文本未在 Tkinter 中显示

Question

我有以下代码，错误是缺少 1 个位置参数（文本）。据我所知，我已经包含了所有论点。任何人都可以对此有所了解吗？

错误

TypeError: draw_text() missing 1 required positional argument: 'text'

有问题的代码

while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            tk.update()
            ball1.draw()
            bat1.draw()
        else:
            draw1=Game()
            draw1.draw_text(300,200,'Goodbye')

        time.sleep(0.02) 
main()

在其中定义 draw_text 的类。

class Game:
    def game_loop(self,canvas):
        if hit_bottom==True:
            self.draw_text(300,200,'You Lose')
    def draw_text(self,canvas,x,y,text,size='40'):
        font=('Helvetica',size)
        return self.canvas.create_text(x,y,text=text,font=font)

Tkinter 新手，经过大量研究后，我仍然无法找到有关使其正常工作的细节。

我也试过这个：

  while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            tk.update()
            ball1.draw()
            bat1.draw()
        else:
            game_over()

        time.sleep(0.02) 
main()

...在 Ball 类中包含以下内容

  def draw(self): 
        self.canvas.move(self.id,self.x,self.y) 
        pos=self.canvas.coords(self.id) 
        if pos[1] <=0: 
            self.y=6
            #we make a change here as well -alter the if statement to see if the ball has hit the bottom (equal or greater than canvas height), if so hit_bottom =True (as there is no more need to bounce the ball if the game is over!)
        if pos[3] >=self.canvas_height: 
            self.hit_bottom = True
            game_over()

这也不起作用：

错误： 画布未定义

可运行示例（完整代码）

from tkinter import *

import random
import time

class Game:
    def game_loop(self,canvas):
        if hit_bottom==True:
            self.draw_text(300,200,'You Lose')
    def draw_text(self,canvas,x,y,text,size='40'):
        font=('Helvetica',size)
        return self.canvas.create_text(x,y,text=text,font=font)

class Ball: 
    def __init__(self,canvas,bat,color):  
        self.canvas=canvas
        self.bat=bat 
        self.id=canvas.create_oval(30,30,50,50,fill=color) 
        self.canvas.move(self.id,100,200)
        starting_position=[-3,-2,-1,1,2,3] 
        random.shuffle(starting_position) 
        self.x = starting_position[0] 
        self.y = -3 
        self.canvas_height=self.canvas.winfo_height()
        self.canvas_width=self.canvas.winfo_width()
        #Add a hit_bottom object variable here..
        self.hit_bottom=False #...note we change the main loop at the bottom to include an if function that utilises this hit_bottom object variable


    def hit_bat(self,pos):
        bat_pos=self.canvas.coords(self.bat.id) 
        if pos[2] >=bat_pos[0] and pos[0] <=bat_pos[2]: 
            if pos[3]>=bat_pos[1] and pos[3] <= bat_pos[3]: 
                return True
        return False

    def draw(self): 
        self.canvas.move(self.id,self.x,self.y) 
        pos=self.canvas.coords(self.id) 
        if pos[1] <=0: 
            self.y=6
            #we make a change here as well -alter the if statement to see if the ball has hit the bottom (equal or greater than canvas height), if so hit_bottom =True (as there is no more need to bounce the ball if the game is over!)
        if pos[3] >=self.canvas_height: 
            self.hit_bottom = True


        if self.hit_bat(pos) ==True: 
            self.y=-6 
        if pos[0] <=0:
            self.x=6
        if pos[2]>=self.canvas_width:
            self.x=-6



class Pongbat():
    def __init__(self,canvas,color): 
        self.canvas=canvas
        self.id=canvas.create_rectangle(0,0,100,10,fill=color) 
        self.canvas.move(self.id,200,300)
        self.x=0
        self.canvas_width=self.canvas.winfo_width() 
        self.canvas.bind_all('<KeyPress-Left>',self.left_turn)
        self.canvas.bind_all('<KeyPress-Right>',self.right_turn)


    def draw(self): 
        self.canvas.move(self.id,self.x,0)
        pos=self.canvas.coords(self.id)
        if pos[0]<=0: 
            self.x=0
        if pos[2]>=self.canvas_width:
            self.x=0

    def left_turn(self,evt):
        self.x=-10 

    def right_turn(self,evt):
        self.x=10

def main():
    tk=Tk()
    tk.title("My 21st Century Pong Game")
    tk.resizable(0,0)
    tk.wm_attributes("-topmost",1)
    canvas=Canvas(tk,bg="white",width=500,height=400,bd=0,highlightthickness=0)
    canvas.pack()
    tk.update()

    bat1=Pongbat(canvas,'red') 
    ball1=Ball(canvas,bat1, 'green') 

    while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            tk.update()
            ball1.draw()
            bat1.draw()
        else:
            draw1=Game()
            draw1.draw_text(300,200,'Goodbye')

        time.sleep(0.02) 
main()

