I have an utility method to switch to the required window as shown below
public class Utility
{
public static WebDriver getHandleToWindow(String title){
//parentWindowHandle = WebDriverInitialize.getDriver().getWindowHandle(); // save the current window handle.
WebDriver popup = null;
Set<String> windowIterator = WebDriverInitialize.getDriver().getWindowHandles();
System.err.println("No of windows : " + windowIterator.size());
for (String s : windowIterator) {
String windowHandle = s;
popup = WebDriverInitialize.getDriver().switchTo().window(windowHandle);
System.out.println("Window Title : " + popup.getTitle());
System.out.println("Window Url : " + popup.getCurrentUrl());
if (popup.getTitle().equals(title) ){
System.out.println("Selected Window Title : " + popup.getTitle());
return popup;
}
}
System.out.println("Window Title :" + popup.getTitle());
System.out.println();
return popup;
}
}
It will take you to desired window once title of the window is passed as parameter. In your case you can do.
Webdriver childDriver = Utility.getHandleToWindow("titleOfChildWindow");
and then again switch to parent window using the same method
Webdriver parentDriver = Utility.getHandleToWindow("titleOfParentWindow");
This method works effectively when dealing with multiple windows.