Question

运行Selenium WebDriver 2.37.1

我在运行测试时遇到间歇性问题并收到以下错误：

org.openqa.selenium.NoSuchElementException: no such element

有时测试会通过，大部分时间都会失败。下面是stacktrace：

org.openqa.selenium.NoSuchElementException: no such element  
(Session info: chrome=31.0.1650.57)
(Driver info:
chromedriver=2.6.232923,platform=Windows NT 6.1 SP1 x86_64) 
(WARNING:
The server did not provide any stacktrace information) 
Command duration or timeout: 10.04 seconds 
For documentation on this error, please visit:
http://seleniumhq.org/exceptions/no_such_element.html 
Build info:
version: '2.34.0', revision:
'11cd0ef93615408e0b6b3bfa28defe125906461a', time: '2013-08-06
11:43:14' 
System info: os.name: 'Windows 7', os.arch: 'amd64',
os.version: '6.1', java.version: '1.7.0_45' 
Session ID:
2375dca8adea8bb6962b0c87861cdd59 
Driver info:
org.openqa.selenium.chrome.ChromeDriver 
Capabilities

以下是我执行测试的代码：

@Test
public void loginPage(){

    chrome.get("http://thisisafakeurl.com");
    //entering username
    WebElement usernameField = chrome.findElement(By.cssSelector("input[type='text'][id='usernameInput']"));
        usernameField.sendKeys("fakeusername");
    //entering password
    WebElement passwordField = chrome.findElement(By.cssSelector("input[id='passwordInput']"));
        passwordField.sendKeys("fakepassword");
    //clicking submit button
    chrome.findElement(By.cssSelector("input#loginBtn.rightButton")).click();

    chrome.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);

    //asserting a css selector. Not really needed. Just thrown in to learn.
   // WebElement blankProjectLocator = chrome.findElement(By.cssSelector("li.iconGridItem[data-id='5']"));
   // Assert.assertEquals("5", blankProjectLocator.getAttribute("data-id"));

    //Clicking the Blank Project button

    Actions actions = new Actions(chrome);
    WebElement item1 = chrome.findElement(By.xpath("//*[@id=\"templateGrid\"]/li[2]/img[1]"));
    WebElement item2 = chrome.findElement(By.xpath("//*[@id=\"templateGrid\"]/li[2]/img[2]"));
    WebElement item3 = chrome.findElement(By.xpath("//*[@id=\"templateGrid\"]/li[2]/header/span"));
    WebElement item4 = chrome.findElement(By.xpath("//*[@id=\"templateGrid\"]/li[2]"));

    actions.moveToElement(item4)
           .moveToElement(item1)
           .moveToElement(item2)
           .moveToElement(item3)
           .click().build().perform();

    chrome.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);





    //Dragging the Click Area component onto the canvas
    WebElement listContainer = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div"));
    WebElement componentList = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul"));
    WebElement clickArea = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[1]"));
    WebElement arrowHead = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[1]/div[1]"));
    WebElement imageHolderClickArea = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[1]/div[1]/div"));
    WebElement componentNameClickArea = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[1]/div[2]"));


    WebElement canvas = chrome.findElement(By.xpath("//*[@id=\"page-c3\"]"));

    actions.moveToElement(listContainer)
           .moveToElement(componentList)
           .clickAndHold(clickArea)
           .moveToElement(arrowHead)
           .moveToElement(imageHolderClickArea)
           .moveToElement(componentNameClickArea)
           .moveToElement(canvas)
           .release().perform();

    chrome.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);






    //Dragging the close button onto the canvas

    WebElement listContainerClose = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div"));
    WebElement componentListClose = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul"));
    WebElement closeButton = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[2]"));
    WebElement componentThumb = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[2]/div[1]"));
    WebElement imageHolderCloseButton = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[2]/div[1]/div"));
    WebElement componentNameCloseButton = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[2]/div[2]"));

    WebElement canvas1 = chrome.findElement(By.xpath("//*[@id=\"page-c3\"]"));

    actions.clickAndHold(closeButton)
            .moveToElement(listContainerClose)
            .moveToElement(componentListClose)
            .moveToElement(componentThumb)
            .moveToElement(imageHolderCloseButton)
            .moveToElement(componentNameCloseButton)
            .moveToElement(canvas1)
            .release().perform();

    //WebElement xAxisClose = chrome.findElement(By.xpath("//*[@id=\"c358\"]"));
    //xAxisClose.clear();
    //xAxisClose.sendKeys("240");

    //WebElement yAxisClose = chrome.findElement(By.xpath("//*[@id=\"c359\"]"));
    //yAxisClose.clear();
    //yAxisClose.sendKeys("5");






