预期条件失败：正在等待By.xpath定位的元素的可见性

Question

我试图单击alibaba.com网站上的“登录”链接

这是我的测试用例：

public class TestCase {

    public static void main(String[] args) throws InterruptedException {
        // TODO Auto-generated method stub

        String URL = "http://www.alibaba.com/";
        WebDriver driver;
        System.setProperty("webdriver.chrome.driver",
                "D:\\chromedriver_win32\\chromedriver.exe");
        driver = new ChromeDriver();
        driver.get(URL);
        Thread.sleep(2000);
        SignIn.SignIn_click(driver).click();
    }

}

这是定位Web元素的对象类

package PageObjects;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;

public class SignIn {


    private static WebElement element = null;

    public static WebElement SignIn_click(WebDriver driver) {
        element = (new WebDriverWait(driver, 10)).until(ExpectedConditions
                .visibilityOfElementLocated(By
                        .xpath("//a[@data-val='ma_signin']")));
        element = driver.findElement(By
                .xpath("//a[@data-val='ma_signin']"));
        return element;

    }

}

但是，当我运行此代码时，总是会遇到以下异常：

Exception in thread "main" org.openqa.selenium.TimeoutException: Expected condition failed: waiting for visibility of element located by By.xpath: //a[@data-val='ma_signin'] (tried for 10 second(s) with 500 MILLISECONDS interval)
    Build info: version: 'unknown', revision: '86a5d70', time: '2017-02-16 07:47:51 -0800'
    System info: host: 'ANUM-PC', ip: '172.16.11.162', os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.8.0_121'
    Driver info: org.openqa.selenium.chrome.ChromeDriver
    Capabilities [{applicationCacheEnabled=false, rotatable=false, mobileEmulationEnabled=false, networkConnectionEnabled=false, chrome={chromedriverVersion=2.30.477700 (0057494ad8732195794a7b32078424f92a5fce41), userDataDir=C:\Users\Anum\AppData\Local\Temp\scoped_dir1716_14873}, takesHeapSnapshot=true, pageLoadStrategy=normal, databaseEnabled=false, handlesAlerts=true, hasTouchScreen=false, version=59.0.3071.115, platform=XP, browserConnectionEnabled=false, nativeEvents=true, acceptSslCerts=true, locationContextEnabled=true, webStorageEnabled=true, browserName=chrome, takesScreenshot=true, javascriptEnabled=true, cssSelectorsEnabled=true, unexpectedAlertBehaviour=}]
    Session ID: d0c1083c113270bd4ded08846544878e
        at org.openqa.selenium.support.ui.WebDriverWait.timeoutException(WebDriverWait.java:80)
        at org.openqa.selenium.support.ui.FluentWait.until(FluentWait.java:257)
        at PageObjects.SignIn.SignIn_click(SignIn.java:15)
        at AutomationFramework.TestCase.main(TestCase.java:24)

请帮我。

Answer 1

请尝试以下操作：

package PageObjects;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;

public class SignIn {

    private static WebElement element = null;
    public static WebElement SignIn_click(WebDriver driver) throws InterruptedException {
    element = driver.findElement(By.xpath("id('J_SC_header')/header/div[2]//span[1]/a[@data-val='ma_signin']"));

    while (!isDisplayed(element)) 
    {
        Thread.sleep(3000);
        System.out.println("Element is not visible yet");
    }
    return element;

    }
    public static boolean isDisplayed(WebElement element) {
        try {
            if(element.isDisplayed())
                return element.isDisplayed();
            }catch (NoSuchElementException ex) {
            return false;
        }
        return false;
    }
}