Arguments: &key window exit-test
Enters a loop that processes all messages that are sent to any windows that are created in the thread that is calling event-loop. When an application creates a new thread that will create windows, the preset-function that is passed to process-run-function should call event-loop before it exits, both to cause that thread's messages to be handled and also to prevent the thread from exiting until it should. The arguments determine when event-loop will return, which then allows the thread to exit.
window may be nil or a
window. If a window, then event-loop will check that the
window is still open after processing each message, and return when
the window has been closed. Typically a "main window" for the thread
is passed to event-loop.
exit-test may be nil or
a function name or function object. If non-nil, then event-loop will call the exit-test
function once after it has processed each message, and return if the
function returns true. For efficient
event-handling, an exit-test if used should execute quickly. The
function should take one argument, which is the value of the
window argument to event-loop. An exit-test may be
used along with a null window argument (in which case the argument to
the exit-test function will be nil), but it is probably most often
useful to pass a main-window as well when an exit-test is used.
Note: It is not necessary to call event-loop when using the project system to create an application with a single windowing thread, because it is called automatically for the thread created by the Run | Run Project command in the IDE and by the corresponding initial thread of the generated standalone application. It is also not necessary to call event-loop when creating windows by evaluating forms in IDE listeners or editors, since the threads used for evaluation by these IDE windows are already in event-handling loops.
event-loop basically calls process-single-event in a loop until an exit requirement is met. So if event-loop does not meet an application's needs, it may work to use a custom loop that calls process-single-event itself. But event-loop performs some additional internal management and is recommended over custom process-single-event loops. In particular, event-loop ensures that multiple threads that call it will all exit cleanly when lisp exits; otherwise multiple windowing threads may hang on exit unless the :no-unwind argument is passed to exit.
See also About using multiple windowing threads in a CG application in cgide.htm.
Common Graphics and IDE documentation is described in About Common Graphics and IDE documentation in cgide.htm.
The documentation is described in introduction.htm and the index is in index.htm.
Copyright (c) 1998-2000, Franz Inc. Berkeley, CA., USA. All rights reserved.
Created 2000.10.5.