如何在tkinter中将多个按钮链接到一个文本小部件？

Question

I'm trying to learn tkinter and I wanted to write a simple rock paper scissors game, where there is a window with 3 buttons and one text widget.

I'd like to be able to press any of the buttons and for the message to appear in the text field, then click a different button, the text field to clear and display a new message associated with the second button and so on.

From the tutorials I've watched, I know that I can pass the function housing text widget as an argument in button command parameter.I know I could make 3 functions with a text field, one for each button (displaying one at a time) but that's probably not the correct way. Here's what I have so far:

import tkinter as tk

root = tk.Tk()
root.title("Rock Paper Scissors")
root.geometry("420x200")

def Rock():
    rockText = "Paper!"
    return rockText

def Paper():
    paperText = "Scissors!"
    return paperText

def Scissors():
    scissorsText = "Rock!"
    return scissorsText

def display():

    textDisplay = tk.Text(master = root, height = 10, width = 50)
    textDisplay.grid(row = 1, columnspan = 5)
    textDisplay.insert(tk.END, Rock())

buttonRock = tk.Button(text = "Rock", command = display).grid(row = 0, column = 1, padx = 10)
buttonPaper = tk.Button(text = "Paper").grid(row = 0, column = 2, padx = 10)
buttonScissors = tk.Button(text = "Scissors").grid(row = 0, column = 3, padx = 10)

root.mainloop()

Any help will be appreciated.

Edit: Second thought - I can imagine I'm complicating this for myself by trying to force the game to work this way. With the random module I'd be able to get away with one function for the computer choice with a list and saving the random pick in a parameter, then returning the value into the display function.

Answer 1

So if I got this right you just want to make a button click change the text in the Text-widget. For that you have two easy and quite similar options. First would be to define 3 functions, as you did, and let them change the text directly. The second option would be to make one function which changes the text according to whats given. Note that in the second case we will have to use lambda which works quite well in smaller projects but decreases the efficiency of your programs when they get bigger.

First option:

import tkinter as tk

class App:
    def __init__(self):
        root=tk.Tk()
        root.title("Rock Paper Scissors")
        root.geometry("420x200")
        self.text=Text(root)
        self.text.grid(row=1,columnspan=5)
        tk.Button(root,text="Rock",command=self.Rock).grid(row=0,column=1,padx=10)
        tk.Button(root,text="Paper",command=self.Paper).grid(row=0,column=2)
        tk.Button(root,text="Scissors",command=self.Scissors).grid(row=0,column=3,padx=10)
        root.mainloop()

    def Rock(self):
        text="Paper!"
        self.text.delete(0,END) #delete everything from the Text
        self.text.insert(0,text) #put the text in

    def Paper(self):
        text="Scissors!"
        self.text.delete(0,END) #delete everything from the Text
        self.text.insert(0,text) #put the text in

    def Scissors(self):
        text="Rock!"
        self.text.delete(0,END) #delete everything from the Text
        self.text.insert(0,text) #put the text in

if __name__=='__main__':
    App()

Second option:

import tkinter as tk

class App:
    def __init__(self):
        root=tk.Tk()
        root.title("Rock Paper Scissors")
        root.geometry("420x200")
        self.text=Text(root)
        self.text.grid(row=1,columnspan=5)
        tk.Button(root,text="Rock",command=lambda: self.updateText('Paper!')).grid(row=0,column=1,padx=10)
        tk.Button(root,text="Paper",command=lambda: self.updateText('Scissors!')).grid(row=0,column=2)
        tk.Button(root,text="Scissors",command=lambda: self.updateText('Rock!')).grid(row=0,column=3,padx=10)
        root.mainloop()

    def updateText(self,text):
        self.text.delete(0,END) #delete everything from the Text
        self.text.insert(0,text) #put the text in

if __name__=='__main__':
    App()

Some little side notes from me here:

1. If you use grid , pack or place right on the widget itself you wont assign the widget to a variable but the return of the grid , pack or place function which is None . So rather first assign the widget to an variable and then use a geometry manager on it like I did for the Text -widget.
2. You don't have to extra set the title with the title function afterwards. You can set it with the className -argument in Tk .
3. If you're working with tkinter its fine to do it functionally but rather use a class to build up GUIs.
4. When creating new widgets always be sure to pass them the variable for the root window first. They will get it themselves too if you don't do that but that needs more unnecessary background activity and if you have more than one Tk -window open it will automatically chooses one which may not be the one you want it to take.
5. And one small tip in the end: If you want to learn more about all the tkinter widgets try http://effbot.org/tkinterbook/tkinter-index.htm#class-reference .

I hope its helpfull. Have fun programming!

EDIT: I just saw your edit with the random module. In this case I would recommend the second option. Just remove the text -argument from updateText and replace lambda: self.updateText(...) with self.updateText() . In updateText itself you add that random of list thing you mentioned. :D