Pushes this event handler onto the event handler stack for the window.
An event handler is an object that is capable of processing the events
- sent to a window. (In other words, is able to dispatch the events to
+ sent to a window. (In other words, is able to dispatch the events to a
handler function.) By default, the window is its own event handler,
but an application may wish to substitute another, for example to
allow central implementation of event-handling for a variety of