CHAPTER12

advertisement
Input Design and Prototyping
Introduction

The chapter will address the following questions:







What is the appropriate format and media for a computer input?
What is the difference between data capture, data entry, and data
input?
Can you identify and describe several automatic data collection
technologies?
How do you apply human factors to the design of computer inputs?
How do you design internal controls for computer inputs?
How do you design a good source document for capturing
transaction data?
How do you select proper screen-based controls for input attributes
that are to appear on a GUI input screen?
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
1
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Data Capture, Data Entry, and Data Input
To input business data into a computer, the analyst may have to
design source documents, input screens, and methods and
procedures for getting the data into the computer.
 Data accompanies business events called transactions.
 Systems analysts must determine when and how to capture the
data.
 Data capture is the identification of new data to be input.
 It's always best to capture the data as soon as possible after it is
originated.
 Traditionally, special paper forms called source documents were
used to capture the data.
 A source document is a paper form used to record data that
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed will eventually be input to a computer.

by J. L. Whitten & L. D. Bentley
2
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Data Capture, Data Entry, and Data Input


Traditionally, special paper forms called source documents were
used to capture the data.
 A source document is a paper form used to record data that
will eventually be input to a computer.
With advances in video display technology, screen display forms
are able to duplicate the appearance of almost any paper based
form.
 Screen display forms and source documents must be designed
to be easy for the system user to complete and should facilitate
rapid data entry.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
• Data entry is the process of translating the source document into a
machine-readable format. That format may be a magnetic disk, an
optical-mark form, a magnetic tape, or a floppy diskette, to name a
few.
Copyright Irwin/McGraw-Hill 1998
3
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Data Capture, Data Entry, and Data Input

Data input is performed after data entry.
 Data input is the actual entry of data in a machine-readable
format into the computer.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
4
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Modern Input Methods: Batch versus On-Line Inputs

Input methods can be broadly classified as either batch or on-line.
 Batch input is the oldest and most traditional input method.
Source documents or forms are collected and then periodically
forwarded to data entry operators, who key the data using a
data entry device that translates the data into a machinereadable format.
 The most common medium for batch input data are Key-todisk (KTD) and key-to-tape (KTT) workstations that
transcribe data to magnetic disks and magnetic tape,
respectively.
• The data can be corrected, because it is initially placed into a
buffer.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
5
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Modern Input Methods: Batch versus On-Line Inputs

Today, most, but not all, systems have been converted or are being
converted to on-line methods.
 On-line input is the capture of data at its point of origin in the
business and the direct inputting of that data to the computer,
preferably as soon as possible after the data originates.
 The on-line system includes a monitor screen and keyboard that
are directly connected to a computer system.
 Most new applications being developed today consists of
screens having a “graphical” looking appearance called a
graphical user interface (GUI).
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
6
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Modern Input Methods: Batch versus On-Line Inputs

Today, most, but not all, systems have been converted or are being
converted to on-line methods.
 Remote batch offers on-line advantages for data that is best
processed in batches. The data is input on-line with on-line
editing. Microcomputers or minicomputer systems can be used
to handle this on-line input and editing. The data is not
immediately processed. Instead, it is batched, usually to some
type of magnetic media. At an appropriate time, the data is
uploaded to the main computer, merged, and subsequently
processed as a batch. Remote batch is also called deferred
batch or deferred processing.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
7
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology


Using today's technology, most if not all human intervention
associated with the input methods previously discussed can be
eliminated.
 By eliminating human intervention, the time-delay and errors
associated with human interaction can be decreased.
Biometric:
 Biometric ADC systems consist of sensors that capture an
individuals characteristic or trait, digitizes the image pattern,
and then compares the image to stored patterns for
identification.
 Biometric ADC are popular because they offer the most
accurate and reliable means for identification.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
8
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology

Electromagnetic:
 Electromagnetic ADC technology is based on the use of radio
frequency to identify physical objects.
• This technology involves attaching a tag and antenna to the
physical object that is to be tracked.
• The tag contains memory that used to identify the object that is
being tracked.
• The tag can be read by a reader whenever the object resides within
the electromagnetic field generated by the reader.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
9
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology

Magnetic:
 Magnetic ADC technology involves using magnetic stripe
cards, but also may include the use of magnetic ink character
recognition (MICR).
 MICR is most widely used in the banking industry.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
10
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology

Optical:
 Bar coding is an example of optical technology.
• Sophisticated laser readers read the bar code and send the data
represented by that code directly to the computer for processing.

The optical-mark form is another example of optical
technology.
• The source document becomes the input medium.
• The source document is directly read by an optical-mark reader
(OMR) or optical-character reader (OCR).
• The computer records the data to magnetic tape, which is then
input to the computer.
• OCR and OMR input are generally suitable only for high-volume
input activities.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
11
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology

Smart Cards:
 Smart card technology has the ability to store a massive amount
of information.
 Smart cards are similar, albeit slightly thicker, than credit cards.
• They also differ in that they contain a microprocessor, memory
circuits, and a battery.
• Smart cards are used on a daily basis by over 60% of the French
population.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
12
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Trends in Automatic Data Collection Technology

Touch:
 Touched-based ADC systems include touch screens, buttons,
and pen-based computing technology.
 Touch screen technology has been very popular in restaurant or
point-of-sale business applications.
 Pen-based computing is popular for applications that require
handwriting recognition.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
13
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

