在函数内部时，Python tkinter代码无法运行

问题描述

def display_rain():
    rain_image = Image.open("./images/rain_jpeg.jpg")
    rain_resized = rain_image.resize((250,250),Image.ANTIALIAS)
    rain_tk = ImageTk.PhotoImage(rain_resized)
    rain_label = tk.Label(root,image = rain_tk)
    rain_label.grid(row = 0,column = 0)
    rain_label.pack()

display_rain()

该代码在函数外部运行良好，但在函数内部似乎根本没有运行。我尝试重新启动Python并重命名该功能。

解决方法

您的图像正在被垃圾收集。这行得通。

import tkinter as tk
from PIL import Image,ImageTk


root = tk.Tk()
root.geometry("800x600")

#store all images in this dict so garbage collection will leave them alone
#it doesn't have to be named "images"; it just has to be a dict
images = dict()


def display_rain(row=0,column=0):
    #create and store the image if it doesn't exist
    if 'rain_tk' not in images:
        #unless you are making mips of this image you should probably  
        #~make it the proper size and get rid of the resize part
        image = Image.open("./images/rain_jpeg.jpg").resize((250,250),Image.ANTIALIAS)
        #you can add a name to reference the image by
        #this makes it cleaner than accessing the dict directly
        images['rain_tk'] = ImageTk.PhotoImage(image,name='rain')
        
    #make and return the label,in case you want to grid_forget it or change the image
    label = tk.Label(root,image='rain') #instead of image=images['rain_tk']
    label.grid(row=row,column=column)
    return label
    
#you can easily display this wherever you want by filling in the row and column arguments
#as an example,this would be displayed at row1 column2
rain_lbl = display_rain(1,2)
      
root.mainloop()