In the last time we've received enough user reactions to regard this as a
serious problem. Allow me to explain the problem from a broader perspective.

Palm OS philosophy:
An app registers as a handler of particular file (or mime) type. E.g. a
viewer registers as a .jpg handler, an audio player as .mp3 handler.
Additionally, the app can declare itself as the default handler and become
this way kind of privileged among all handlers serving particular file type.

When a file is received (beam, BT...) the OS accepts the data and calls the
default handler to process it. (For some strange reason the OS is not able
to refuse the data in the first phase of the transfer if there is no handler
for the data type - but that's another question.)

If the user installed alternative handlers for the same type he faces a
problem: how to tell which handler should receive the data.

Palm suggests that apps should offer the list of available handlers and let
the user to chose. Some apps really do it (e.g. some email programs), some
never did so and some (like our viewer) gave up doing so after this way
proved risky due to Palm OS bug. (Discussed on this forum a few months ago.)

Some of the viewers started in the last time a policy that I would describe
as aggressive. They try to force their registration at every possible
instance:
- During the reset notification.
- Also during some BT notifications (don't know exactly which ones, but it
shouldn't be a problem to find it out)
Examples: Palm Photos, SplashPhoto, Web Pro.
A nice effect happens, when an expired viewer forces its registration.
An even nicer effect: Two viewers start a war registering itself in reaction
to a suitable notifications producing thus a circular deadlock. Actually I
am not sure that this happens, but 1. it could happen, 2. I experienced some
deadlocks that could be well explained this way.

We are now before the decision how to react:
- Ignore the war and become the losers
- Join the war and make the Palm behavior still less predictable or even
dangerous. We can add some tricks and win temporarily, but at the end when
every viewer will behave this way, the result will be basically random.

The final loser will be the user and his dissatisfaction has known
consequences.

I do not know a good solution and would like to listen to the opinions of
the other programmers.

Jan Slodicka


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