切换至iframe时无法找到元素？

Question

1. 尝试在登录后通过奖励帐户通过Facebook登录我使iframe将用户与奖励帐户连接起来，正在使用窗口处理程序来查找从该框架弹出的Facebook，然后在登录后关闭，我返回iframe但无法当我切换回原位时，在父窗口（iframe）上找到一个元素
2. 错误是：

  

org.openqa.selenium.NoSuchElementException：无此类元素：无法   定位元素：{“方法”：“ xpath”，“选择器”：“ // * [@ id ='errorData']”}

1. 使用的代码

   public void amberLoginWithFacebook(String username, String pass) throws InterruptedException {
   
   actions.driver.switchTo().defaultContent();
   actions.driver.switchTo().frame(0);
   actions.clickOn(By.cssSelector(facebookBtn));
   Thread.sleep(2000);
   Set<String> handler = actions.driver.getWindowHandles();
   Iterator<String> loop = handler.iterator();
   String parentWindow = loop.next();
   String childWindow = loop.next();
   actions.driver.switchTo().window(childWindow);
   if (actions.driver.getTitle().toLowerCase().equals(facebookWindowTitle)) {
   actions.setText(By.cssSelector(facebookEmail), username);
   actions.setText(By.cssSelector(facebookPass), pass);
   actions.clickOn(By.cssSelector(facebookLoginBtn));
   Thread.sleep(2000);
   
   }
   
   actions.driver.switchTo().window(parentWindow);
   // i get the exception here 
   if (actions.waitUntil(By.xpath("NonlinkedAccountError"), "presenceOfElement") != null)
   {setCountryCode(properties.getProperty("CountryCode"));
   setPhone(properties.getProperty("phone"));
   actions.clickOn(By.xpath(defaultBtn));
   actions.clickOn(By.xpath(enterEmail));
   setEmail(properties.getProperty("email"));
   }
   

Screenshot for the frame