GObject信号和GLib MainLoop

Question

我有一个在某个线程中发出信号的GObject-derived对象，我想在运行GLib的MainLoop的主线程中处理它们。

import gi
from gi.repository import GObject, GLib

class SomeObj(GObject.Object, threading.Thread):
    def __init__(self, device_path, terminate_event):
        GObject.Object.__init__(self)
        threading.Thread.__init__(self)

    def run():
        ...
        self.emit('sig')
        ...

    @GObject.Signal
    def sig(self):
        pass

def callback(instance):
    ...
    # will be called in obj's thread

loop = GLib.MainLoop()
obj = SomeObj()
self.watcher.connect('sig', callback)
obj.start()
loop.run()

callback()将在obj的线程中调用。如何在loop.run()中处理主线程中的信号

Answer 1

将事件从callback信号处理程序推送到主线程的主上下文：

def callback(instance):
    # None here means the global default GMainContext, which is running in your main thread
    GLib.MainContext.invoke(None, callback_main, instance)

def callback_main(instance):
    # Double check that we’re running in the main thread:
    assert(GLib.MainContext.is_owner(None))
    # … the code you want to be executed in the main thread …