Greetings, Testers. As you're no doubt aware, Web applications these days often have controls and elements that are populated without a full page refresh - using Ajax for example - and this means that automated tests need a little additional help.
Traditionally, automated tests perform their actions and validations based on feedback from the browser, given when a page has finished loading. If the contents of the page are changing without a page load, then the browser doesn't report that back to Test Studio. There are plenty of cases where a person would know to wait for something to happen, or wouldn't even think about it.
I've put together a video on this: Explicit Waits with AJAX: an Example using Drop-down Lists. In the video, I use use a page that simulates slow refresh from a server. Each of the drop-down lists takes several seconds to populate. If an automated test were just to try to make selections, it would fail. We need to have the test instead wait (not sleep) for the elements to be ready.
Take a look and let us know here in the comments section, in our Test Studio forums, or over on Twitter what sort of situations are causing you challenges.
Peace,
Steven