一般来说，使用Selenium 2.0时，web驱动程序应该只在确定页面已加载后才将控制权返回给调用代码。如果没有，您可以调用waitforeleement，它循环调用findelement，直到找到它或超时(可以设置超时)。

对于使用java 8向前的程序员，可以使用下面的代码来使用显式等待等待页面加载。

JavascriptExecutor js = (JavascriptExecutor) driver;  
new WebDriverWait(driver, 10).until(webDriver ->
(js).executeScript("return document.readyState;").equals("complete"));

注意:在我上面的代码中使用Lambda表达式，它只在java 8的后续版本中可用。

对于使用低版本Java(即Java 8以下)的程序员，可以使用:

ExpectedCondition<Boolean> cond = new ExpectedCondition<Boolean>() {
    @Override
    public Boolean apply(WebDriver input) {
        JavascriptExecutor js = (JavascriptExecutor) driver; 
        return js.executeScript("return document.readyState;").equals("complete");
            }
        };
         
    new WebDriverWait(driver, 100).until(cond);

private static void checkPageIsReady(WebDriver driver) {
    JavascriptExecutor js = (JavascriptExecutor) driver;

    // Initially bellow given if condition will check ready state of page.
    if (js.executeScript("return document.readyState").toString().equals("complete")) {
        System.out.println("Page Is loaded.");
        return;
    }

    // This loop will rotate for 25 times to check If page Is ready after
    // every 1 second.
    // You can replace your value with 25 If you wants to Increase or
    // decrease wait time.
    for (int i = 0; i < 25; i++) {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
        }
        // To check page ready state.
        if (js.executeScript("return document.readyState").toString().equals("complete")) {
            break;
        }
    }
}

您可以尝试这段代码，让页面完全加载，直到找到元素为止。

public void waitForBrowserToLoadCompletely() {
    String state = null;
    String oldstate = null;
    try {
        System.out.print("Waiting for browser loading to complete");

        int i = 0;
        while (i < 5) {
            Thread.sleep(1000);
            state = ((JavascriptExecutor) driver).executeScript("return document.readyState;").toString();
            System.out.print("." + Character.toUpperCase(state.charAt(0)) + ".");
            if (state.equals("interactive") || state.equals("loading"))
                break;
            /*
             * If browser in 'complete' state since last X seconds. Return.
             */

            if (i == 1 && state.equals("complete")) {
                System.out.println();
                return;
            }
            i++;
        }
        i = 0;
        oldstate = null;
        Thread.sleep(2000);

        /*
         * Now wait for state to become complete
         */
        while (true) {
            state = ((JavascriptExecutor) driver).executeScript("return document.readyState;").toString();
            System.out.print("." + state.charAt(0) + ".");
            if (state.equals("complete"))
                break;

            if (state.equals(oldstate))
                i++;
            else
                i = 0;
            /*
             * If browser state is same (loading/interactive) since last 60
             * secs. Refresh the page.
             */
            if (i == 15 && state.equals("loading")) {
                System.out.println("\nBrowser in " + state + " state since last 60 secs. So refreshing browser.");
                driver.navigate().refresh();
                System.out.print("Waiting for browser loading to complete");
                i = 0;
            } else if (i == 6 && state.equals("interactive")) {
                System.out.println(
                        "\nBrowser in " + state + " state since last 30 secs. So starting with execution.");
                return;
            }

            Thread.sleep(4000);
            oldstate = state;

        }
        System.out.println();

    } catch (InterruptedException ie) {
        ie.printStackTrace();
    }
}

在我的例子中，我使用以下方法来了解页面加载状态。在我们的应用程序加载gif(s)是存在的，我听他们如下，以消除不必要的等待时间在脚本。

public static void processing(){ 
    WebDriverWait wait = new WebDriverWait(driver, 30);
    wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//div[@id='Msgpanel']/div/div/img")));
    wait.until(ExpectedConditions.invisibilityOfElementLocated(By.xpath("//div[@id='Msgpanel']/div/div/img")));
}

xpath在HTML DOM中定位gif的位置。 在此之后，您还可以实现您的动作方法单击。

public static void click(WebElement elementToBeClicked){
    WebDriverWait wait = new WebDriverWait(driver, 45);
    wait.until(ExpectedConditions.visibilityOf(element));
    wait.until(ExpectedConditions.elementToBeClickable(element)); 
    wait.ignoring(NoSuchElementException.class).ignoring(StaleElementReferenceException.class); elementToBeClicked.click(); 
 }

使用下面的代码，它是非常容易和简单的页面加载。

public void PageLoad(IWebDriver driver, By by)
{
    try
    {
        Console.WriteLine("PageLoad" + by);
        WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(30));
        wait.Until(ExpectedConditions.ElementIsVisible(by));
        wait = new WebDriverWait(driver, TimeSpan.FromSeconds(30)); // 30 seconds wait until element not found. 
        wait.Until(ExpectedConditions.ElementToBeClickable(by));


    }
    catch (Exception ex)
    {

        Console.WriteLine(ex.Message);
        Assert.Fail("Element not found!")
    }
}

我希望这对你有所帮助。