Listeners and EventFiringWebDriver in Selenium Webdriver

Before getting in we should talk about webdriverEvent listeners and EvebtFiringWebDriver interfaces.

1- WebDriverEventListener – This is an interface, which have some predefined methods so we will implement all of these methods.

2-EventFiringWebDriver- This is an class that actually fire Webdriver event.

Why we are using Webdriver Listeners
How to implement Listener in our Script
Step 1- Create a new Class that will implement WebDriverEventListener methods

In general for every action that runs we need to perform some activity logging ex. click, navigate etc and these are called events. So when ever we run script these actions logging will happen through these listeners and track them .

Take an example if you perform click then what should happen before click and after click.

To capture these events we will add listener that will perform this task for us.

Program for what is listeners in selenium webdriver

and call this as ActivityCapture

	public class ActivityCapture implements WebDriverEventListener {
	@Override
	public void afterChangeValueOf(WebElement arg0, WebDriver arg1) {
	}
	@Override
	public void afterClickOn(WebElement arg0, WebDriver arg1) {
	System.out.println("After click "+arg0.toString());
	}
	@Override
	public void afterFindBy(By arg0, WebElement arg1, WebDriver arg2) {
	System.out.println("After FindBy "+arg0.toString());
	}
	@Override
	public void afterNavigateBack(WebDriver arg0) {
	System.out.println("After navigating back "+arg0.toString());
	}
	@Override
	public void afterNavigateForward(WebDriver arg0) {
	System.out.println("After navigating forword "+arg0.toString());
	}
	@Override
	public void afterNavigateTo(String arg0, WebDriver arg1) {
	System.out.println("After navigating "+arg0.toString());
	System.out.println("After navigating "+arg1.toString());
	}
	@Override
	public void afterScript(String arg0, WebDriver arg1) {
	}
	@Override
	public void beforeChangeValueOf(WebElement arg0, WebDriver arg1) {
	}
	@Override
	public void beforeClickOn(WebElement arg0, WebDriver arg1) {
	System.out.println("before click "+arg0.toString());
	}
	@Override
	public void beforeFindBy(By arg0, WebElement arg1, WebDriver arg2) {
	System.out.println("before FindBY "+arg0.toString());
	}
	@Override
	public void beforeNavigateBack(WebDriver arg0) {
	System.out.println("Before navigating back "+arg0.toString());
	}
	@Override
	public void beforeNavigateForward(WebDriver arg0) {
	System.out.println("Before navigating Forword "+arg0.toString());
	}
	@Override
	public void beforeNavigateTo(String arg0, WebDriver arg1) {
	System.out.println("Before navigating "+arg0.toString());
	System.out.println("Before navigating "+arg1.toString());
	}
	@Override
	public void beforeScript(String arg0, WebDriver arg1) {
	}
	@Override
	public void onException(Throwable arg0, WebDriver arg1) {
	System.out.println("Testcase completed"+arg0.toString());
	System.out.println("Testcase completed"+arg1.toString());
	}
	}

view raw activitycapture.java hosted with ❤ by GitHub

for more details about webDriver listener click here : 

http://selenium.googlecode.com/svn@7074/trunk/docs/api/java/index.html

In above method we are just printing on console and this method will automatically called once click events fired.   

Step 2- Now create your simple script, create EventFiringWebDriver object, and pass your driver object.

EventFiringWebDriver myevent=new EventFiringWebDriver(driver);

Step 3- Create an object of the class who has implemented all the method of WebDriverEventListener so in our case ActivityCapture is a class who has implemented the same.

ActivityCapture handler=new ActivityCapture();

Step 4- Now register that event using register method and pass the object of ActivityCapture class

myevent.register(handler);

 Implementation of Webdriver listener

Now create a main java class as ListenersAndEventFiring 

In below sample scripts it will try to log in twitter account and for each actions the WebDriverEventListener and print on the screen. 

	public class ListenersAndEventFiring {
	public static void main(String[] args) {
	// TODO Auto-generated method stub
	System.out.println("Started Webdriver listener demo...");
	WebDriver driver=new FirefoxDriver();
	EventFiringWebDriver myevent=new EventFiringWebDriver(driver);
	ActivityCapture handler=new ActivityCapture();
	myevent.register(handler);
	myevent.navigate().to("https://twitter.com/login");
	myevent.findElement(By.xpath("//*[@id='page-container']/div/div[1]/form/fieldset/div[1]/input")).sendKeys("Test");
	myevent.findElement(By.xpath("//*[@id='page-container']/div/div[1]/form/fieldset/div[2]/input")).sendKeys("pwd");
	myevent.findElement(By.xpath("//*[@id='page-container']/div/div[1]/form/div[2]/button")).click();
	myevent.quit();
	myevent.unregister(handler);
	System.out.println("End of listener demo....");
	}
	}

view raw ListenernEventFiring.java hosted with ❤ by GitHub

Sample console output :

Started Webdriver listener demo...

Before navigating https://twitter.com/login

Before navigating FirefoxDriver: firefox on MAC (ec52d8fa-3c3c-5140-a30e-3daf2dc4536f)

After navigating https://twitter.com/login

After navigating FirefoxDriver: firefox on MAC (ec52d8fa-3c3c-5140-a30e-3daf2dc4536f)

before FindBY By.xpath: //*[@id='page-container']/div/div[1]/form/fieldset/div[1]/input

After FindBy By.xpath: //*[@id='page-container']/div/div[1]/form/fieldset/div[1]/input

before FindBY By.xpath: //*[@id='page-container']/div/div[1]/form/fieldset/div[2]/input

After FindBy By.xpath: //*[@id='page-container']/div/div[1]/form/fieldset/div[2]/input

before FindBY By.xpath: //*[@id='page-container']/div/div[1]/form/div[2]/button

After FindBy By.xpath: //*[@id='page-container']/div/div[1]/form/div[2]/button

before click [[FirefoxDriver: firefox on MAC (ec52d8fa-3c3c-5140-a30e-3daf2dc4536f)] -> xpath: //*[@id='page-container']/div/div[1]/form/div[2]/button]

After click [[FirefoxDriver: firefox on MAC (ec52d8fa-3c3c-5140-a30e-3daf2dc4536f)] -> xpath: //*[@id='page-container']/div/div[1]/form/div[2]/button]

End of listener demo....