我想编写截图应用程序，但无法制作GUI

Question

我试着用Python.When创建了一个截图应用程序，我运行了它的功能，它的工作和裁剪的大小很好。但是，我使用tkinter创建GUI并运行，它有问题。屏幕被捕获并首先出现，但我无法将其裁剪成我想要的大小。在那之后，我输入'q'，tkinter GUI出现，没有保存任何图像。有没有人可以帮我解决这个问题，以及如何选择文件来保存被捕获的图像？这是我的代码：

import cv2
import pyautogui
import tkinter as tk
from tkinter.filedialog import *
import os
import pyscreenshot as ImageGrab
from PIL import Image
import numpy as np

root = tk.Tk()

canvas1 = tk.Canvas(root, width=300, height=300)
canvas1.pack()

cropping = False
x_start, y_start, x_end, y_end = 0, 0, 0, 0
#event, x, y = 0


class takeScreenshot:
    im1 = pyautogui.screenshot()
    im1.save(r"monitor-1.png")
    image = cv2.imread('monitor-1.png')
    oriImage = image.copy()
    try:
        os.remove('monitor-1.png')
    except:
        pass

    def mouse_crop(self,event, x, y, flags, param=None):
        # grab references to the global variables
        global x_start, y_start, x_end, y_end, cropping
        # if the left mouse button was DOWN, start RECORDING
        # (x, y) coordinates and indicate that cropping is being
        if event == cv2.EVENT_LBUTTONDOWN:
            x_start, y_start, x_end, y_end = x, y, x, y
            cropping = True
        # Mouse is Moving
        elif event == cv2.EVENT_MOUSEMOVE:
            if cropping:
                x_end, y_end = x, y
        # if the left mouse button was released
        elif event == cv2.EVENT_LBUTTONUP:
            # record the ending (x, y) coordinates
            x_end, y_end = x, y
            cropping = False  # cropping is finished
            refPoint = [(x_start, y_start), (x_end, y_end)]
            if len(refPoint) == 2:  # when two points were found
                roi = self.oriImage[refPoint[0][1]:refPoint[1][1], refPoint[0] [0]:refPoint[1][0]]

                
                cv2.imwrite('d.png', roi)

    cv2.namedWindow("image")
    cv2.setMouseCallback("image", mouse_crop)
    while True:
        i = image.copy()
        if not cropping:
            cv2.imshow("image", image)
        elif cropping:
            cv2.rectangle(i, (x_start, y_start), (x_end, y_end), (255, 0, 0), 2)
            cv2.imshow("image", i)
        if cv2.waitKey(1) == ord('q'):
            break

def close_window():
    root.destroy()  # destroying the main window


myQuitButton = tk.Button(text="Quit", command=close_window, font=10)
canvas1.create_window(50, 50, window=myQuitButton)
myButton = tk.Button(text="Take Screenshot", command=takeScreenshot, font=10)
canvas1.create_window(150, 150, window=myButton)

root.mainloop()

Answer 1

类主体中的代码在该类定义后立即调用。如果您希望在创建类的实例时调用代码，请添加__init__方法：

...
class takeScreenshot:
    def __init__(self):
        im1 = pyautogui.screenshot()
        im1.save(r"monitor-1.png")
        image = cv2.imread('monitor-1.png')
        oriImage = image.copy()
        try:
            os.remove('monitor-1.png')
        except:
            pass
        cv2.namedWindow("image")
        cv2.setMouseCallback("image", self.mouse_crop)
        while True:
            i = image.copy()
            if not cropping:
                cv2.imshow("image", image)
            elif cropping:
                cv2.rectangle(i, (x_start, y_start), (x_end, y_end), (255, 0, 0), 2)
                cv2.imshow("image", i)
            if cv2.waitKey(1) == ord('q'):
                break

    def mouse_crop(self,event, x, y, flags, param=None):
        # grab references to the global variables
        global x_start, y_start, x_end, y_end, cropping
        # if the left mouse button was DOWN, start RECORDING
        # (x, y) coordinates and indicate that cropping is being
        if event == cv2.EVENT_LBUTTONDOWN:
            x_start, y_start, x_end, y_end = x, y, x, y
            cropping = True
        # Mouse is Moving
        elif event == cv2.EVENT_MOUSEMOVE:
            if cropping:
                x_end, y_end = x, y
        # if the left mouse button was released
        elif event == cv2.EVENT_LBUTTONUP:
            # record the ending (x, y) coordinates
            x_end, y_end = x, y
            cropping = False  # cropping is finished
            refPoint = [(x_start, y_start), (x_end, y_end)]
            if len(refPoint) == 2:  # when two points were found
                roi = self.oriImage[refPoint[0][1]:refPoint[1][1], refPoint[0] [0]:refPoint[1][0]]

                
                cv2.imwrite('d.png', roi)
...