    //Dragging the video component onto the canvas

    WebElement listContainerVideo = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div"));
    WebElement componentListVideo = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul"));
    WebElement videoComponent = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[3]"));
    WebElement componentThumbVideo = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[3]/div[1]"));
    WebElement componentNameVideo = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[3]/div[2]"));

    WebElement canvas2 = chrome.findElement(By.xpath("//*[@id=\"page-c3\"]"));

    actions.clickAndHold(videoComponent)
            .moveToElement(listContainerVideo)
            .moveToElement(componentListVideo)
            .moveToElement(componentThumbVideo)
            .moveToElement(componentNameVideo)
            .moveToElement(canvas2)
            .release().perform();


    chrome.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);






    //Dragging the Text component onto the canvas

    WebElement listContainerText = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div"));
    WebElement componentListText = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul"));
    WebElement textComponent = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[4]"));
    WebElement componentThumbText = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[4]/div[1]"));
    WebElement componentNameText = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div/ul/li[4]/div[2]"));

    WebElement canvas3 = chrome.findElement(By.xpath("//*[@id=\"page-c3\"]"));

    actions.clickAndHold(textComponent)
            .moveToElement(listContainerText)
            .moveToElement(componentListText)
            .moveToElement(componentThumbText)
            .moveToElement(componentNameText)
            .moveToElement(canvas3)
            .release().perform();

stacktrace中的可点击链接指向以下代码行：

 WebElement listContainer = chrome.findElement(By.xpath("//*[@id=\"componentsDiv\"]/div/div/div"));

所以在测试之前可以点击Blank Project按钮。

从我的调查看来，我可能会遇到一些同步问题，因为它是间歇性的。我是否需要包装try / catch异常而不是超时等待？或者我将这些放在我的代码中不正确的地方？

任何人都可以帮助或建议我可能出错的地方吗？

Answer 1

我猜您的测试有时会因以下声明而失败

chrome.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);

只需在测试开始时放置一次超时代码，然后删除所有其他实例。

 chrome.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);

Answer 2

正如Yuvaraj HK所提到的那样，在代码中使用隐式等待就足够了。它会隐含地等待你在代码中找到的每个元素。

chrome.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);

但是尽量保持隐含的等待时间尽可能低，因为这可能会增加代码执行时间..

在某些情况下，元素可能需要超过30秒才能看到，显式等待可以在这种情况下使用。

WebDriverWait some_element = new WebDriverWait(driver,100); 
some_element.until(ExpectedConditions.visibilityOfElementLocated(By.id("id_of_some_element")));
//do anything you want with some_element

我强烈建议在{x}上使用cssSelectors。 This article might help。
即使使用xpath，也请尝试使用较短的路径。 使用ID不是到达元素的唯一方式。其父级可能具有唯一的类名称或其他属性，您可以使用这些属性创建有效的xpaths或cssSelectors。

Answer 3

是的......所以我设法解决了这里发生的事情。当我使用IntelliJ时，似乎我需要告诉它调用每个方法的顺序。所以加入 @FixMethodOrder(MethodSorters.NAME_ASCENDING)并在我的第一个方法上放置'a'，然后在我的第二个方法上放置'b'（我将问题中粘贴的代码分解为方法）等等，它按顺序运行方法等待每种方法：try { Thread.sleep(10000); } catch (InterruptedException e) { e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates. }

Answer 4

尝试在Windows Server 2003上测试IE7时遇到了同样的问题。我通过删除Internet Explorer增强安全配置来修复它。在Server 2003上，您可以通过执行以下操作来修复它：

打开控制面板
打开“添加或删除程序”
打开“添加/删除Windows组件”（位于左侧边栏）
取消选中Internet Explorer增强安全配置
点击下一步
一直到最后
重新启动Internet Explorer

如果使用Server 2008或2012，则步骤将有所不同，但目标是相同的。

Answer 5

你打开一个新窗口了吗？如果是，您需要使驱动程序切换到新窗口，以下代码由我测试：

String currentWindow = driver.getWindowHandle();// get handle of current window
Set<String> handles = driver.getWindowHandles();// get handle of all windows
Iterator<String> it = handles.iterator();
while (it.hasNext()) {
if (currentWindow == it.next()) {
continue;
}
driver = driver.switchTo().window(it.next());// switch to new window

//business action
//xxxxxxx
}
driver.switchTo().window(currentWindow);//switch back to original window

Answer 6

尝试使用SeleniumWait 库：

SeleniumWait.withDriver(driver).withTimeOut(15).forElementToClick(element);

Answer 7

可能是浏览器问题。我遇到了这个问题，并尝试了各种措施对其进行修复，但是直到浏览器的“缩放”百分比固定为100％时，它才起作用。这听起来可能简单而有趣，但对我有用。

org.openqa.selenium.NoSuchElementException：没有这样的元素

7 个答案: