This article focuses on the concept of a Pattern Supported Approach (PSA) for the design of User Interfaces. Up to this point most of the work on patterns for interfaces has focused on the screen design issues. PSA suggests a wider scope for the use of patterns by looking at the overall user oriented user interface design process. The primary challenges at hand here are to not only address patterns at the design phase but before design. That is, proposing patterns for system definition, task analysis and conceptual design. By this method, the patterns offer a way to capture and communicate knowledge from previous designs, such as the previously mentioned ones, and will act as tools to guide and support the usability engineering tasks.
This approach is not entirely new; many have practiced usability testing like this before. However, the major concern here is learning as much as possible about the current situation (task user analysis) and predicting what is needed for the future system. In addition, collected information before design is usually from interviews, questionnaires, old systems, etc. Using these sources means gathering quite a bit of information and analyzing it which can prove to require a lot of effort and tend to be cumbersome. Reuse of information and design definitely occur for similar projects, but this often adds havoc and could be affected by the individual?s ability and personal experiences.
To deal with this challenge, the pattern approach provides the added value of accumulated knowledge and design experience in a format that?s easy to understand. It should be equivalent to having a senior colleague on your team. Results that have addressed these challenges include a number of patterns that point to information that is generally valid about the UI domain and also designs that have proven good for similar projects. As mentioned earlier, the process before the design is so important that there are patterns that are specific to those areas. Overall there are domain specific patterns (Business Domain Patterns, Business Process Patterns & Task Patterns), which lead up to a suitable Conceptual Design Pattern.
The usability of a system emerges as a product of User, Task and Context of Use. The intent of the suggested patterns is to strengthen the analysis of these three components and communicate knowledge form previous designs. The design process starts with the system definition. During this stage the vision is captured and the goal is to collect background information and set the scope, constructing a common understanding. To facilitate this, Business Domain patterns are used. The pattern is reviewed and differences in the businesses are adjusted to suite the specific situation. A Task Pattern is then chosen based on the particular Business Pattern. There are many Task Patterns for each Business Pattern. This Task Pattern helps describe the main tasks and user groups that are involved in the system. The Task Pattern is optimized by utilizing user profile and task analysis activities. Similarities and discrepancies between this process is the basis for Conceptual Design patterns in which information and activities are arranged to support the ultimate goal of any user interface; to effectively support the user?s task.
This process tends to produce successful results in addressing the challenges of creating User Interfaces. The article suggests that it is inappropriate to change patterns or write new patterns during the design process. After all knowledge is gained the patterns can later be evaluated and updated based on the new situations that arose from that project. There are open questions that remain which require further research. A list of five questions follows below.