From one point of view, user interface – is the part of a software system. Consequently, testers write functional and low-level requirements for the user interface, based on which the test requirements and test plans are compiled.

Thus, as a rule, requirements define the system reaction for each user input (keyboard, mouse or another input device) and the kind of system information messages displayed on the screen, printer or another output device. When testers execute independent verification and validation services for such requirements, they mean a functional verification of the user interface testing services completeness.

From other point of view, user interface – is the “face” of the system and the effectiveness of user work depends on its relevance. Factors that influence the work effectiveness are weakly amenable to formalization in the form of specific requirements for individual items. However, the following shall be considered as general recommendations and principles of building the user interface of a software system.

Functional Testing for User Interface

Software testers may perform functional testing services for user interface, which consists of six phases:

• UI requirements analysis;
• development of test requirements and plans for user interface testing;
• test case execution;
• collecting information about tests performance;
• defining the completeness of user interface coverage towards requirements;
• compiling the bug reports in case of mismatch between the system behavior and requirements.

All these phases are similar to testing of any other software system component. The differences can be only in the terms interpretation in user interface testing and in peculiarities of automated collection of information on each phase.