java.lang.ClassCastException：在 Web-DriverWait 中使用 PageFactory 和 POM

Question

我在 selenium 中使用页面工厂模型来初始化 Web 元素。 我的代码中有等待操作，在将 Web 元素传递给我的等待操作时，它会抛出“ClassCastException”。 我无法找到解决方案，任何线索都会很棒。请建议我一些将 Page factory 对象转换为 WebElement 对象的方法。

@FindBy(how = How.XPATH, using = "//*[@id='menu-posts']/div[3]/div/ul/li[3]/a") public WebElement categories;

    public void menus() {
            try {
                loginTest();
                menuPosts.click();
                waitClick((WebElement) categories);
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                driver.quit();
            }
        }
    public void waitClick(WebElement element) {
        WebDriverWait wait = new WebDriverWait(driver, 20);
        wait.until(ExpectedConditions.visibilityOfElementLocated((By) element));
        element.click();
    }


**Exception trace:**

    java.lang.ClassCastException: com.sun.proxy.$Proxy7 cannot be cast to org.openqa.selenium.By
        at com.pageObject.categories.waitClick(categories.java:75)
        at com.pageObject.categories.menus(categories.java:54)
        at SeleniumFramework.com.framework.AppTest.viewPost(AppTest.java:37)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:108)
        at org.testng.internal.Invoker.invokeMethod(Invoker.java:661)
        at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:869)
        at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1193)
        at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:126)
        at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
        at org.testng.TestRunner.privateRun(TestRunner.java:744)
        at org.testng.TestRunner.run(TestRunner.java:602)
        at org.testng.SuiteRunner.runTest(SuiteRunner.java:380)
        at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:375)
        at org.testng.SuiteRunner.privateRun(SuiteRunner.java:340)
        at org.testng.SuiteRunner.run(SuiteRunner.java:289)
        at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
        at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
        at org.testng.TestNG.runSuitesSequentially(TestNG.java:1301)
        at org.testng.TestNG.runSuitesLocally(TestNG.java:1226)
        at org.testng.TestNG.runSuites(TestNG.java:1144)
        at org.testng.TestNG.run(TestNG.java:1115)
        at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:132)
        at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:236)
        at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:81)

Answer 1

当变量 categories 已经是 WebElement 时，您正在将变量 categories 转换为 WebElement。

改变这一行

waitClick((WebElement) categories);

到这里

waitClick(categories);

它应该摆脱异常。

您将遇到的另一个问题是您的waitClick() 函数将WebElement 转换为By。你不需要那里的演员表。更好的是，您应该在单击之前等待元素可单击。我会像下面这样重写它。

public void waitClick(WebElement element)
{
    new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(element)).click();
}

此外，Selenium 的创建者 Simon Stewart，recommends not using Page Factory。相反，我会将定位器存储在类的顶部，然后根据需要使用它们。我会重写整个事情如下。

public By categoriesLocator = By.xpath("//*[@id='menu-posts']/div[3]/div/ul/li[3]/a");

public void menus()
{
    try
    {
        loginTest();
        menuPosts.click(); // why aren't you using waitClick() here?
        waitClick(categoriesLocator);
    }
    catch (Exception e)
    {
        e.printStackTrace();
    }
    finally
    {
        driver.quit();
    }
}

public void waitClick(By locator)
{
    new WebDriverWait(driver, 20).until(ExpectedConditions.elementToBeClickable(locator)).click();
}