tkinter改进了随机显示图片

随机显示，还加了圆圈，这样感觉更好点。

from django.test import TestCase

# Create your tests here.
import random
import json
import time
import tkinter as tk
from tkinter import filedialog
from tkinter import LabelFrame
from tkinter import StringVar
from PIL import Image, ImageTk

# 方块大小
card_size = 120
# 间隙大小
gap_size = 2
# 绘图起点坐标
start_x = 400
start_y = 100
# 7 * 5 方格
x_grid = 7
y_grid = 5

# 打开文件，载入json文件
def open_file():
    xxx_name = filedialog.askopenfilename(title='打开文件',
                                          filetypes=[('json', '*.json'),
                                                     ('All Files', '*')])
    # 更新Label text变量
    var.set(xxx_name)
    with open(xxx_name, 'r') as load_f:
        global card_dict
        card_dict = json.load(load_f)

# 画圆
def draw_circle(cvs, x, y, r, **kwargs):
    return cvs.create_oval(x-r, y-r, x+r, y+r, **kwargs)

# 绘图
def draw_card():
    # 这个打开文件，用的是回调函数，我暂时也不知道如何不用这个全局变量
    global card_dict
    imgs_list = []
    for i in range(y_grid):
        y1 = start_y + i * card_size
        for j in range(x_grid):
            x1 = start_x + j * card_size
            # 解析json里对应的文件名
            image_num = card_dict[str(i+1)][str(j+1)]
            image_path = "images/{}.png".format(image_num[0].upper())
            # 载入图片
            img = Image.open(image_path)
            # 重定义大小
            img = img.resize((card_size-gap_size, card_size-gap_size), Image.BILINEAR)
            # 重定义旋转
            img = img.rotate(image_num[1])
            imgs = ImageTk.PhotoImage(img)
            # 先形成一个大列表，便于后面打乱了显示或成行成列显示
            card_pos = [x1 + gap_size, y1 + gap_size, imgs]
            imgs_list.append(card_pos)
    # 为了效果好，随机显示
    random.shuffle(imgs_list)
    for item in imgs_list:
        # 以nw左上角为基准点, 先大图出现，提示一下重点，加点透明GIF，就完美了
        # img_big = ImageTk.PhotoImage(item[3])
        # cv.create_image((item[0], item[1]), anchor='nw', image=img_big, tag='tmp_resize')
        cv.create_image((item[0], item[1]), anchor='nw', image=item[2])
        draw_circle(cv, item[0] + card_size / 2, item[1] + card_size / 2, 20, width=', outline="green",
                    tag='tmp_circle')
        cv.update()
        # 停一下
        time.sleep(0.5)
        # 删除圆圈，只作动画
        cv.delete('tmp_circle')
        # 不调用update，不会更新画布
        cv.update()
    time.sleep(10)

win = tk.Tk()
win.title('tkinter')
w = win.winfo_screenwidth()
h = win.winfo_screenheight()
win.geometry("%dx%d" % (w, h))
cv = tk.Canvas(win, bg='silver', width=w, height=h)

# 要更新label的text，要用var.set方法才行
var = StringVar()
var.set("...")
lab_fra = LabelFrame(win, height=200, width=300, text='选择文件')
lab_fra.pack(side='top', fill='both', expand=True)
btn_open = tk.Button(lab_fra, text='打开文件', command=open_file)
btn_open.grid(row=0, column=0)
btn_render = tk.Button(lab_fra, text='开始渲染', command=draw_card)
btn_render.grid(row=0, column=1)
text_label = tk.Label(lab_fra, textvariable=var)
text_label.grid(row=0, column=2)

# 画格子， 要算好横纵坐标
for i in range(y_grid):
    y1 = start_y + i * card_size
    for j in range(x_grid):
        x1 = start_x + j * card_size
        cv.create_rectangle(x1, y1, x1 + card_size, y1 + card_size)

cv.pack()
win.mainloop()