title: Selenium waitforpopup
body: <p>How to stop the selenium server until a popup opens? </p>
  
  <p>We have <code>selenium.waitForPageToLoad</code> to stop the server until the Page Loads. But is there any way to stop it for Popup? </p>
  
  <p>I tried it with <code>selenium.WaitForPopup</code>, but I can't find popup id. Because I created a popup box with div element(whose id is popup_container).</p>
  
  <p>And I tried the following code:</p>
  
  <pre><code>selenium.WaitForPopUp("id=popup_container", "30000");
  </code></pre>
  
  <p>But that doesn't work. Any help?</p>