java - Selenium 使用 JavascriptExecutor 等待页面完全加载

Question

给定一个网站，页面上有 AJAX 组件，我需要等到整个页面完全加载。

这是我使用 JavascriptExecutor 检查 document.readyState 的等待方法:

public void waitForLoading2() {
        WebDriverWait wait = new WebDriverWait(driver, timeOut);
        if(!driver.findElements(By.xpath("//*[@id='wait'][contains(@style, 'display: block')]")).isEmpty()) {
            wait.until(ExpectedConditions.presenceOfElementLocated(By.xpath("//*[@id='wait'][contains(@style, 'display: none')]")));
        }

            ExpectedCondition<Boolean> expectation = new
                    ExpectedCondition<Boolean>() {
                        public Boolean apply(WebDriver driver) {
                            return ((JavascriptExecutor) driver).executeScript("return document.readyState").toString().equalsIgnoreCase("complete");
                        }
                    };
            wait.until(expectation);

    }

有时会失败并显示以下错误消息:

org.openqa.selenium.JavascriptException: JavaScript error (WARNING: The server did not provide any stacktrace information)

我在这里错过了什么？我的假设是 document.readyState 很常见并且始终可以检查。

谢谢

Answer 1

还有更多complex options ，比如这个

public static void waitForAjax(WebDriver driver, String action) {
       driver.manage().timeouts().setScriptTimeout(5, TimeUnit.SECONDS);
       ((JavascriptExecutor) driver).executeAsyncScript(
               "var callback = arguments[arguments.length - 1];" +
                       "var xhr = new XMLHttpRequest();" +
                       "xhr.open('POST', '/" + action + "', true);" +
                       "xhr.onreadystatechange = function() {" +
                       "  if (xhr.readyState == 4) {" +
                       "    callback(xhr.responseText);" +
                       "  }" +
                       "};" +
                       "xhr.send();");
}

按顺序

to wait till the whole page is fully loaded

但是下面的方法对我有用 - 我检查是否有正在进行的 AJAX 调用并等待这些调用完成:

JavascriptExecutor js = (JavascriptExecutor) driverjs;
js.executeScript("return((window.jQuery != null) && (jQuery.active === 0))").equals("true");