https://learn.microsoft.com/en-us/uwp/api/windows.ui.xaml.uielement.losingfocus?view=winrt-26100
UIElement.LosingFocus Event (Windows.UI.Xaml) - Windows apps | Microsoft Learn
Occurs before a UIElement loses focus. This event is raised synchronously to ensure focus isn't moved while the event is bubbling.
eventwindowsuixamlapps
https://learn.microsoft.com/en-us/windows/windows-app-sdk/api/winrt/microsoft.ui.xaml.input.focusmanager.losingfocus?view=windows-app-sdk-1.5
FocusManager.LosingFocus Event (Microsoft.UI.Xaml.Input) - Windows App SDK | Microsoft Learn
Occurs before focus moves from the current element with focus to the target element. This event is raised synchronously to ensure focus isn't moved while the...
windows appeventmicrosoftui