使用python xlib全局捕获,忽略和发送keyevent,识别虚假输入

Question

我想在普通键盘上实现关键的和弦,我想我使用的是python xlib.为了使这个工作,程序必须全局吞下所有的关键事件,然后才允许它们通过.

我目前的测试只是抓住了"1"键.如果按下该键,它将调用一个处理程序,该处理程序通过xtest.fake_input将"x"发送到聚焦窗口.因为我只抓住"1"键,不应该有问题吧？但不知何故,处理程序再次被调用,因为"x"被按下了.事实上,当我输入"1"时,程序正在听所有键.这可能与调用有关

display.allow_events(X.ReplayKeyboard, X.CurrentTime)

处理完一个事件后,如果我不这样做,一切都会冻结.

对于最终的程序,监听行为的变化并不真正相关,但我必须能够区分假事件和用户事件.为了做到这一点,我只是快速转发display.next_event(),但这并不理想,因为用户可能会在那个确切的时刻打字而且这些击键会丢失.

我尝试在发送和清空事件队列期间释放keygrab

display.flush()
display.sync()

但那没有做任何事情.

所以,任何想法如何识别或忽略虚假输入事件以及为什么我突然听到所有按键(和发布)？

xlib非常令人沮丧.

from Xlib.display import Display
import Xlib
from Xlib import X
import Xlib.XK
import sys
import signal 

display = None
root = None

def handle_event(aEvent):
    print "handle!"
    send_key("x")

def send_key(emulated_key):

    global display,root
    print "send key"
    # ungrabbing doesnt help
    root.ungrab_key(10,X.AnyModifier) 
    window = display.get_input_focus()._data["focus"]
    # Generate the correct keycode
    keysym = Xlib.XK.string_to_keysym(emulated_key)
    keycode = display.keysym_to_keycode(keysym)
    # Send a fake keypress via xtestaaa
    Xlib.ext.xtest.fake_input(window, Xlib.X.KeyPress, keycode)
    Xlib.ext.xtest.fake_input(window, Xlib.X.KeyRelease, keycode)
    display.flush()
    display.sync()
    # fast forward those two events,this seems a bit hacky, 
    # what if theres another keyevent coming in at that exact time?
    while display.pending_events():
        display.next_event()
    #
    root.grab_key(10, X.AnyModifier, True,X.GrabModeSync, X.GrabModeSync)

def main():
    # current display
    global display,root
    display = Display()
    root = display.screen().root

    # we tell the X server we want to catch keyPress event
    root.change_attributes(event_mask = X.KeyPressMask)
    # just grab the "1"-key for now
    root.grab_key(10, X.AnyModifier, True,X.GrabModeSync, X.GrabModeSync)
    # while experimenting everything could freeze, so exit after 10 seconds
    signal.signal(signal.SIGALRM, lambda a,b:sys.exit(1))
    signal.alarm(10)
    while 1:
        event = display.next_event()
        print "event"
        #if i dont call this, the whole thing freezes
        display.allow_events(X.ReplayKeyboard, X.CurrentTime)
        handle_event(event)

if __name__ == '__main__':
    main()

Answer 1

我发现了问题。我几乎可以肯定xtest.fake_input会做一些奇怪的事情，因为当我手动发送按键和-releases时（发现了一些代码），它就可以工作

这是一个示例，该示例仅吞下按键上的“ 1”键，然后在释放按键时将“ x”发送到焦点窗口：

from Xlib.display import Display
import Xlib
from Xlib import X
import Xlib.XK
import sys
import signal 
import time
display = None
root = None

def handle_event(event):
    print "handle!"
    if (event.type == X.KeyRelease):
        send_key("x")

# from http://shallowsky.com/software/crikey/pykey-0.1 
def send_key(emulated_key):
    shift_mask = 0 # or Xlib.X.ShiftMask
    window = display.get_input_focus()._data["focus"]
    keysym = Xlib.XK.string_to_keysym(emulated_key)
    keycode = display.keysym_to_keycode(keysym)
    event = Xlib.protocol.event.KeyPress(
        time = int(time.time()),
        root = root,
        window = window,
        same_screen = 0, child = Xlib.X.NONE,
        root_x = 0, root_y = 0, event_x = 0, event_y = 0,
        state = shift_mask,
        detail = keycode
        )
    window.send_event(event, propagate = True)
    event = Xlib.protocol.event.KeyRelease(
        time = int(time.time()),
        root = display.screen().root,
        window = window,
        same_screen = 0, child = Xlib.X.NONE,
        root_x = 0, root_y = 0, event_x = 0, event_y = 0,
        state = shift_mask,
        detail = keycode
        )
    window.send_event(event, propagate = True)

def main():
    # current display
    global display,root
    display = Display()
    root = display.screen().root

    # we tell the X server we want to catch keyPress event
    root.change_attributes(event_mask = X.KeyPressMask|X.KeyReleaseMask)
    # just grab the "1"-key for now
    root.grab_key(10, 0, True,X.GrabModeSync, X.GrabModeSync)

    signal.signal(signal.SIGALRM, lambda a,b:sys.exit(1))
    signal.alarm(10)
    while 1:
        event = display.next_event()
        print "event"
        handle_event(event)
        display.allow_events(X.AsyncKeyboard, X.CurrentTime)            

if __name__ == '__main__':
    main()