A Novel Tool for Automatic GUI Layout Testing

As mobile apps are expected to run in many different screen sizes, the need to validate the correct positioning and rendering of graphical user interface (GUI) elements in such screens is increasing. In this paper, we first focus on identifying typical layout errors in modern GUIs and categorising them. Then, we implement a tool called Layout Bug Hunter (LBH) to automatically identify if a GUI layout is rendered correctly in different screen sizes. The tool is evaluated on mobile apps and is compared to state-of-the-art layout-testing tools. Results show that LBH can identify all the typical layout errors we categorise, and LBH is more accurate than a layout-testing tool based on image diffing algorithms. In addition, LBH does not require writing layout test scripts manually. LBH is currently implemented on only one mobile app development platform, but it is designed to be portable and extensible. With only limited effort, LBH can be extended to other mobile and web development platforms for layout testing.