Interface Requirement Analysis Method-user-centered UCD

1. Introduction

The software interface is a media between people and computers. The user exchanges information with the computer through the software interface. Therefore, the quality of the software interface is directly related to whether the performance of the application system can be fully utilized.
Users can work accurately, efficiently, easily, and happily. Therefore, software friendliness and ease of use are critical to the software system. At present, software developers in China pay great attention to software development technologies and their services during the design process.
Function, while ignoring the user's requirements for the software interface, affecting the ease of use and friendliness of the software. The research on the interface design is also focused on the interface design technology and design means. Software developers take experience as an example during design
Test basis, lack of understanding of actual user needs. The friendliness and ease of use of software are closely related to user features. Different users may have opposite comments on the same software interface. Therefore, we analyze user features and understand
User Requirements and operation habits are essential steps for developing the software interface and must be paid enough attention.

This article discusses an interface requirement analysis method, which is intended to explore how to define the interface requirements for all users of the system, so as to develop the interface accepted by users. The purpose of this method is to help the designer quickly identify the user's interface requirements, so that the user can fully participate in the interface requirement analysis, so as to reflect the user's ideas in the final interface requirement description, meet user requirements.

2. interface requirement analysis process

2.1 interface elements

Generally, the elements of a software interface include the main color, font color, font size, interface layout, interface interaction mode, interface function distribution, and interface input and output mode. Specifically, the user's work efficiency is significant.
The affected elements include: Input and Output Methods, InterAction methods, and function distribution. In a system using imperative interaction, command names and parameters are also the content of interface elements, it is also important to design commands and parameters.
The elements that affect the user's evaluation of system friendliness include: color, font size, and interface layout. This division is not absolute, and the software interface as a whole, any element does not meet user habits or requirements.
User requirements will reduce users' recognition of the software system, and even affect users' work efficiency, so that users end up using the system. The purpose of the design around the interface elements is to make the end users get the beauty
Sense, improve work efficiency, easy to operate and use the system.

At present, many studies have been conducted on the selection and layout design of interface elements, covering the discussion of ergonomics, cognitive psychology, aesthetics, and color theory.

2.2 User Role

The interface requirement analysis must be user-centered. Different from objective function requirement analysis, it is subjective. Although the interface designer can follow the principle of passing, the user's individual cultural background
Landscape, knowledge level, personal preferences, and so on are quite different, and their interface requirements are quite different. Different users have different requirements on the software interface, and the expressions of their requirements are also different. In addition, the user interface must be
It is usually not as easy to define, well-documented, and can be analyzed using specialized tools as business function requirements. Most users often do not have clear and global interface requirements, which are closely related to their own subjective factors.
The password is vague and changed. To investigate user interface requirements, you must first perform comprehensive processing on the requirements of different user groups based on the user's characteristics, and then analyze the interface requirements accordingly. So here
Introduce the concept model of user role.

User Roles refer to user types divided by a certain reference system. They are a set of multiple individual users that can represent certain user characteristics and facilitate uniform description. The purpose of the user survey is to investigate and analyze user features.
Feature, which summarizes a single user that cannot establish a model into a set, defines a user set as a role model, and gives different priority levels to understand and record the interface requirements. User requirement investigation and feature investigation are out-of-the-box
User roles are often defined at the same time. There are many survey methods, such as direct communication, data statistics, and table survey. The User Role Definition Principle is representative, which is related to system functions and has good interface requirements.
Analysis. A user role may include a large number of user individuals. Their requirements for the interface can be defined according to certain interface models. In a software system, user roles can be defined based on multiple systems
A single user can belong to different user roles under different reference systems, but a User Role requirement can represent a type of interface requirement. For example, the cashier divides a user according to the user's position.
Roles: system users in the Cashier's role can be divided into skilled users and unfamiliar users.

User role definition is an application of ergonomics theory in software development. The determination of user roles can be based on the user information and industry experience provided by the system's demand side, such as aesthetic concepts, user computer level, and user work content, then, modify and expand during the demand investigation.

The reason for defining a user role is that different user roles have different requirements and objectives in the demand analysis process, and have different focuses and even conflict with each other. In a large system
Users can only be a single user, and their needs are strange. Only when the user role is clearly defined can the requirement analysis personnel clarify the context in the complicated and unclear user requirements.
At the same priority level, the system balances conflicts among numerous user needs and abstracts a complete GUI model.

2.3 demand changes

We know that users can only put forward basic requirements on the interface, and the requirements are not necessarily scientific. Therefore, how to induce users to clarify their needs as soon as possible during project implementation, it is a problem for any requirement analysts.

