Interface Design Phases

Thebestindonesia.com – Dialog design is carried out in a top-down manner, meaning sequentially from a high-level system to a low-level one. The interface design process can be done stepwise refinement as follows:

1. Selection of Dialogue Variety

The choice of dialogue styles is influenced by the characteristics of the user population (first, intermediate or advanced users), the type of dialogs required, and the technological constraints to implement these dialogues.

2. Dialog Structure Design

At this stage, perform task analysis and determine the user model of the task to form an appropriate dialog structure.

3. Designing the message format

The display layout and detailed textual information should receive more attention at this stage. In addition, input data requires the user to enter data into the computer.

4. Error handling design

The need for a program to handle errors is intended to avoid abnormal termination. Namely, program execution stops due to a mistake.

Other forms of error handling include:

• Data entry validation. For example, if the user has to enter a positive number while entering negative or zero data, there must be a mechanism to repeat the data entry.
• User protection. The example program warns when the user accidentally acts, for example, by deleting a file.
• Error recovery. An example of the occurrence of a mechanism to undo a newly performed action.The appearance of the error message is precise and corresponds to the error that occurred at that time.
• An example of the appearance of an error message is when we give the wrong instructions.

5. Data structure design

Data structure design objective: to provide and support the required functionality of the interface components.

Read also : Ergonomic Aspects of Human and Computer Interaction

Things that the interface designer must consider:

Text-based display design

Application programs that base themselves on the ASCII character set.

Factors that influence this design:

• Serving order. The order of presentation must be adjusted to the user model that has been compiled. This is so that the user does not feel cheated or there is an agreement between the user and the designer.
• Leisure. This is intended so that specific texts can be placed in the correct position in the hope that they can immediately focus the user’s attention.
• Grouping. Interrelated data should be grouped to facilitate the overall display screen structuring.
• Relevance. Displays messages relevant to the topic currently displayed on the screen.
• Consistency. The designer should consistently use the available display space so that it is easy to study various types of information.
• Simplicity. Simplicity here refers to the easiest way to present information levels that users can quickly understand.

Graphic-based display design

Application program based on the image display.

Factors that influence this design. Based on the criteria that are owned in designing a graphical interface, several factors need to be considered when designing a graphical interface, each of which will be explained as follows:

• Illusion of objects that can be manipulated. Designing an effective graphical interface must involve three components. First, use a collection of things that are tailored to the application to be made. If those objects don’t exist yet, we can develop them ourselves. Second, the display of graphic things must be done with complete confidence that it will be easily understood by the user, third, use a consistent mechanism to manipulate the objects that will appear on the screen.
• Visual order and user focus. The graphical interface can attract the user’s attention, among others, by making objects blink, using specific colors for particular things, and presenting an animation that will attract the user’s attention more. This is intended, so the user becomes familiar with the display despite using a different system.
• Structural internals. In graphical interfaces, especially in objects that can be manipulated, the designer must also provide an internal structure (reveal structure), different from that used in textual documents, to tell the user how far he can change and manipulate the object. This mechanism and hidden elements, such as object alignment, are fundamental in designing graphical interfaces. Such a mechanism is dynamic (can be manipulated).
• Consistent and appropriate graphical vocabulary in the form of symbols or icons from one application to another should be consistent and proper. This is intended so that users using an application do not experience confusion. For example, the example of the (Save) button in every MS-Word application is the same as in the Excel application.
• Compatibility with the media. The characteristics of the display screen will significantly influence the beauty of the “face” of the interface that will be displayed. With the increasing sophistication of display screen technology at this time, the creativity of display designers is highly demanded to meet user demands for aspects of comfort and interface friendliness.

Read also : Interaction Devices

3. There is a Response Time

The time an application program provides in conveying messages to users when interacting with a computer.

Factors affecting response time:

• The desired variety of interactions.
• User fluency in running the application program.
• Different response times may affect user concentration.

4. There is error handling

Definition of a facility or method for handling errors when a user interacts with a computer.

There are two types of errors:

• Compile time error. The compiler will directly detect errors during program implementation, namely syntax errors. This error occurs while the program is compiling.
• Run time error or fatal error. Logic error while the program is being executed, resulting in an abnormal termination of program execution. The cause of the error can be from the user and the execution process.

In dealing with an error, the designer should make an error trap. An error message symbol is an example of using Visual Basic when using the On Error GoTo command. This error trap is usually structured with an IF then…Else structure that will match the error that occurs with the condition instructed.