Disabled controls can be focused with the keyboard

[iminashi]

Describe the bug

Controls can be focused using the tab key even though their parent is disabled.

To Reproduce

1. Create a panel that has TextBox child.
2. Set IsEnabled to false on the panel.
3. The TextBox can be focused with the tab key and the text can be edited.

If you do this:

<StackPanel IsEnabled="False">
      <TextBox IsEnabled="False" />
      <AutoCompleteBox IsEnabled="False" />
</StackPanel>

Then the TextBox cannot be focused, but the AutoCompleteBox can.

Expected behavior

Child elements of a disabled parent should not be focusable.

Desktop

• OS: Windows 10
• Version: 0.10.7

Additional context

This worked correctly in 0.10.6.

[grokys]

Looks like a pretty major regression due to the new tab handling code ported from WPF. Will fix as soon as I'm back from vacation

[danwalmsley]

Also invisible controls!

[grokys]

This is because of a difference in how WPF and Avalonia handle IsEnabled. In WPF if reflects both the enabled state of the actual control and the effectively enabled state which comes from ancestor controls. In Avalonia that effectively enabled state is exposed on a different property: IsEffectivelyEnabled.

When I ported the tab navigation code from WPF, I didn't take that into account. Will fix.

@danwalmsley I can't repro this happening with invisible controls, do you have a repro?