This would solve the most important use case for #116. Only the Linux
version has been tested, but the Windows should work perfectly fine, and
I don't know anything about macOS programming but that version also
compiles so it should be fine.
Since this isn't emitted anywhere, this can only lead to confusion for
library consumers. They'd need to implement their own click detection
with the button up and button down events.
* Add mutable event status argument to WindowHandler::on_event
* macOS: simplify method declaration for simple mouse event handlers
* macOS: add macro for adding simple keyboard class methods
* macOS: reorder code in mouse_moved
* Take EventStatus as return value in WindowHandler::on_event
* Add doc comments for EventStatus
* Improve EventStatus documentation
* x11: ignore return value of on_event for now
* EventStatus: improve docs
* Improve EventsStatus docs
* Improve EventStatus docs further
* macOS: ignore EventStatus::Ignored for mouse events
* macOS: minor formatting improvement
* improve EventStatus docs again