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I found the answer. Gstreamer callbacks are being made on the pipeline thread context. All I needed to do is put a Glib::Dispatcher to signal the app thread context. So now the code works in this order: gstreamer_callback->static PlayFile method->Glib::Dispatcher(changes to the app thread context)->another PlayFile method->signal main_window->method on main_window that displays Gtk::MessageDialog->it works Caution to other readers: Be careful of shared data access. In my case scenario(gstreamer+gtkmm) use a Glib::Dispatcher to signal code which operates on gui functions. non-gui functions operate well in the pipeline context(especially when you call gstreamer functions). From: sledgehammer_999 hotmail com To: gtkmm-list gnome org Subject: Is this a threading issue? Date: Wed, 9 Sep 2009 20:46:48 +0300 Hi I am developing a media player app using gtkmm and gstreamer. Unfortunately it isn't yet in a state for sources to be released. I am encountering a problem and I can't seem to solve it. Furthermore this problem is somewhat random. The code occasionally works as it should, but most of the time it crashes. This code is called after a series of signals/callbacks. I'll attempt to explain: main_window class is a classed derived from Gtk::Window Playfile class is my own custom class, it isn't based on any widget, it just uses libsigc for signals In Playfile I connect a gstreamer callback to a method of Playfile which is static. When this method is called, it is passed a pointer to the instance of Playfile. I use this pointer to call another method of Playfile(needed to access the instance's vars). This method, does some work and finally it emits a signal. This signal is catched by a method in the main_window instance. Then in that method I create a Gtk::MessageDialog. But when I try to run() it the app crashes(most of the time). The only error I get in the console is this: media_player: ../../src/xcb_io.c:176: process_responses: Assertion `!(req && current_request && !(((long) (req->sequence) - (long) (current_request)) <= 0))' failed. media_player is the name of the app. I know that I haven't given you any code, but do you have any idea what is happening? Since it sometimes works, I suspect that this is a threading issue(in gtkmm/gtk or gstreamer). I don't use threads, the app is single threaded. Do you have any suggestions on what to do? Μοιραστείτε τις αναμνήσεις σας μέσω Internet με τους φίλους σας με τους φίλους σας. Μείνετε συνδεδεμένοι με τους φίλους σας στο Zoo Κάντε κλικ εδώ! |