zoukankan      html  css  js  c++  java
  • 判断Selenium加载完成

    How do you make Selenium 2.0 wait for the page to load?
    
    You can also check pageloaded using following code
    
    IWait<IWebDriver> wait = new OpenQA.Selenium.Support.UI.WebDriverWait(driver, TimeSpan.FromSeconds(30.00));
    
     wait.Until(driver1 => ((IJavaScriptExecutor)driver).ExecuteScript("return document.readyState").Equals("complete"));
    2017年12月07日38分14秒
    
    Use class WebDriverWait
    
    Also see here
    
    You can expect to show some element. something like in C#:
    
    WebDriver _driver = new WebDriver();
    WebDriverWait _wait = new WebDriverWait(_driver, new TimeSpan(0, 1, 0));
    
    _wait.Until(d => d.FindElement(By.Id("Id_Your_UIElement"));
    2017年12月07日38分14秒
    
    If you set the implicit wait of the driver, then call the findElement method on an element you expect to be on the loaded page, the WebDriver will poll for that element until it finds the element or reaches the time out value.
    
    driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
    source: implicit-waits
    
    2017年12月07日38分14秒
    
    In general, with Selenium 2.0 the web driver should only return control to the calling code once it has determined that the page has loaded. If it does not, you can call waitforelemement, which cycles round calling findelement until it is found or times out (time out can be set).
    
    2017年12月07日38分14秒
    
    Ruby implementation:
    
    wait = Selenium::WebDriver::Wait.new(:timeout => 10)
    wait.until {
        @driver.execute_script("return document.readyState;") == "complete" 
    }
    2017年12月07日38分14秒
    
    You may remove the System.out line. It is added for debug purposes.
    
    WebDriver driver_;
    
    public void waitForPageLoad() {
    
        Wait<WebDriver> wait = new WebDriverWait(driver_, 30);
        wait.until(new Function<WebDriver, Boolean>() {
            public Boolean apply(WebDriver driver) {
                System.out.println("Current Window State       : "
                    + String.valueOf(((JavascriptExecutor) driver).executeScript("return document.readyState")));
                return String
                    .valueOf(((JavascriptExecutor) driver).executeScript("return document.readyState"))
                    .equals("complete");
            }
        });
    }
    2017年12月07日38分14秒
    
    You can also use the class: ExpectedConditions to explicitly wait for an element to show up on the webpage before you can take any action further actions
    
    You can use the ExpectedConditions class to determine if an element is visible:
    
    WebElement element = (new WebDriverWait(getDriver(), 10)).until(ExpectedConditions.visibilityOfElementLocated(By.cssSelector("input#houseName")));
    See ExpectedConditions class Javadoc for list of all conditions you are able to check.
    
    2017年12月07日38分14秒
    
    This seems to be a serious limitation of WebDriver. Obviously waiting for an element will not imply the page being loaded, in particular the DOM can be fully build (onready state) whereby JS is still executing and CSS and images are still loading.
    
    I believe the simplest solution is to set a JS variable upon the onload event after everything is initialized and check and wait for this JS variable in Selenium.
    
    2017年12月07日38分14秒
    
    All of these solutions are OK for specific cases, but they suffer from at least one of a couple of possible problems:
    
    They are not generic enough -- they want you to know, ahead of time, that some specific condition will be true of the page you are going to (eg some element will be displayed)
    
    They are open to a race condition where you use an element that is actually present on the old page as well as the new page.
    
    Here's my attempt at a generic solution that avoids this problem (in Python):
    
    First, a generic "wait" function (use a WebDriverWait if you like, I find them ugly):
    
    def wait_for(condition_function):
        start_time = time.time()
        while time.time() < start_time + 3:
            if condition_function():
                return True
            else:
                time.sleep(0.1)
        raise Exception('Timeout waiting for {}'.format(condition_function.__name__))
    Next, the solution relies on the fact that selenium records an (internal) id-number for all elements on a page, including the top-level <html> element. When a page refreshes or loads, it gets a new html element with a new ID.
    
    So, assuming you want to click on a link with text "my link" for example:
    
    old_page = browser.find_element_by_tag_name('html')
    
    browser.find_element_by_link_text('my link').click()
    
    def page_has_loaded():
        new_page = browser.find_element_by_tag_name('html')
        return new_page.id != old_page.id
    
    wait_for(page_has_loaded)
    For more Pythonic, reusable, generic helper, you can make a context manager:
    
    from contextlib import contextmanager
    
    @contextmanager
    def wait_for_page_load(browser):
        old_page = browser.find_element_by_tag_name('html')
    
        yield
    
        def page_has_loaded():
            new_page = browser.find_element_by_tag_name('html')
            return new_page.id != old_page.id
    
        wait_for(page_has_loaded)
    And then you can use it on pretty much any selenium interaction:
    
    with wait_for_page_load(browser):
        browser.find_element_by_link_text('my link').click()
    I reckon that's bulletproof! What do you think?
    
