java - org.openqa.selenium.UnhandledAlertException: unexpected alert open

Question

I am using a Chrome Driver and trying to test a webpage.

Normally it runs fine, but sometimes I get exceptions:

 org.openqa.selenium.UnhandledAlertException: unexpected alert open
 (Session info: chrome=38.0.2125.111)
 (Driver info: chromedriver=2.9.248315,platform=Windows NT 6.1 x86) (WARNING: The server did not  provide any stacktrace information)
 Command duration or timeout: 16 milliseconds: null
 Build info: version: '2.42.2', revision: '6a6995d', time: '2014-06-03 17:42:30'
 System info: host: 'Casper-PC', ip: '10.0.0.4', os.name: 'Windows 7', os.arch: 'x86', os.version:  '6.1', java.version: '1.8.0_25'
 Driver info: org.openqa.selenium.chrome.ChromeDriver

Then I tried to handle the alert:

  Alert alt = driver.switchTo().alert();
  alt.accept();

But this time I received:

org.openqa.selenium.NoAlertPresentException 

I am attaching the screenshots of the alert:

I am not able to figure out what to do now. The problem is that I do not always receive this exception. And when it occurs, the test fails.

Answer 1

I had this problem too. It was due to the default behaviour of the driver when it encounters an alert. The default behaviour was set to "ACCEPT", thus the alert was closed automatically, and the switchTo().alert() couldn't find it.

The solution is to modify the default behaviour of the driver ("IGNORE"), so that it doesn't close the alert:

DesiredCapabilities dc = new DesiredCapabilities();
dc.setCapability(CapabilityType.UNEXPECTED_ALERT_BEHAVIOUR, UnexpectedAlertBehaviour.IGNORE);
d = new FirefoxDriver(dc);

Then you can handle it:

try {
    click(myButton);
} catch (UnhandledAlertException f) {
    try {
        Alert alert = driver.switchTo().alert();
        String alertText = alert.getText();
        System.out.println("Alert data: " + alertText);
        alert.accept();
    } catch (NoAlertPresentException e) {
        e.printStackTrace();
    }
}