On Aug 31, 2009, at 11:53 PM, Mike Wilson wrote:
This requirement could be solved in several other ways, f ex making
sure that the "standard" timeout period is short enough to not be
longer than what any app wants. Then (as was previously suggested)
an app that wants a longer timeout can do setTimeout and trigger its
own idle stuff if status has not come back to "active" during that
time.
This seems reasonable. Different apps really do want different idle-
time thresholds (if only for compatibility with other manifestations
of the app, i.e. an IM platform), but I think the event-plus-custom-
timeout mechanism would let them achieve that.
Another alternative is to have no event, and just a property:
window.lastUserActionTime
which is kept updated with the "msec since epoch" for the latest
user input on the desktop. Then an app can implement its own idle
functionality with totally own rules. This API has the drawback of
maybe exposing too much information (the rate of input events to
other apps), but may spawn some ideas.
This would have to be deliberately fuzzed, as it is apparently
possible to guess user typing by looking at the timing between
keystrokes. Rounding it to the nearest second would probably suffice.
The problem with this API is that, once the app determines the user is
idle, it has to keep polling lastUserActionTime until it sees it
change. I'm not fond of APIs that require the client to poll.
The best solution, I think, would be both of the above. The
lastUserActionTime property lets a page test whether the user's
already idle at the time it loads, and the event lets it detect
transitions without having to poll.
—Jens