    More info in a blog post about it here
    
    2017年12月07日38分14秒
    
    If you want to wait for a specific element to load, you can use the isDisplayed() method on a RenderedWebElement :
    
    // Sleep until the div we want is visible or 5 seconds is over
    long end = System.currentTimeMillis() + 5000;
    while (System.currentTimeMillis() < end) {
        // Browsers which render content (such as Firefox and IE) return "RenderedWebElements"
        RenderedWebElement resultsDiv = (RenderedWebElement) driver.findElement(By.className("gac_m"));
    
        // If results have been returned, the results are displayed in a drop down.
        if (resultsDiv.isDisplayed()) {
          break;
        }
    }
    (Example from The 5 Minute Getting Started Guide)
    
    2017年12月07日38分14秒
    
    Imran's answer rehashed for Java 7:
    
        WebDriverWait wait = new WebDriverWait(driver, 30);
    
        wait.until(new ExpectedCondition<Boolean>() {
            public Boolean apply(WebDriver wdriver) {
                return ((JavascriptExecutor) driver).executeScript(
                    "return document.readyState"
                ).equals("complete");
            }
        });
    2017年12月07日38分14秒
    
    I'm surprised that predicates weren't the first choice as you typically know what element(s) you will next interact with on the page you're waiting to load. My approach has always been to build out predicates/functions like waitForElementByID(String id) and waitForElemetVisibleByClass(String className), etc. and then use and reuse these wherever I need them, be it for a page load or page content change I'm waiting on.
    
    For example,
    
    In my test class:
    
    driverWait.until(textIsPresent("expectedText");
    In my test class parent:
    
    protected Predicate<WebDriver> textIsPresent(String text){
        final String t = text;
        return new Predicate<WebDriver>(){
            public boolean apply(WebDriver driver){
                return isTextPresent(t);
            }
        };
    }
    
    protected boolean isTextPresent(String text){
        return driver.getPageSource().contains(text);
    }
    Though this seems like a lot, it takes care of checking repeatedly for you and the interval for how often to check can be set along with the ultimate wait time before timing out. Also, you will reuse such methods.
    
    In this example, the parent class defined and initiated the WebDriver driver and the WebDriverWait driverWait.
    
    I hope this helps.
    
    2017年12月07日38分14秒
    
    Use implicitly wait for wait of every element on page till given time.
    
    driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
    this wait for every element on page for 30 sec.
    
    Another wait is Explicitly wait or conditional wait in this wait until given condition.
    
    WebDriverWait wait = new WebDriverWait(driver, 40);
    WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.id("someid")));
    In id give static element id which is diffidently display on the page, as soon as page is load.
    
    2017年12月07日38分14秒
    
    /**
     * Call this method before an event that will change the page.
     */
    private void beforePageLoad() {
        JavascriptExecutor js = (JavascriptExecutor) driver;
        js.executeScript("document.mpPageReloaded='notYet';");
    }
    
    /**
     * Call this method after an event that will change the page.
     * 
     * @see #beforePageLoad
     * 
     *      Waits for the previous page to disappear.
     */
    private void afterPageLoad() throws Exception {
        (new WebDriverWait(driver, 10)).until(new Predicate<WebDriver>() {
    
            @Override
            public boolean apply(WebDriver driver) {
                JavascriptExecutor js = (JavascriptExecutor) driver;
                Object obj = js.executeScript("return document.mpPageReloaded;");
                if (obj == null) {
                    return true;
                }
                String str = (String) obj;
                if (!str.equals("notYet")) {
                    return true;
                }
                return false;
            }
        });
    }
    You can change from the document to an element, in the case of where only part of a document is being changed.
    
    This technique was inspired by the answer from sincebasic.
    
    2017年12月07日38分14秒
    
    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);
                     }
                };
          }
     }
    And to you use it:
    
    _waiter = new SeleniumWaiter(_driver);
    
    try {
       _waiter.waitForMe(By.xpath("//..."), 10);
    } 
    catch (Exception e) {
       // Error
    }
    2017年12月07日38分14秒
    
    You can explicitly wait for an element to show up on the webpage before you can take any action (like 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"));
    }});
    This is what I used for a similar scenario and it works fine.
    
    2017年12月07日38分14秒
    
    My simple way:
    
    long timeOut = 5000;
        long end = System.currentTimeMillis() + timeOut;
    
            while (System.currentTimeMillis() < end) {
    
                if (String.valueOf(
                        ((JavascriptExecutor) driver)
                                .executeScript("return document.readyState"))
                        .equals("complete")) {
                    break;
                }
            }
    2017年12月07日38分14秒
    
    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
    
    2017年12月07日38分14秒
    
    NodeJS Solution:
    
    In Nodejs you can get it via promises...
    
    If you write this code, you can be sure that the page is fully loaded when you get to the then...
    
    driver.get('www.sidanmor.com').then(()=> {
        // here the page is fully loaded!!!
        // do your stuff...
    }).catch(console.log.bind(console));
    If you write this code, you will navigate, and selenium will wait 3 seconds...
    
    driver.get('www.sidanmor.com');
    driver.sleep(3000);
    // you can't be sure that the page is fully loaded!!!
    // do your stuff... hope it will be OK...
    From Selenium documentation:
    
    this.get( url ) → Thenable
    
    Schedules a command to navigate to the given URL.
    
