robot framework Selenium2library wait小问题

最近在使用selenium2Library时，用到其中的 Wait Until Page函数，因我们的网页相对比较敏感，经常获取不到，不明觉历

看看源码吧，如下：

def wait_until_page_contains_element(self, locator, timeout=None, error=None):
        """Waits until element specified with `locator` appears on current page.

        Fails if `timeout` expires before the element appears. See
        `introduction` for more information about `timeout` and its
        default value.

        `error` can be used to override the default error message.

        See also `Wait Until Page Contains`, `Wait For Condition`,
        `Wait Until Element Is Visible` and BuiltIn keyword `Wait Until
        Keyword Succeeds`.
        """
        if not error:
            error = "Element '%s' did not appear in <TIMEOUT>" % locator
        self._wait_until(timeout, error, self._is_element_present, locator)

核心的等待函数在这里

def _wait_until_no_error(self, timeout, wait_func, *args):
        timeout = robot.utils.timestr_to_secs(timeout) if timeout is not None else self._timeout_in_secs
        maxtime = time.time() + timeout
        while True:
            timeout_error = wait_func(*args)
            if not timeout_error: return
            if time.time() > maxtime:
                raise AssertionError(timeout_error)
            time.sleep(0.2)

。。。。

函数中，写死等待0.2秒，还没有参数可以改。太暴力。

再来看看selenium原生的webdriverWait是怎么写的

    def until(self, method, message=''):
        """Calls the method provided with the driver as an argument until the 
        return value is not False."""
        screen = None
        stacktrace = None

        end_time = time.time() + self._timeout
        while True:
            try:
                value = method(self._driver)
                if value:
                    return value
            except self._ignored_exceptions as exc:
                screen = getattr(exc, 'screen', None)
                stacktrace = getattr(exc, 'stacktrace', None)
            time.sleep(self._poll)
            if time.time() > end_time:
                break
        raise TimeoutException(message, screen, stacktrace)

从源码中可以看出，等待时间可以自定义，except除了元素不可见，也还可以加自定义的错误。比selenium2library更好用