Override combobox enter key.

[Quetzalcoatl2435]

The default enter key behaviour for combobox in avalonia 11 is set to open the dropdown list. How can I override this to do something else?

[workgroupengineering]

public class MyComboBox:ComboBox
{
 
  protected override Type StyleKeyOverride => typeof(ComboBox); // for reuse the style

  protected override void OnKeyDown(KeyEventArgs e)
  {
      // Your logic
  }
}

Ref.

Avalonia/src/Avalonia.Controls/ComboBox.cs

Lines 214 to 266 in 143399f

	protected override void OnKeyDown(KeyEventArgs e)
	{
	base.OnKeyDown(e);
	if (e.Handled)
	return;
	if ((e.Key == Key.F4 && e.KeyModifiers.HasAllFlags(KeyModifiers.Alt) == false) ||
	((e.Key == Key.Down || e.Key == Key.Up) && e.KeyModifiers.HasAllFlags(KeyModifiers.Alt)))
	{
	SetCurrentValue(IsDropDownOpenProperty, !IsDropDownOpen);
	e.Handled = true;
	}
	else if (IsDropDownOpen && e.Key == Key.Escape)
	{
	SetCurrentValue(IsDropDownOpenProperty, false);
	e.Handled = true;
	}
	else if (!IsDropDownOpen && (e.Key == Key.Enter || e.Key == Key.Space))
	{
	SetCurrentValue(IsDropDownOpenProperty, true);
	e.Handled = true;
	}
	else if (IsDropDownOpen && (e.Key == Key.Enter || e.Key == Key.Space))
	{
	SelectFocusedItem();
	SetCurrentValue(IsDropDownOpenProperty, false);
	e.Handled = true;
	}
	// Ignore key buttons, if they are used for XY focus.
	else if (!IsDropDownOpen
	&& !XYFocusHelpers.IsAllowedXYNavigationMode(this, e.KeyDeviceType))
	{
	if (e.Key == Key.Down)
	{
	e.Handled = SelectNext();
	}
	else if (e.Key == Key.Up)
	{
	e.Handled = SelectPrevious();
	}
	}
	// This part of code is needed just to acquire initial focus, subsequent focus navigation will be done by ItemsControl.
	else if (IsDropDownOpen && SelectedIndex < 0 && ItemCount > 0 &&
	(e.Key == Key.Up || e.Key == Key.Down) && IsFocused == true)
	{
	var firstChild = Presenter?.Panel?.Children.FirstOrDefault(c => CanFocus(c));
	if (firstChild != null)
	{
	e.Handled = firstChild.Focus(NavigationMethod.Directional);
	}
	}
	}

[maxkatz6]

You also can handle KeyDown event with Tunnel strategy.

[Quetzalcoatl2435]

public class MyComboBox:ComboBox
{
 
  protected override Type StyleKeyOverride => typeof(ComboBox); // for reuse the style

  protected override void OnKeyDown(KeyEventArgs e)
  {
      // Your logic
  }
}

Ref.

Avalonia/src/Avalonia.Controls/ComboBox.cs

Lines 214 to 266 in 143399f

	protected override void OnKeyDown(KeyEventArgs e)
	{
	base.OnKeyDown(e);
	if (e.Handled)
	return;
	if ((e.Key == Key.F4 && e.KeyModifiers.HasAllFlags(KeyModifiers.Alt) == false) ||
	((e.Key == Key.Down || e.Key == Key.Up) && e.KeyModifiers.HasAllFlags(KeyModifiers.Alt)))
	{
	SetCurrentValue(IsDropDownOpenProperty, !IsDropDownOpen);
	e.Handled = true;
	}
	else if (IsDropDownOpen && e.Key == Key.Escape)
	{
	SetCurrentValue(IsDropDownOpenProperty, false);
	e.Handled = true;
	}
	else if (!IsDropDownOpen && (e.Key == Key.Enter || e.Key == Key.Space))
	{
	SetCurrentValue(IsDropDownOpenProperty, true);
	e.Handled = true;
	}
	else if (IsDropDownOpen && (e.Key == Key.Enter || e.Key == Key.Space))
	{
	SelectFocusedItem();
	SetCurrentValue(IsDropDownOpenProperty, false);
	e.Handled = true;
	}
	// Ignore key buttons, if they are used for XY focus.
	else if (!IsDropDownOpen
	&& !XYFocusHelpers.IsAllowedXYNavigationMode(this, e.KeyDeviceType))
	{
	if (e.Key == Key.Down)
	{
	e.Handled = SelectNext();
	}
	else if (e.Key == Key.Up)
	{
	e.Handled = SelectPrevious();
	}
	}
	// This part of code is needed just to acquire initial focus, subsequent focus navigation will be done by ItemsControl.
	else if (IsDropDownOpen && SelectedIndex < 0 && ItemCount > 0 &&
	(e.Key == Key.Up || e.Key == Key.Down) && IsFocused == true)
	{
	var firstChild = Presenter?.Panel?.Children.FirstOrDefault(c => CanFocus(c));
	if (firstChild != null)
	{
	e.Handled = firstChild.Focus(NavigationMethod.Directional);
	}
	}
	}

Custom controls went completely over my head. My mind must have blanked out for a moment there. :D

public class CustomComboBox : ComboBox
{
    protected override Type StyleKeyOverride => typeof(ComboBox);
    protected override void OnKeyDown(KeyEventArgs e)
    {
        if (IsDropDownOpen || e.Key != Key.Enter)
            base.OnKeyDown(e);
    }
}

That did it for me. Thanks for the suggestion.