    Returns a promise that will be resolved when the document has finished loading.
    
    Selenium Documentation (Nodejs)
    
    2017年12月07日38分14秒
    
    You can use the below existing method to set the time for pageeLoadTimeout in below example if the page is taking more than 20 seconds to load , then it will throw an exception of page reload
    
     WebDriver driver = new FirefoxDriver();
    driver.manage().timeouts().pageLoadTimeout(20, TimeUnit.SECONDS)
    2017年12月07日38分14秒
    
    Explicitly wait or conditional wait in this wait until given condition.
    
     WebDriverWait wait = new WebDriverWait(wb, 60);
     wait.until(ExpectedConditions.elementToBeClickable(By.name("value")));
    This will wait for every web element for 60 seconds.
    
    Use implicitly wait for wait of every element on page till given time.
    
    driver.manage().timeouts().implicitlyWait(60, TimeUnit.SECONDS);
    This will wait for every web element for 60 seconds.
    
    Both works fine. But my personal favorite is Explicitly wait because it is more stable one
    
    2017年12月07日38分14秒
    
    You can use wait. there are basically 2 types of wait in selenium
    
    Implicit wait
    Explicit wait
    - Implicit wait
    
    This is very simple please see syntax below:
    
    driver.manage().timeouts().implicitlyWait(20, TimeUnit.SECONDS);
    - Explicit wait
    
    Explicitly wait or conditional wait in this wait until given condition is occurred.
    
    WebDriverWait wait = new WebDriverWait(driver, 40);
    WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.id("someid")));
    You can use other properties like visblityOf(), visblityOfElement()
    
    2017年12月07日38分14秒
    
    driver.asserts().assertElementFound("Page was not loaded",
    By.xpath("//div[@id='actionsContainer']"),Constants.LOOKUP_TIMEOUT);
    2017年12月07日38分14秒
    
    The easiest way is just wait for some element which will appear on loaded page.
    
    If you would like to click on some button already after page is loaded you could use await and click:
    
    await().until().at.most(20, TimeUnit.Seconds).some_element.isDisplayed(); // or another condition
    getDriver().find(some_element).click;
    2017年12月07日38分14秒
    
    How to get Selenium to wait for page load after a click provides the following interesting approach:
    
    Store a reference to a WebElement from the old page.
    Click the link.
    Keep on invoking operations on the WebElement until StaleElementReferenceException is thrown.
    Sample code:
    
    WebElement link = ...;
    link.click();
    new WebDriverWait(webDriver, timeout).until((org.openqa.selenium.WebDriver input) ->
    {
        try
        {
            link.isDisplayed();
            return false;
        }
        catch (StaleElementReferenceException unused)
        {
            return true;
        }
    });
    2017年12月07日38分14秒
    
    use a if condition and for any of the element present
    
    try {
        Thread.sleep(1000);
    } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    2017年12月07日38分14秒
    
    You can try this code to let the page load completely until element is found.
    
    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("
    Browser 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(
                            "
    Browser 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();
        }
    }
    2017年12月07日38分14秒
    
    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;
                }
            }
        }
    2017年12月07日38分14秒
    
    You can use this snippet of code for the page to load:
    
        IWait wait = new OpenQA.Selenium.Support.UI.WebDriverWait(driver,TimeSpan.FromSeconds(30.00));
        wait.Until(driver1 => ((IJavaScriptExecutor)driver).ExecuteScript("return document.readyState").Equals("complete"));
    Or you can use waiter for any element to be loaded and become visible/clickable on that page, most probably which is going to be load at the end of loading like:
    
        Wait.Until(ExpectedConditions.ElementToBeClickable(By.XPath(xpathOfElement));
        var element = GlobalDriver.FindElement(By.XPath(xpathOfElement));
        var isSucceededed = element != null;
    2017年12月07日38分14秒
    
    The best way I've seen is to utilize the stalenessOf ExpectedCondition, to wait for the old page to become stale.
    
    Example:
    
    WebDriver driver = new FirefoxDriver();
    WebDriverWait wait = new WebDriverWait(driver, 10);
    
    WebElement oldHtml = driver.findElement(By.tagName("html"));
    wait.until(ExpectedConditions.stalenessOf(oldHtml));
    It'll wait for ten seconds for the old HTML tag to become stale, and then throw an exception if it doesn't happen.
    
    2017年12月07日38分14秒
    

      

  • 相关阅读:
    Oracle 11g系列:函数与存储过程
    Oracle 11g系列:视图
    Oracle 11g系列:约束
    Oracle 11g系列:数据表对象
    Oracle 11g系列:数据库
    Oracle 11g系列:SQL Plus与PL/SQL
    Ext.util.TaskRunner定时执行任务
    MS SQL Server存储过程
    UML基础:用例图Use Case Diagram(1)
    UML基础系列:类图
  • 原文地址:https://www.cnblogs.com/c-x-a/p/7997584.html
Copyright © 2011-2022 走看看