Function on_visibility_changed 

pub fn on_visibility_changed(
    child: impl IntoUiNode,
    handler: Box<dyn FnMut(&Visibility) -> HandlerResult + Send>,
) -> UiNode

P Widget visibility changed.

Note that there are multiple specific events for visibility changes, on_visible, on_hidden and on_collapsed.

Route

This event property uses a direct route, that is, it cannot be intercepted in parent widgets.