给上面的代码添加上 在屏幕上绘制出识别的图片周围绿线

可以使用cv2.rectangle()函数在屏幕截图中标出匹配位置并绘制绿色矩形框。具体来说，可以在WindowDetector类的detect()函数中加入以下代码：

for pt in zip(*loc[::-1]):
    cv2.rectangle(screenshot, pt, (pt[0] + self.w, pt[1] + self.h), (0, 255, 0), 2)

这段代码会在屏幕截图中标出匹配位置，并使用绿色的线条绘制矩形框。完整的代码如下：

import cv2 
import numpy as np 
import pyautogui 
import tkinter as tk 
from PIL import ImageTk, Image   

class WindowDetector:
    def __init__(self, template_path):
        self.template = cv2.imread(template_path, 0)
        self.w, self.h = self.template.shape[::-1]

    def detect(self):
        screenshot = pyautogui.screenshot()
        screenshot = np.array(screenshot)
        screenshot = cv2.cvtColor(screenshot, cv2.COLOR_BGR2GRAY)
        res = cv2.matchTemplate(screenshot, self.template, cv2.TM_CCOEFF_NORMED)
        threshold = 0.8
        loc = np.where(res >= threshold)
        for pt in zip(*loc[::-1]):
            cv2.rectangle(screenshot, pt, (pt[0] + self.w, pt[1] + self.h), (0, 255, 0), 2)
        return screenshot   

class App:
    def __init__(self, template_path):
        self.window_detector = WindowDetector(template_path)
        self.root = tk.Tk()
        self.root.title("Window Detector")
        self.root.geometry("800x600")
        self.canvas = tk.Canvas(self.root, width=800, height=600)
        self.canvas.pack()
        self.template = ImageTk.PhotoImage(Image.open(template_path))
        tk.Button(self.root, text="Detect", command=self.detect_window).pack()
        tk.Label(self.root, image=self.template).pack()
        self.root.mainloop()

    def detect_window(self):
        screenshot = self.window_detector.detect()
        img = ImageTk.PhotoImage(Image.fromarray(screenshot))
        self.canvas.create_image(0, 0, anchor=tk.NW, image=img)
        self.root.update_idletasks()

if __name__ == "__main__":
    app = App("template.png")

这样，运行程序后点击“Detect”按钮即可在屏幕截图中标出匹配位置并绘制绿色矩形框。