Selenium NoAlertPresentException

Question

I'm trying to handle dialog (Ok Cancel type) with selenium WebDriver. So my aim is to click "Ok" button.

Scenario is:

1. Click button for invoking dialog

   button.click();

2. Try to accept

   webDriver.switchTo().alert().accept();

But I'm always getting NoAlertPresentException and seeing that dialog closes almost immediately. It seems to me that Selenium automatically closes dialog and when I want to accept, there is nothing to accept.

I'm sorry for my bad English.

Answer 1

The usual cause of this issue is that Selenium is too quick and tries to accept an alert that has not yet been opened by the browser. This can be simply fixed by an explicit wait:

button.click();
WebDriverWait wait = new WebDriverWait(driver, 5);
Alert alert = wait.until(ExpectedConditions.alertIsPresent());
alert.accept();

Answer 2

Step 1:
    public boolean isAlertPresent(){
            boolean foundAlert = false;
            WebDriverWait wait = new WebDriverWait(driver, 0 /*timeout in seconds*/);
            try {
                wait.until(ExpectedConditions.alertIsPresent());
                foundAlert = true;
                System.out.println("isAlertPresent : " +foundAlert);
            } catch (TimeoutException eTO) {
                foundAlert = false;
                System.out.println("isAlertPresent : " +foundAlert);
            }
            return foundAlert;
        }

Step 2:
public boolean tocheck_POP_Dialog()
    {   Alert alert;
        try
        {   
            alert=driver.switchTo().alert();


        }
        catch(NoSuchElementException elementException)
        {   
            return false;
        }

        alert.accept(); //Close Alert popup


        return true;
    }




Step 3 :
if(dummyPage.isAlertPresent())
                {
                    dummyPage.tocheck_POP_Dialog();
                }