Python绑定–允许同时按下多个键

我在Python中遇到了问题.

我正在使用Tkinter并且有四个绑定事件,它们会在我的表单上按下按键.
我的问题是,这些不是异步运行的.因此,例如,我可以按一个按钮,并识别事件.但是,当我同时按住两个键时,只有一个事件被触发.

有没有其他方法可以做到这一点？

self.f.bind("w", self.player1Up)
self.f.bind("s", self.player1Down)
self.f.bind("o", self.player2Up)
self.f.bind("l", self.player2Down)


解决方法:

不幸的是,您在某种程度上受到系统底层自动重复机制的支配.例如,在我正在使用的Mac上,如果我按住“w”,我将获得一系列新闻和发布事件.按下时,如果我按下“o”,我会得到“o”的按下和释放流,但没有“w”的事件.

您需要设置一个迷你状态机,并绑定到按键和键释放事件.这将让您跟踪哪些键被按下以及哪些键没有按下.然后,每次绘制框架时,您都可以查询机器以查看按下哪些键并相应地执行操作.

这是一个快速的黑客,我扔在一起.我只在我的Mac上测试过它,只用python 2.5.我没有真正尝试过“pythonic”或高效率.该代码仅用于说明该技术.使用此代码,您可以同时按“w”或“s”和“o”或“l”来上下移动两个拨片.

'''Example that demonstrates keeping track of multiple key events'''
from Tkinter import *
class Playfield:
def __init__(self):
# this dict keeps track of keys that have been pressed but not
# released
self.pressed = {}
self._create_ui()
def start(self):
self._animate()
self.root.mainloop()
def _create_ui(self):
self.root = Tk()
self.p1label = Label(text="press w, s to move player 1 up, down",
anchor="w")
self.p2label = Label(text="press o, l to move player 2 up, down",
anchor="w")
self.canvas = Canvas(top", fill="x")
self.p2label.pack(side="top", fill="x")
self.canvas.pack(side="top", fill="both", expand="true")
self.p1 = Paddle(self.canvas, tag="p1", color="red", x=0, y=0)
self.p2 = Paddle(self.canvas, tag="p2", color="blue", x=400, y=0)
self._set_bindings()
def _animate(self):
if self.pressed["w"]: self.p1.move_up()
if self.pressed["s"]: self.p1.move_down()
if self.pressed["o"]: self.p2.move_up()
if self.pressed["l"]: self.p2.move_down()
self.p1.redraw()
self.p2.redraw()
self.root.after(10, self._animate)
def _set_bindings(self):
for char in ["w","s","o", "l"]:
self.root.bind("" % char, self._pressed)
self.root.bind("" % char, self._released)
self.pressed[char] = False
def _pressed(self, event):
self.pressed[event.char] = True
def _released(self, event):
self.pressed[event.char] = False
class Paddle():
def __init__(self, canvas, tag, color="red", x=0, y=0):
self.canvas = canvas
self.tag = tag
self.x = x
self.y = y
self.color = color
self.redraw()
def move_up(self):
self.y = max(self.y -2, 0)
def move_down(self):
self.y = min(self.y + 2, 400)
def redraw(self):
x0 = self.x - 10
x1 = self.x + 10
y0 = self.y - 20
y1 = self.y + 20
self.canvas.delete(self.tag)
self.canvas.create_rectangle(x0,y0,x1,y1,tags=self.tag, fill=self.color)
if __name__ == "__main__":
p = Playfield()
p.start()