pub trait EventHandler {
// Required methods
fn key_focus_in(&mut self, layer: &mut Layer);
fn key_focus_out(&mut self, layer: &mut Layer);
fn key_down(&mut self, key: Key, layer: &mut Layer);
}pub trait EventHandler {
// Required methods
fn key_focus_in(&mut self, layer: &mut Layer);
fn key_focus_out(&mut self, layer: &mut Layer);
fn key_down(&mut self, key: Key, layer: &mut Layer);
}