如何解决是否可以将函数传递给类并进行存储，以便可以响应事件来调用它？
我试图将键盘控件添加到我用来控制机器人的Tkinter程序中。我的目标是让某些按键在按下时运行一个运动命令，在释放它们时运行一个停止命令。
在this Stack Overflow post的帮助下，我设法完成了这项工作，但是该方法要求我将函数调用写入用于删除键的自定义KeyTracker类中，这很不方便。创建新实例时，是否可以通过某种方法将希望键调用的函数作为参数传递给KeyTracker类？例如，对于W键，这可能是以下两者之一：
# To bind events to the press and release of the W key:
self.key_tracker_W = KeyTracker('W','w',self.key_pressed_W,self.key_released_W)
top.bind( "<KeyPress-w>",self.key_tracker_W.report_key_press )
top.bind( "<keyrelease-w>",self.key_tracker_W.report_key_release )
或
# To bind events to the press and release of the w key:
self.key_tracker_W = KeyTracker('W','w')
top.bind( "<KeyPress-w>",self.key_tracker_W.report_key_press(self.key_pressed_W) )
top.bind( "<keyrelease-w>",self.key_tracker_W.report_key_release(self.key_released_W) )
这样，我可以根据需要多次使用该类，而不必为每次使用添加代码。
我制作了按比例缩小的示例程序。打开窗口后，如果按W，A，S或D键，则会在外壳上打印相应的文本。
##############################################################################################
## IMPORT LIBRARIES:
import tkinter as tk
import time
import threading
##############################################################################################
## Debouncer For Keyboard Events:
class KeyTracker():
#=====================================================================================
"""
The code for this class was modified from an example found at:
https://stackoverflow.com/questions/27215326/tkinter-keypress-keyrelease-events
The KeyPress event gets called twice,but that isn't a problem for my needs.
"""
#=====================================================================================
def __init__(self,KEY_U,KEY_L):
self.key_U = KEY_U
self.key_L = KEY_L
self.last_press_time = 0
self.last_release_time = 0
#=====================================================================================
def is_pressed(self):
return time.time() - self.last_press_time < 0.1
#=====================================================================================
def report_key_press(self,event):
if (event.keysym == self.key_U or event.keysym == self.key_L):
if not( self.is_pressed() ):
print("Key pressed")
# I don't like having to have this if statement here:
if (self.key_U == 'W'): app.key_pressed_W()
elif (self.key_U == 'A'): app.key_pressed_A()
elif (self.key_U == 'S'): app.key_pressed_S()
elif (self.key_U == 'D'): app.key_pressed_D()
# I would rather be calling a function that was passed to the class as an argument.
self.last_press_time = time.time()
#=====================================================================================
def report_key_release(self,event):
if (event.keysym == self.key_U or event.keysym == self.key_L):
self.timer = threading.Timer(0.1,self.report_key_release_callback,args = [event])
self.timer.start()
#=====================================================================================
def report_key_release_callback(self,event):
if not(self.is_pressed()):
print("Key Released")
# I don't like having to have this if statement here:
if (self.key_U == 'W'): app.key_released_W()
elif (self.key_U == 'A'): app.key_released_A()
elif (self.key_U == 'S'): app.key_released_S()
elif (self.key_U == 'D'): app.key_released_D()
# I would rather be calling a function that was passed to the class as an argument.
self.last_release_time = time.time()
#=====================================================================================
##############################################################################################
## Class For Creating The Main Window:
class CLASS_Window_Main(tk.Frame):
#=====================================================================================
def __init__(self,master = None):
#-------------------------------------------------------------------------
tk.Frame.__init__(self,master) # super().__init__(master)
#-------------------------------------------------------------------------
self.grid( sticky = tk.N + tk.S + tk.E + tk.W ) # Resize window contents when window is resized.
