pub trait ChildProxyExt: 'static {
fn child_added<P: IsA<Object>>(&self, child: &P, name: &str);
fn child_removed<P: IsA<Object>>(&self, child: &P, name: &str);
fn child_by_index(&self, index: u32) -> Option<Object>;
fn child_by_name(&self, name: &str) -> Option<Object>;
fn children_count(&self) -> u32;
fn connect_child_added<F: Fn(&Self, &Object, &str) + Send + Sync + 'static>(
&self,
f: F
) -> SignalHandlerId;
fn connect_child_removed<F: Fn(&Self, &Object, &str) + Send + Sync + 'static>(
&self,
f: F
) -> SignalHandlerId;
}