最终更新：

我尝试的最新方法是添加一个 init 方法，如下所示：

class Game:
    def __init__(self,canvas):
     self.canvas=canvas

    def game_loop(self,canvas):
        if hit_bottom==True:
            self.draw_text(300,200,'You Lose')
    def draw_text(self,canvas,x,y,text,size='40'):
        font=('Helvetica',size)
        return self.canvas.create_text(x,y,text=text,font=font)

和

 while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            tk.update()
            ball1.draw()
            bat1.draw()
        else:
            draw1=Game(canvas)
            #def draw_text(self,canvas,x,y,text,size='40'):
            draw1.draw_text(canvas,300,200,'Goodbye')

        time.sleep(0.02) 
main()

现在，第一个错误（关于没有画布或没有位置参数）消失了，但屏幕只是挂起。

Answer 1

屏幕在您上次更新时挂起，因为while 循环仍在运行，您没有得到/打破它。一旦满足您的条件，您应该 break 退出 while 循环。

这是您的代码，还有一些其他修复：

您的 right_turn 和 left_turn 方法似乎无法正常工作，但我会留给您解决。

from tkinter import *

import random
import time

class Game:
    def __init__(self, canvas):
        self.canvas=canvas

    def game_loop(self): ##No need to pass canvas since you are using the same canvas in __init__
        if hit_bottom==True:
            self.draw_text(300,200,'You Lose')
    def draw_text(self, x, y, text, size='40'): ##No need to pass canvas
        font=('Helvetica',size)
        print "Ok"
        return self.canvas.create_text(x,y,text=text,font=font)

class Ball: 
    def __init__(self,canvas,bat,color):  
        self.canvas=canvas
        self.bat=bat 
        self.id=self.canvas.create_oval(30,30,50,50,fill=color) ## self.canvas
        self.canvas.move(self.id,100,200)
        starting_position=[-3,-2,-1,1,2,3] 
        random.shuffle(starting_position) 
        self.x = starting_position[0] 
        self.y = -3 
        self.canvas_height=self.canvas.winfo_height()
        self.canvas_width=self.canvas.winfo_width()
        #Add a hit_bottom object variable here..
        self.hit_bottom=False #...note we change the main loop at the bottom to include an if function that utilises this hit_bottom object variable


    def hit_bat(self,pos):
        bat_pos=self.canvas.coords(self.bat.id) 
        if pos[2] >=bat_pos[0] and pos[0] <=bat_pos[2]: 
            if pos[3]>=bat_pos[1] and pos[3] <= bat_pos[3]: 
                return True
        return False

    def draw(self): 
        self.canvas.move(self.id,self.x,self.y) 
        pos=self.canvas.coords(self.id) 
        if pos[1] <=0: 
            self.y=6
            #we make a change here as well -alter the if statement to see if the ball has hit the bottom (equal or greater than canvas height), if so hit_bottom =True (as there is no more need to bounce the ball if the game is over!)
        if pos[3] >=self.canvas_height: 
            self.hit_bottom = True


        if self.hit_bat(pos) ==True: 
            self.y=-6 
        if pos[0] <=0:
            self.x=6
        if pos[2]>=self.canvas_width:
            self.x=-6



class Pongbat():
    def __init__(self,canvas,color): 
        self.canvas=canvas
        self.id=self.canvas.create_rectangle(0,0,100,10,fill=color) ## self.canvas
        self.canvas.move(self.id,200,300)
        self.x=0
        self.canvas_width=self.canvas.winfo_width() 
        self.canvas.bind_all('<KeyPress-Left>',self.left_turn)
        self.canvas.bind_all('<KeyPress-Right>',self.right_turn)


    def draw(self): 
        self.canvas.move(self.id,self.x,0)
        pos=self.canvas.coords(self.id)
        if pos[0]<=0: 
            self.x=0
        if pos[2]>=self.canvas_width:
            self.x=0

    def left_turn(self,evt):
        self.x =-10 

    def right_turn(self,evt):
        self.x =+10

def main():
    tk=Tk()
    tk.title("My 21st Century Pong Game")
    tk.resizable(0,0)
    tk.wm_attributes("-topmost",1)
    canvas=Canvas(tk,bg="white",width=500,height=400,bd=0,highlightthickness=0)
    canvas.pack()
    tk.update()

    bat1=Pongbat(canvas,'red') 
    ball1=Ball(canvas,bat1, 'green') 

    while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            tk.update()
            ball1.draw()
            bat1.draw()
        else:
            draw1=Game(canvas)
            #def draw_text(self,canvas,x,y,text,size='40'):
            draw1.draw_text(300,200,'Goodbye')
            break ## This stops the while loop

        time.sleep(0.02)
    tk.mainloop() # Keep the main window open
main()

