Creating an OOED Application
1)
2)
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5)
Plan the Application
Build the User Interface
Code the Application
Test and Debug the Application
Assemble the Documentation
1) Planning an OOED Application
A) Identify the tasks the application needs to
perform
B) Identify the objects to which those tasks
will be assigned
C) Identify the event(s) necessary to trigger
those objects to perform their assigned
task(s)
D) Draw a sketch of the user interface
A) Identifying the Application’s Tasks
• What information will the user need to
enter?
• What information will the application need
to calculate?
• What information will the application need
to display on screen or print on printer?
• How will the user end the application?
• Will previous information need to be
cleared?
B) Identifying the Objects
• Assign each task to an object in the user
interface
– Label - used to display information that the
user will not change.
– Text box - used to give the user an area to enter
data.
– Command button - used to perform an action
immediately after it is clicked by the user.
C) Identifying the Events
• Label - automatically display their contents;
no special event needs to occur.
• Text box - accept information automatically
from the user; no special event needs to
occur.
• Command button - needs a click event to
occur to carry out their assigned task
when they are clicked by the user.
D) Sketching the User Interface
• Organize the user interface to information
flows either vertically or horizontally,
with most important information in
upper-left corner of the screen.
• Command buttons should be centered along
the bottom or stacked in either the
upper-right or lower-right corners.
• Each control is labeled so the user knows its
purpose.
Principles of Good User Interface
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Control
User-friendly
Intuitiveness
Consistency
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Clarity
Feedback
Graphics
Input
2) Build the User Interface
• Use TOE chart and sketch created in the
planning step as guides when building
the interface.
• Involves placing the appropriate controls on
the form and setting the applicable
properties of those controls.
– Placing and sizing design elements
– Selecting appropriate font style and size
– Selecting appropriate colors
3) Code the Application
• Flowchart - provides a visual frame of
reference of the processing steps in a
program.
• Pseudocode - narrative descriptions of
processing steps to be performed in a
program.
• Internal Documentation - refers to
comments in the Code window.
• Syntax - rules when writing comments/code
3) Code the Application
• Flowchart - provides a visual frame of
reference of the processing steps in a
program.
• Pseudocode - narrative descriptions of
processing steps to be performed in a
program.
• Internal Documentation - refers to
comments in the Code window.
• Syntax - rules when writing comments/code
3) Code the Application
• Flowchart - provides a visual frame of
reference of the processing steps in a
program.
• Pseudocode - narrative descriptions of
processing steps to be performed in a
program.
• Internal Documentation - refers to
comments in the Code window.
• Syntax - rules when writing comments/code
4) Test & Debug the Application
• Testing
– Valid data
– Invalid data
• Debugging
– Syntax errors
– Run-time errors
– Logic errors
5) Documenting the Program
• Consists of written descriptions and
explanations of programs and materials.
• Serves as a reference guide.
• Includes TOE chart, user interface sketch,
flowcharts, and pseudocode.
• Application printout includes form image,
form as text, and code.
Desirable Program Qualities
• Programs should be:
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Easy to read and understand
Efficient
Reliable
Robust
Maintainable