Path: utzoo!attcan!uunet!snorkelwacker!bloom-beacon!LARRY.MCRCIM.MCGILL.EDU!mouse
From: mouse@LARRY.MCRCIM.MCGILL.EDU
Newsgroups: comp.windows.x
Subject: Re:  Detecting a double-click
Message-ID: <9009301901.AA20799@Larry.McRCIM.McGill.EDU>
Date: 30 Sep 90 19:01:48 GMT
Sender: root@athena.mit.edu (Wizard A. Root)
Organization: The Internet
Lines: 33

> Is there a general way to detect a double-click in a window ?

No.

> I want to be able to distinguish between 3 things the user can do.

> a) Button press, drag and release.
> b) Single click.
> c) Double click.

> Let's say I need to take actions A, B and C in the 3 cases,
> respectively.  Now, if I receive a click, I don't know whether it is
> a single-click (and should perform action B) or the first click of a
> double-click (and should perorm action C).

That's right, you don't.  X does not provide the tools to do proper
double-click recognition; I am hoping that R5 will improve this.  At
present you have to either (i) make sure that action B can be undone or
subsumed into action C or (ii) do the timing for double-click detection
in the client and hope network delays don't bite you.

There are many possible solutions, of varying degrees of generality and
usefulness; the one I currently prefer is some way to ask the server to
send a timeout event following each other event after some delay.  Some
of the variable factors would be what types of events timeouts can be
requested for, how the timeout is specified (globally, per event type,
per client, etc), what (if any) other events occurring in the interim
will suppress the timeout event, etc.

					der Mouse

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			new: mouse@larry.mcrcim.mcgill.edu