Series 60 5th Edition high-level UI bug

[grahamhughes]

OK... I am seeing spurious abrupt terminations of my app (no exception, no message at all), which occur only on S60 5th edition devices. I have finally tracked it down to the MIDP high-level UI implementation.

It appears to relate to the construction and tear-down of Forms and their contained Items.

I've attached a sample app that reproduces the problem.

I can reproduce this issue on:

* 5800XpressMusic, 20.0.012.C02.01
* N97 mini, 12.0.110.C01.01

It would be of great help to know what (internally) is causing this problem, and if there is any work-around more specific than "don't create and destroy Forms or Items".

Graham.

[grahamhughes]

Curiously, can't reproduce the issue on a Sony Ericsson U1 (1224-3789_R1BA027).

I seem to be able (at least in the test app), to remove the problem by:

Replacing:

forms[i].destroy();

with:

forms[i].destroy();
System.gc();
try {
    Thread.sleep(200);
} catch (InterruptedException e) {
    // ignore
}

Or, by never creating any ChoiceGroups of type MULTIPLE.

Whether these "fix" the problem, or just nudge it further away, I obviously have no idea.

Graham.

[grahamhughes]

Any help...?

[grahamhughes]

I thought I'd fixed this, by not destroying MULTIPLE ChoiceGroup objects... but on the 5230, I'm now seeing "IllegalStateException: addNotify when already added" (see also this issue), which appears to originate inside the API implementation. I believe these issues are related.

There is also some suggestion from the testers that the original issue has not entirely gone away, they've seen it again (in spite of my fix) on an N97.

Graham.

[grahamhughes]

A-ha!!

The IllegalStateException is my fault... because I was keeping a reference to the ChoiceGroup, then adding it to another Form, it was (quite correctly) complaining. Perhaps a bug in the 5800XM that it doesn't throw an exception in this case...

In my new test, I'm calling deleteAll() on the Form before dropping my reference to it, and I'm going back to allowing all the Items to become garbage too (including the MULTIPLE typed ChoiceGroup). First test on the N97 seems to suggest that this works - fixing the crash-out issue. Needs more testing.

Graham.

[ehudshapira]

So it's good now?

[grahamhughes]

Yes, calling deleteAll() on a Form before allowing the Form to become garbage seems to prevent the abrupt termination.

Graham.