software engineering - 09

8/7/2019 Software Engineering - 09

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Software Engineering

User Interface Design

Presented By

Aamir Abbas


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Topics


User Interface


Models

Process

Task Analysis and Modeling Interface Design Activities

Implementation Tools

Design Evaluation


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User Interface

Communication medium between human

and computer.

UI molds users perception of the software.

User will NOT like a software, regardless of

its computational power, if it is difficult touse, or if it frustrates you to accomplishyour goals.


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Process of UI design generally includes:

Create different models of system functions(as perceived from the outside)

Delineate human- and computer-oriented tasksrequired to achieve system functions.

Consider design issues for all interfaces.Use tools to prototype and implement design

model.

Evaluate the result for quality.


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User Interface Design Models

Design Model

Incorporates data, architectural, interface andprocedural representations of the software.

User Model

Establishes the profile of end-users.

Categorizes the users (categories may vary)

Novice users

Knowledgeable, intermittent users

Knowledgeable, frequent users


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User Interface Design Models

System Perception

The image end-users carry in their heads.

The accuracy depends on users profile.

System Image

Combines CBS UI interface and supportinginformation (books, manuals, video-tape etc).

Interface designer reconciles these models andderive a consistent representation of the interface.


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User Interface Design Process

Iterative process, can be represented like a

spiral model. Four distinct framework activities

User, task and environment analysis andmodeling

Interface design

Interface construction

Interface validation


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Task Analysis and Modeling

Identify human activities and map into

similar set of tasks in user interface context Human engineer must define and classify

tasks.

Design model of interface shouldaccommodate tasks consistent with usermodel and system perception.


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Interface Design Activities

Define interface objects and actions

applied to them, categorized by type. Screen layout is performed, which is an

interactive process.

User-interactive / Graphical design

Definition of descriptive screen text

Specification of windows and titling

Interface design is elaborated and is an

iterative activity.


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Interface Design Implementation

Interface design implementation is usually

carried out using language-based orgraphical interface design tools.

Interface design is sometimes implementedas an operational prototype.

The proposed design or prototype isexamined by users and is modified basedon their comments.


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Interface Design Evaluation

Interface design is evaluated to determine

whether it meets the user needs. Evaluation is generally performed by the

users, which range from an informal test-drive to a formal questionnaire or ratings.

Evaluation is an iterative process, andcontinues until the user is satisfied.


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Interface Design Evaluation

software engineering - 09

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