问题：
使用 https://testerhome.com/topics/11720 的框架，通过 uiautomator2 识别元素，失败。

经过简单的查看日志，在页面更新后，需要刷新页面缓存才对，实际上切换 uiautomator2 框架没有这个操作。

操作
工程代码： https://github.com/leila-wu/pythonAppium 。执行 Runner 下的 runner.py，调用 HomeTest.py 执行用例。

日志与描述：
切换 desired_caps['automationName'] = 'Appium'。识别元素成功。 重点看到Failed to locate element. Clearing Accessibility cache and retrying.。取值失败，有清除缓存处理

该场景的其他元素获取正常，需要重新识别的元素，是页面小范围刷新。比如点击 A 按钮新增的 B 展示后，元素 B 获取失败

[debug] [W3C] Calling AppiumDriver.findElement() with args: ["id","com.thinkive.future.dev.standard:id/tv_optional_edit","6757fcaa-b7b8-4ccf-8486-2d538f86d617"]
[debug] [BaseDriver] Valid locator strategies for this request: xpath, id, class name, accessibility id, -android uiautomator
[debug] [BaseDriver] Waiting up to 0 ms for condition
[debug] [AndroidBootstrap] Sending command to android: {"cmd":"action","action":"find","params":{"strategy":"id","selector":"com.thinkive.future.dev.standard:id/tv_optional_edit","context":"","multiple":false}}
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Got data from client: {"cmd":"action","action":"find","params":{"strategy":"id","selector":"com.thinkive.future.dev.standard:id/tv_optional_edit","context":"","multiple":false}}
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Got command of type ACTION
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Got command action: find
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Finding 'com.thinkive.future.dev.standard:id/tv_optional_edit' using 'ID' with the contextId: '' multiple: false
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Using: UiSelector[INSTANCE=0, RESOURCE_ID=com.thinkive.future.dev.standard:id/tv_optional_edit]
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Failed to locate element. Clearing Accessibility cache and retrying.
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Finding 'com.thinkive.future.dev.standard:id/tv_optional_edit' using 'ID' with the contextId: '' multiple: false
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Using: UiSelector[INSTANCE=0, RESOURCE_ID=com.thinkive.future.dev.standard:id/tv_optional_edit]
[debug] [AndroidBootstrap] [BOOTSTRAP LOG] [debug] Returning result: {"status":0,"value":{"ELEMENT":"13"}}
[debug] [AndroidBootstrap] Received command result from bootstrap
[debug] [W3C] Responding to client with driver.findElement() result: {"ELEMENT":"13"}
[HTTP] <-- POST /wd/hub/session/6757fcaa-b7b8-4ccf-8486-2d538f86d617/element 200 214 ms - 88

切换 desired_caps['automationName'] = 'uiautomator2'。元素识别失败（端口随机处理。）

[debug] [W3C] Calling AppiumDriver.findElement() with args: ["id","com.thinkive.future.dev.standard:id/tv_optional_edit","8c510efb-4426-45bc-84eb-971441239f1e"]
[debug] [BaseDriver] Valid locator strategies for this request: xpath, id, class name, accessibility id, -android uiautomator
[debug] [BaseDriver] Waiting up to 0 ms for condition
[debug] [JSONWP Proxy] Proxying [POST /element] to [POST http://localhost:4754/wd/hub/session/b6d92bbf-10c9-475b-b382-ffb975645773/element] with body: {"strategy":"id","selector":"com.thinkive.future.dev.standard:id/tv_optional_edit","context":"","multiple":false}
[HTTP] <-- POST /wd/hub/session/8c510efb-4426-45bc-84eb-971441239f1e/element 404 28 ms - 1119
[HTTP] 

检查代码

WebDriverWait(self.driver, t).until(lambda x: self.elements_by(mOperate))  # 操作元素是否存在

# 封装常用的标签
    def elements_by(self, mOperate):
        elements = {
            BE.find_element_by_id: lambda: self.driver.find_element_by_id(mOperate["element_info"]),
            BE.find_element_by_xpath: lambda: self.driver.find_element_by_xpath(mOperate["element_info"]),
            BE.find_element_by_css_selector: lambda: self.driver.find_element_by_css_selector(mOperate['element_info']),
            BE.find_element_by_class_name: lambda: self.driver.find_element_by_class_name(mOperate['element_info']),
            BE.find_elements_by_id: lambda: self.driver.find_elements_by_id(mOperate['element_info']),

        }
        return elements[mOperate["find_type"]]()

脚本配置：

- element_info: com.thinkive.future.dev.standard:id/tv_optional_edit
  find_type: id
  operate_type: click
  info: 点击编辑按钮