https://learn.microsoft.com/en-us/windows/windows-app-sdk/api/winrt/microsoft.ui.xaml.controls.primitives.flyoutbase.showattachedflyout?view=windows-app-sdk-2.0
FlyoutBase.ShowAttachedFlyout(FrameworkElement) Method (Microsoft.UI.Xaml.Controls.Primitives) -...
Shows the flyout associated with the specified element, if any.
methodmicrosoftuixamlcontrols