+ Glib::RefPtr<Glib::MainContext> m_context;
+ Glib::Threads::Thread* run_loop_thread;
+ Glib::Threads::Mutex _run_lock;
+ Glib::Threads::Cond _running;
+
+ /* this signals _running from within the event loop,
+ from an idle callback
+ */
+
+ bool signal_running ();
+
+ /** Derived UI objects can implement thread_init()
+ * which will be called by the event loop thread
+ * immediately before it enters the event loop.
+ */