Python 2.7：Tkinter，如何使用綁定方法？

Question

我想用Python創建一個Scrabble遊戲。我想在用戶輸入單詞時顯示該單詞的價值。 我已經問過這個問題，因爲我不知道使用什麼方法。當我發現使用哪種方法時，我的問題是如何使用這種方法，我認爲這有一個新問題。 我的問題是我創建了一個名爲bind_entry(event)的函數，應該在用戶每次輸入一個字母時設置一個標籤。但函數bind_entry(event)不知道要設置的標籤和單詞所在的條目。

這裏是我的代碼：

#this the function creating the label 
def create_variabletext_intlabel(root,col,row): 
    val=IntVar() 
    label=Label(root,textvariable=val) 
    label.grid(column=col,row=row) 
    return val, label 

#this is the function creating the entry 
def create_entry_string(root,width,col,row,columnspan,rowspan): 
    val=StringVar() 
    entry=ttk.Entry(root,width=width,textvariable=val) 
    entry.grid(column=col,row=row,columnspan=columnspan,rowspan=rowspan) 
    entry.bind("<Any-KeyPress>",bind_entry) 
    #Here is my problem, when I call the function bind_entry. 
    return val, entry 

def bind_entry(event): 
    label.set(m.counting_point(char(event))) 
    # m.counting_point() is a function counting the word's points 
    # my problem is that the function doesn't know yet the label. 
    # I don't know how to call the label. 

# I call the function create_entry_string in another file initiating 
# all the widget for the GUI 
val_entry_word, entry_word =g.create_entry_string(root,15,1,1,1,1) 

# I call the function create_variabletext_intlabel in another file 
# initiating all the widget for the GUI 
val_points,label_points=g.create_variabletext_intlabel(root,1,2) 

我只注意到功能m.counting_points()只會計算由用戶鍵入的字母。在這裏我應該打電話給val_entry_word。

因此，這裏是我的問題：

由於val_entry_word和val_points在函數創建在另一個文件中我怎麼能調用的函數bind_entry()val_entry_word和val_points？

Answer 1

通常，當您需要不同的函數調用來共享信息而不明確傳遞信息時，最佳做法是使用一個類。

例如

class LabelUpdater(object): 
    def create_variabletext_intlabel(self,root,col,row): 
     val=IntVar() 
     self.label=label=Label(root,textvariable=val) 
     label.grid(column=col,row=row) 
     return val, label 

    #this is the function creating the entry 
    def create_entry_string(self,root,width,col,row,columnspan,rowspan): 
     val=StringVar() 
     entry=ttk.Entry(root,width=width,textvariable=val) 
     entry.grid(column=col,row=row,columnspan=columnspan,rowspan=rowspan) 
     entry.bind("<Any-KeyPress>",self.bind_entry) 
     #Here is my problem, when I call the function bind_entry. 
     return val, entry 

    def bind_entry(self,event): 
     self.label.set(m.counting_point(char(event))) 

#At this point, I don't understand your code anymore since I don't know what g 
#is or how it's create_entry_string method calls your create_entry_string function... 
#I'll assume that the module where g's class is defined imports this file... 
#If that's how it works, then the following may be ok, although probably not because 
#of circular imports... 

container=LabelUpdater() 
create_variabletext_intlabel=container.create_variabletext_intlabel 
create_entry_string=container.create_entry_string 

val_entry_word, entry_word =g.create_entry_string(root,15,1,1,1,1) #somehow calls create_variabletext_intlabel which is mapped to container.create_variable_intlabel??? 

# I call the function create_variabletext_intlabel in another file 
# initiating all the widget for the GUI 
val_points,label_points=g.create_variabletext_intlabel(root,1,2) 

當然，你也可以使用全局變量...（雖然這肯定是不鼓勵）

最後，我經常要用到的綁定回調添加附加信息的成語是包裝回調函數在另一個函數中...

def myfunc(root): 
    label=Label(root,text="cow") 
    label.pack() 
    return label 

#This is the callback we want... 
# Q: but how do we pass S? 
# A: we need to wrap this call in another -- a perfect use for lambda functions! 
def change_label(label,S): 
    label.config(text=S) 

root=Tk() 
lbl=myfunc(root) 
lbl.bind("<Enter>",lambda e: change_label("Horse")) 
lbl.bind("<Leave>",lambda e: change_label("Cow"))