self.GUI_Create_Widgets()
#-------------------------------------------------------------------------
#=====================================================================================
def GUI_Create_Widgets(self):
#-------------------------------------------------------------------------
## Create Window:
top = self.winfo_toplevel()
top.rowconfigure( 0,weight = 1 )
top.columnconfigure( 0,weight = 1 )
#-------------------------------------------------------------------------
## Bind Window Resized Event:
top.bind( "<Configure>",self.GUI_Window_Resized )
#-------------------------------------------------------------------------
## Bind Keyboard Events:
# Bind events to the W key:
self.key_tracker_W = KeyTracker('W','w')
top.bind( "<KeyPress-w>",self.key_tracker_W.report_key_press )
top.bind( "<KeyPress-W>",self.key_tracker_W.report_key_press )
top.bind( "<keyrelease-w>",self.key_tracker_W.report_key_release )
top.bind( "<keyrelease-W>",self.key_tracker_W.report_key_release )
# Bind events to the A key:
self.key_tracker_A = KeyTracker('A','a')
top.bind( "<KeyPress-a>",self.key_tracker_A.report_key_press )
top.bind( "<KeyPress-A>",self.key_tracker_A.report_key_press )
top.bind( "<keyrelease-a>",self.key_tracker_A.report_key_release )
top.bind( "<keyrelease-A>",self.key_tracker_A.report_key_release )
# Bind events to the S key:
self.key_tracker_S = KeyTracker('S','s')
top.bind( "<KeyPress-s>",self.key_tracker_S.report_key_press )
top.bind( "<KeyPress-S>",self.key_tracker_S.report_key_press )
top.bind( "<keyrelease-s>",self.key_tracker_S.report_key_release )
top.bind( "<keyrelease-S>",self.key_tracker_S.report_key_release )
# Bind events to the D key:
self.key_tracker_D = KeyTracker('D','d')
top.bind( "<KeyPress-d>",self.key_tracker_D.report_key_press )
top.bind( "<KeyPress-D>",self.key_tracker_D.report_key_press )
top.bind( "<keyrelease-d>",self.key_tracker_D.report_key_release )
top.bind( "<keyrelease-D>",self.key_tracker_D.report_key_release )
#-------------------------------------------------------------------------
#=====================================================================================
## Run This Function When The Window Is Resized:
def GUI_Window_Resized(self,event):
print("The window was resized")
#=====================================================================================
## Functions To Be Run In Response To Keys:
def key_pressed_W(self):
print("KEYPRESS = W")
def key_released_W(self):
print("keyrelease = W")
def key_pressed_A(self):
print("KEYPRESS = A")
def key_released_A(self):
print("keyrelease = A")
def key_pressed_S(self):
print("KEYPRESS = S")
def key_released_S(self):
print("keyrelease = S")
def key_pressed_D(self):
print("KEYPRESS = D")
def key_released_D(self):
print("keyrelease = D")
#=====================================================================================
##############################################################################################
## RUN PROGRAMME:
print("Programme Start")
# Run the Tkinter programme:
root = tk.Tk()
root.geometry("200x200") # Set the default size of the window.
app = CLASS_Window_Main() # Create CLASS_Window_Main instance.
app.master.title("Window Title") # Set the title of the window.
app.mainloop() # Start CLASS_Window_Main.
##############################################################################################
我知道我可以按原样使用我现在拥有的东西，但是我内心的完美主义者一直在me我，说他希望班级变得“更通用”。您能提供的任何帮助将不胜感激。
解决方法
是否可以将函数传递给类并进行存储，以便可以对事件进行调用？
是的，您可以像这样传递函数。
在您的示例中，您只需将回调保存在__init__方法中，然后在以后使用。
class KeyTracker():
def __init__(self,KEY_U,KEY_L,press_callback,release_callback):
self.press_callback = press_callback
self.release_callback = release_callback
...
您稍后可以像使用任何功能一样使用它：
class KeyTracker():
def report_key_release_callback(self,event):
# call the stored callback
self.release_callback(event)
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