[Slowmoe]

Hi,

I've got a little problem with threads in Python. Up to now, I only know Threads from Java, but it should be similar in Python.


The following code refreshes an image on the display if the accelerometer gets a specific orientation event! That works fine.

Additionally it should now play a specific mp3 for a specific orientation event (parallel/synchronized to refreshing the image). I tried to realize this by the code marked in red!

...
args = "", ""
soundFB = thread

def paintScreen(range, source):
    canvas.blit(source)

def playSound(empty1, empty2):
    input = UpSound
    input.set_volume(2)
    input.play(times=1, interval=0, callback=None)
    input.stop()

def print_orientation(orientation_value):
    #print >> to_peer, orientations[orientation_value]
    if orientations[orientation_value] == 'Up':
        paintScreen((), UpImage)
        soundFB.start_new_thread(playSound, args)
...

Assumed that print_orientation() is allready called:

The "playSound" method seems to start, the image becomes refreshed, but no sound is played and then the whole application freezes.

(the playSound method on it's own works fine! It's just the combination with the thread!)

Can anybody give me an advise how to handle this problem?

[miohtama]

Originally Posted by Slowmoe

Hi,

I've got a little problem with threads in Python. Up to now, I only know Threads from Java, but it should be similar in Python.

Since you didn't post full source code a precise answer is impossible to give.

Threads on Python mostly work fine - like threads on Java. But threads on Symbian are f*cked up. Namely, you cannot share native objects across the threads (files, sockets). This is due to limitations in Symbian "server" architecture. Usual symptoms are untraceable lock ups or application crashes. Also, some functions are callable on the main thread only.

Internally PyS60 maps threads to Symbian Active Objects - read more about architectural limitations here - article about Microsoft trying port .NET framework on Symbian: http://www.jot.fm/issues/issue_2006_04/article4/

1. Try create all objects in the same thread they are accessed.

2. See multithread debugging/exception tracing tips from this example app:

http://bazaar.launchpad.net/~pys60co...7in81mt9gmhv-6

[Slowmoe]

Hi,

up to now my application runs stable (including the audio thread), but one thing is mysterious.

The "playSound" method runs in a thread without exceptions, the audio states are correct and the sound is played, but I can't hear the sound!


I've checked my mobile phone profile ("general") two times.

Is it generally impossible to run the audio module in a thread?!?!

With a normal call (without thread) the same method runs well and I can hear the sound.