In python, can locateCenterOnScreen be used with region?-CodePudding

There is a large picture including number 8.

First, I want to detect the large picture as below:

left, top, width, height = pyautogui.locateOnScreen('original.png', confidence=0.3)

Second, if the large picture is detected, then I want to narrow down to find the number 8.

x, y = pyautogui.locateCenterOnScreen('number8.png', confidence=0.8, region=(left, top, width, height))

Finally, I want to click the number 8

pyautogui.click(x, y)

This is my code, but it returns error below:

TypeError: cannot unpack non-iterable NoneType object

import time
import pyautogui

time.sleep(1)
left, top, width, height = pyautogui.locateOnScreen('original.png', confidence=0.3)
if left is None:
    print("Not Detected")
else:
    print("Detected")
    x, y = pyautogui.locateCenterOnScreen('number8.png', confidence=0.8, region=(left, top, width, height))
    if x is None:
        print("Error")
    else:
        print("Clicked")
        pyautogui.click(x, y)

CodePudding user response：

Yes locateCenterOnScreen can be used with region. That error you get is because pyautogui simply cannot find the object. And since there is no result, it cannot use iteration to assign variables to your x and y

this line here will never be true

if x is None: #

Because this line will throw an error if the object is not found

x, y = pyautogui.locateCenterOnScreen('number8.png', confidence=0.8, region=(left, top, width, height))