你可以显式地等待一个元素出现在网页上，然后才可以采取任何操作(如element.click()):

driver.get("http://somedomain/url_that_delays_loading");
WebElement myDynamicElement = (new WebDriverWait(driver, 10))
    .until(new ExpectedCondition<WebElement>() {
        @Override
        public WebElement apply(WebDriver d) {
            return d.findElement(By.id("myDynamicElement"));
        }
    }
);

这是我用于类似场景的方法，效果很好。

Ruby实现:

wait = Selenium::WebDriver::Wait.new(:timeout => 10)
wait.until {
    @driver.execute_script("return document.readyState;") == "complete" 
}

The best way to wait for page loads when using the Java bindings for WebDriver is to use the Page Object design pattern with PageFactory. This allows you to utilize the AjaxElementLocatorFactory which to put it simply acts as a global wait for all of your elements. It has limitations on elements such as drop-boxes or complex javascript transitions but it will drastically reduce the amount of code needed and speed up test times. A good example can be found in this blogpost. Basic understanding of Core Java is assumed.

http://startingwithseleniumwebdriver.blogspot.ro/2015/02/wait-in-page-factory.html

如何让Selenium在单击后等待页面加载提供了以下有趣的方法:

存储旧页面中对WebElement的引用。 点击链接。 继续调用WebElement上的操作，直到抛出StaleElementReferenceException。

示例代码:

WebElement link = ...;
link.click();
new WebDriverWait(webDriver, timeout).until((org.openqa.selenium.WebDriver input) ->
{
    try
    {
        link.isDisplayed();
        return false;
    }
    catch (StaleElementReferenceException unused)
    {
        return true;
    }
});

这似乎是WebDriver的一个严重限制。显然，等待一个元素并不意味着页面正在加载，特别是DOM可以完全构建(onready状态)，此时JS仍在执行，CSS和图像仍在加载。

我相信最简单的解决方案是在onload事件上设置一个JS变量，在所有东西初始化后，在Selenium中检查和等待这个JS变量。

SeleniumWaiter:

import com.google.common.base.Function;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.ui.WebDriverWait;

public class SeleniumWaiter {

      private WebDriver driver;

      public SeleniumWaiter(WebDriver driver) {
           this.driver = driver;
      }

      public WebElement waitForMe(By locatorname, int timeout){
           WebDriverWait wait = new WebDriverWait(driver, timeout);
           return wait.until(SeleniumWaiter.presenceOfElementLocated(locatorname));
      }

      public static Function<WebDriver, WebElement> presenceOfElementLocated(final By locator) {
            // TODO Auto-generated method stub
            return new Function<WebDriver, WebElement>() {
                 @Override
                 public WebElement apply(WebDriver driver) {
                      return driver.findElement(locator);
                 }
            };
      }
 }

对你来说:

_waiter = new SeleniumWaiter(_driver);

try {
   _waiter.waitForMe(By.xpath("//..."), 10);
} 
catch (Exception e) {
   // Error
}