java - 有时找不到 Xpath 元素

Question

Boolean run = true;

        while(run)
        {
            if (nomore.contentEquals(tt))
                {
                driver.navigate().to("https://mettl.com/corporate/live-feed#/proctoringDashboard");
                Thread.sleep(750);
                driver.findElement(By.xpath("//label[@class='checkbox ng-binding']//input[@type='checkbox']")).click();
                driver.findElement(By.xpath("//button[contains(text(),'Authorize')]")).click();
                //Thread.sleep(1200);
                System.out.println("Not Available");

                }

            else
                {

                //Thread.sleep(10000);
                run = false;
                System.out.println("Available");
                break;                                  
                } 

        } 

这是我的错误

Nov 23, 2018 10:22:08 AM org.openqa.selenium.remote.DesiredCapabilities firefox
INFO: Using `new FirefoxOptions()` is preferred to `DesiredCapabilities.firefox()`
Starting ChromeDriver 2.43.600210 (68dcf5eebde37173d4027fa8635e332711d2874a) on port 11629
Only local connections are allowed.
Nov 23, 2018 10:22:13 AM org.openqa.selenium.remote.ProtocolHandshake createSession
INFO: Detected dialect: OSS

不可用无法使用无法使用无法使用无法使用无法使用无法使用无法使用无法使用无法使用不可用

Exception in thread "main" org.openqa.selenium.NoSuchElementException: no such element: Unable to locate element: {"method":"xpath","selector":"//label[@class='checkbox ng-binding']//input[@type='checkbox']"}

*** Element info: {Using=xpath, value=//label[@class='checkbox ng-binding']//input[@type='checkbox']}
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:214)
    at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:166)
    at org.openqa.selenium.remote.http.JsonHttpResponseCodec.reconstructValue(JsonHttpResponseCodec.java:40)
    at org.openqa.selenium.remote.http.AbstractHttpResponseCodec.decode(AbstractHttpResponseCodec.java:80)
    at org.openqa.selenium.remote.http.AbstractHttpResponseCodec.decode(AbstractHttpResponseCodec.java:44)
    at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)
    at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:83)
    at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:552)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:323)
    at org.openqa.selenium.remote.RemoteWebDriver.findElementByXPath(RemoteWebDriver.java:428)
    at org.openqa.selenium.By$ByXPath.findElement(By.java:353)
    at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:315)
    at automation.ExampleScanario.main(ExampleScanario.java:52)

这一行包含在 Automation.ExampleScanario.main(ExampleScanario.java:52)

driver.findElement(By.xpath("//label[@class='checkbox ng-binding']//input[@type='checkbox']")).click();

Answer 1

代替 Thread.sleep(750);您应该使用显式等待。这里的750是不到1秒，网页需要一些时间来加载，我们无法定义具体的时间。

WebDriverWait wait=new WebDriverWait(driver, 20);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("Your Element")).click());