Previously, if a `Window` was `Drop`ped while open, the window would
remain open until the user pressed the x button. This fixes the
behaviour so that the window is closed when dropped if it has not
already been closed.
This can happen when window is destroyed/created during a call to user
callback as this causes WindowDelegate method to be called.
Instead if the user callback is `None` store the event in
`pending_events`.
* Remove NSTitledWindowMask for windows with no decorations. This
makes sure that they do not have a title bar.
* Transparency is not be taken into account as we could have a window
with a titlebar or without that is transparent.
invariants
This also removes the need for "box"ing the callback in favour of
storing a raw `*mut` pointer. We can do this by ensuring that we never
store the pointer for longer than the lifetime of the user callback,
which is the duration of a call to `poll_events` or `run_forever`.
Also removes old commented out event code from the window module.
This is a follow up to the new API introduced in #20.
This also fixes the issue where window resize events would not be
emitted until the end of the resize. This PR fixese #39 by ensuring that
the user callback given to either `EventsLoop::poll_events` or
`EventsLoop::run_forever` can be called by each window delegate's resize
callback directly.