontalContentAlignment = Avalonia.Layout.HorizontalAlignment.Center,
            VerticalContentAlignment = Avalonia.Layout.VerticalAlignment.Center
        };
        return control;
    }

    public override bool HandlePropertyChanged(PropertyCellContext context)
    {
        var propertyDescriptor = context.Property;
        var target = context.Target;
        var control = context.CellEdit;

        if (!IsListType(propertyDescriptor.PropertyType))
        {
            return false;
        }

        ValidateProperty(control, propertyDescriptor, target);

        if (control is Button button)
        {
            //button's property controls
            return true;
        }

        return false;
    }
    private bool IsListType(Type type)
    {
        return type.IsGenericType &&
               type.GetGenericTypeDefinition() == typeof(List<>);
    }
}

Then we can use the button with a special name.
We access this button with a special name using the "GetVisualDescendants()" method.
And we can do the customization we want.

public void ActivateGridCollectionButton()
{
    foreach (var control in this.GetVisualDescendants())
    {
        if (control.GetType().Name != "Button") continue;
        if (control.Name is null) continue;

        string buttonName = control.Name;
        Button button = control as Button;

        if (buttonName == "MQTT WorkOrder Subscriber" && button != null)
        {
            button.Click += (sender, e) => ShowCollectionEditor(1);
        }
        else if (buttonName == "RabbitMQ WorkOrder Subscriber" && button != null)
        {
            button.Click += (sender, e) => ShowCollectionEditor(2);
        }
        else if (buttonName == "Redis WorkOrder Subscriber" && button != null)
        {
            button.Click += (sender, e) => ShowCollectionEditor(3);
        }
        else if (buttonName == "Databases" && button != null)
        {
            button.Click += (sender, e) => ShowCollectionEditor(4);
        }
    }
}
private void UserControl_Loaded(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
{
    ActivateGridCollectionButton();
}