The user's understanding of the target system and the change process of requirements are shown in:

The user puts forward his/her own requirements to the analysis and development personnel based on the ideal system he/she imagined. After the developer achieves the goal, the developer submits it to the user. After the system is implemented and run, the user will share the actual target system with his/her imagination.
In addition, the use of the target system will stimulate the user to correct the ideal system, and then propose new requirements. The software interface review factors are closely related to the user's psychological status and understanding.
System, so the user can only know whether the interface elements such as color and font meet their own requirements after using the software interface, in this way, more explicit requirements are put forward.

2.4 UI prototype

In the early stage of software development, users' interface requirements were vague, and they did not even have their own ideal models. Therefore, users' requirements were difficult to quantify and the results were easily ignored by demand analysts. Therefore, applying the quick prototyping method to design the user interface after the user role definition is complete can help users improve their ideal model as soon as possible.

The User Interface prototype can shorten the period of the user interface requirement survey and meet the user's requirements as much as possible. The quick prototyping method is a process that quickly generates a prototype of the software system based on the needs of the software system,
The main advantage is that you can obtain more complete and accurate requirements and designs as soon as possible. Using the interface prototype, users can perceive the interface style and operation method of the system in the future, and quickly make a judgment: whether the system is
Meet your sensory expectations, meet your operational habits, and meet your work needs. Demand analysts can use the interface prototype to induce users to correct their ideal systems and propose new interface requirements.
.

Therefore, the interface requirement analysis step can be: Determine the interface elements involved, analyze user features and define user roles, design the interface prototype based on user role interface requirements, and continuously improve and improve.

3. Requirement Analysis Results

3.1 user-oriented analysis results

The priority level of user roles is an important reference for Comprehensive processing of different user requirements. The requirements of different user roles on the interface elements are reflected in the interface element attributes, and the interface elements constitute the user interface. Interface
The final interface style varies with the attributes of elements. Different user roles in the same system may conflict with the requirements of the interface prototype. The requirement analysis depends on the user role priority.
Modify the interface prototype.

Different user roles have different implementation methods in the target system. Whether or not user requirements are reflected in the target system depends on the costs and benefits of implementing user requirements. Not all user interface requirements are reflected in the system interface. The interface is closely related to users. In specific circumstances, users can be trained to meet system requirements.

A friendly target system should be close to or even consistent with the user's ideal model. Therefore, the demand analysis should ultimately fully clarify the user's potential needs and implement the user's needs in the target system. In the demand analysis process, the user is always facing a visual and visualized actual running interface. Therefore, the result of the interface requirement is the target system interface that meets your own requirements.

3.2 designed for designers

Because the target system can be obtained directly by improving the prototype after the rapid prototyping method is applied, instead of starting from scratch, it can be analyzed together with the table method to form an accurate requirement specification. Table Method
The software interface components are divided into the minimum units of different categories and described. Different design schemes are developed based on the divided element units to list detailed tables, users can make their own
Select. See the following table:

Font and size
Title text
John
Bold

Text in the input box
5th

Menu text
5th

Command text
John

Help text
5th
Imitation Song

The table design principle is to use the interface elements as the basic content, and separate them reasonably based on user roles and system functions to fully and accurately describe the interface style. The content can be fixed into three parts: graphic design,
Interaction Mode definition and function model definition. Graphic design includes visual design and auditory design. It is usually an interface element that users can directly feel, allowing users to obtain psychological comfort and pleasure. Interaction Mode
It refers to the way in which computer systems and software systems communicate with users, including the use of the mouse and keyboard, whether there is a command mode, whether there is a voice output, information display mode, and so on. The function model definition is based on
A series of tasks to be completed by user roles. The corresponding system functions are built into a specific model according to a certain priority. The interface layout is organized according to this model to facilitate the user to complete a series of work. Actual
Most of the menus and navigation functions are related to the work series of user roles.

Using tables to form documents, the aim is to facilitate communication and build a bridge between designers and users.

4 Conclusion

The results of the interface requirement analysis should be clear, accurate, compliant with user habits, meeting the human-machine engineering requirements of the interface design scheme, can form a clear development documentation. This document describes how to convert fuzzy user requirements into clear and accurate requirement definition documents. This method can be used as a basic idea for Demand Analysis to expand, develop, and flexibly apply in actual projects.

Currently, this method has been applied in multiple projects, which is meaningful in improving the friendliness of software systems and reducing system implementation costs.