Answer 2

在进行了一些更改后，其中大部分（如果不是全部）都用 cmets 表示，这里有一个脚本的可运行版本，它将在游戏结束时显示文本。

from tkinter import *

import random
import time

class Game:
    def __init__(self, canvas): # Added method.
        self.canvas=canvas
    def game_loop(self):  # Removed canvas parameter.
        if hit_bottom==True:
            self.draw_text(self.canvas,300,200,'You Lose')  # Added self.canvas arg
    def draw_text(self,canvas,x,y,text,size='40'):
        font=('Helvetica',size)
        return self.canvas.create_text(x,y,text=text,font=font)

class Ball:
    def __init__(self,canvas,bat,color):
        self.canvas=canvas
        self.bat=bat
        self.id=canvas.create_oval(30,30,50,50,fill=color)
        self.canvas.move(self.id,100,200)
        starting_position=[-3,-2,-1,1,2,3]
        random.shuffle(starting_position)
        self.x = starting_position[0]
        self.y = -3
        self.canvas_height=self.canvas.winfo_height()
        self.canvas_width=self.canvas.winfo_width()
        #Add a hit_bottom object variable here..
        self.hit_bottom=False #...note we change the main loop at the bottom to include an if function that utilises this hit_bottom object variable


    def hit_bat(self,pos):
        bat_pos=self.canvas.coords(self.bat.id)
        if pos[2] >=bat_pos[0] and pos[0] <=bat_pos[2]:
            if pos[3]>=bat_pos[1] and pos[3] <= bat_pos[3]:
                return True
        return False

    def draw(self):
        self.canvas.move(self.id,self.x,self.y)
        pos=self.canvas.coords(self.id)
        if pos[1] <=0:
            self.y=6
            #we make a change here as well -alter the if statement to see if the ball has hit the bottom (equal or greater than canvas height), if so hit_bottom =True (as there is no more need to bounce the ball if the game is over!)
        if pos[3] >=self.canvas_height:
            self.hit_bottom = True


        if self.hit_bat(pos) ==True:
            self.y=-6
        if pos[0] <=0:
            self.x=6
        if pos[2]>=self.canvas_width:
            self.x=-6



class Pongbat():
    def __init__(self,canvas,color):
        self.canvas=canvas
        self.id=canvas.create_rectangle(0,0,100,10,fill=color)
        self.canvas.move(self.id,200,300)
        self.x=0
        self.canvas_width=self.canvas.winfo_width()
        self.canvas.bind_all('<KeyPress-Left>',self.left_turn)
        self.canvas.bind_all('<KeyPress-Right>',self.right_turn)


    def draw(self):
        self.canvas.move(self.id,self.x,0)
        pos=self.canvas.coords(self.id)
        if pos[0]<=0:
            self.x=0
        if pos[2]>=self.canvas_width:
            self.x=0

    def left_turn(self,evt):
        self.x=-10

    def right_turn(self,evt):
        self.x=10

def main():
    tk=Tk()
    tk.title("My 21st Century Pong Game")
    tk.resizable(0,0)
    tk.wm_attributes("-topmost",1)
    canvas=Canvas(tk,bg="white",width=500,height=400,bd=0,highlightthickness=0)
    canvas.pack()
    tk.update()

    bat1=Pongbat(canvas,'red')
    ball1=Ball(canvas,bat1, 'green')

    while 1:
        if ball1.hit_bottom ==False: #this creates a condition - inside the loop it continues to check to see if the ball has hit (or not) the bottom of the screen
            ball1.draw()
            bat1.draw()
            tk.update()  # Allow screen to be updated (moved here after draw calls).
        else:
            draw1=Game(canvas)  # Added argument for new __init__() method.
            draw1.draw_text(canvas,300,200,'Goodbye')  # Added canvas arg.
            tk.update()  # Allow screen to be updated.
            canvas.after(3000)  # Added. Pause for a few seconds.
            return  # Terminate.

#        time.sleep(0.02)  # Shouldn't call sleep() in tkinter app.
        canvas.after(2)  # Use universal 'after()` method instead. Time in millisecs.
main()