System User Issues for Input Design


Inputs should be as simple as possible and designed to reduce the
possibility of incorrect data being entered.
The following general principles should be followed for input
design:
 Capture only variable data.
 Do not capture data that can be calculated or stored in
computer programs.
 Use codes for appropriate attributes.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
14
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

System User Issues for Input Design


If source documents are used to capture data they should be easy
for system users to complete and subsequently entered into the
system.
The following suggestions may help:
 Include instructions for completing the form.
 Minimize the amount of handwriting.
 Data to be entered (keyed) should be sequenced so it can be
read like this book, top to bottom and left to right .
 Ideally, portions of the form that are not to be input are placed
in or about the lower right portion of the source document.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
15
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Good
xxxxx
(a)
xxxxxxxxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
(b)
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
xx-xx-xx
xxxxxxxxxx
xxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xx
xx
xx
xx
xx
xx
x.xx
x.xx
x.xx
x.xx
x.xx
x.xx
xxx.xx
xxx.xx
xxx.xx
xxx.xx
xxx.xx
xxx.xx
xxxxx
xxxxx
xxxxxxxxxx
xxxxxxxxxx
xxxxx
xxxxxxxxxx
xx.xxx
xx.xxx
xx-xxx-xxx
16
next line
next line
next line
next line
next line
stop
Bad
stop
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Internal Controls for Inputs



Internal controls are a requirement in all computer-based systems.
Input controls ensure that the data input to the computer is
accurate and that the system is protected against accidental and
intentional errors and abuse, including fraud.
The following internal control guidelines are offered for inputs:
 The number of inputs should be monitored.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
17
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Internal Controls for Inputs

The following internal control guidelines are offered for inputs:
(continued)
 Care must also be taken to ensure that the data is valid.
• The following techniques are widely used to validate data:
– Completeness checks determine whether all required fields on
the input have actually been entered.
– Limit and range checks determine whether the input data for
each field falls within the legitimate set or range of values
defined for that field.
– Combination checks determine whether a known relationship
between two fields is valid.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
18
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Methods & Issues for Data Capture & Input

Internal Controls for Inputs

The following internal control guidelines are offered for inputs:
(continued)
 Care must also be taken to ensure that the data is valid.
• The following techniques are widely used to validate data:
(continued)
– Self-checking digits determine data entry errors on primary
keys. (see following figure)
– Picture checks compare data entered against the known
COBOL picture or other language format defined for that data.

Data validation requires that special edit programs be written to
perform checks.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
19
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
MODULUS 11
The following procedure is used to assign a check digit to a key field:
STEP 1: Determine the size of the key field in digits.
2 4 1 3 5 = 5 digits
STEP 2: Number each digit location from right or left beginning with the number “2.”
24135
65432
STEP 3: Multiply each digit in the key field by its assigned location number.
2 X 6 = 12
4 X 5 = 20
1X4=4
3X3=9
5 X 2 = 10
STEP 4: Sum the products from step 3.
12 + 20 + 4 + 9 + 10 = 55
STEP 5: Divide the sum from step 4 by 11.
55/11 = 5 Remainder 0
STEP 6: If the remainder is less than 10, append the remainder digit to the key field. If
the remainder is equal to 10, append the character “X” to the key field.
241350
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
20
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Introduction

Most new applications being developed today include a GUI.
 This approach is influenced by a new trend in programming,
called repository-driven programming.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
21
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
22
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
4
1
5
2
6
7
3
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
23
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Text Box




A text box consists of a rectangular shaped box that is usually
accompanied by a caption.
A text box requires the user to type the data inside the box.
A text box can allow for single or multiple lines of data characters
to entered.
When a text box contains multiple lines of data, scrolling features
are also normally included.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
24
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Text Box


When to Use Text Boxes For Input:
 A text box is most appropriately used in those situations where
the input data values are unlimited in scope and the analyst is
unable to provide the user with a meaningful list of values from
which they can select.
Suggested Guidelines for Using Text Boxes:
 A text box should be accompanied by a descriptive caption.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
• Avoid using abbreviations for captions.
• Only the first character of the caption’s text should be capitalized.
• The caption should be located to left of the actual text box or leftaligned immediately above the text box.
• The caption should be followed by a colon to help the user visually
distinguish the caption from the box.
25
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Text Box

Suggested Guidelines for Using Text Boxes: (continued)
 The size of the text box should be large enough for all
characters of fixed-length input data to be entered and viewed
by the user.
• When the length of the data to be input is variable in length and
could become quite long, the text box’s scrolling and wordwrapping features should be applied.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
26
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Radio Button

A Radio button consists of a small circle and an associated textual
description that corresponds to the value choice.
 The circle is located to the left of the textual description of the
value choice.
 Radio buttons normally appear in groups - a radio button per
value choice.
 When a user selects the appropriate choice from the value set,
the circle corresponding to that choice is partially filled to
indicated that it has been selected.
 When a choice is selected, any default or previously selected
choice’s circle is deselected.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
27
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Radio Button


When to Use Radio Buttons For Input:
 When a user is expected to input data that has a limited
predefined set of mutually exclusive values.
Suggested Guidelines for Using Radio Buttons:
 Radio buttons should present the alternatives vertically aligned
and left-justified to aid the user in browsing.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
• The choices can be presented where they are aligned horizontally,
but adequate spacing should be used to help visually distinguish
the choices.
• The group of choices should be visually grouped to set them off
from other input controls appearing on the screen.
• The grouping should also contain an appropriate meaningful
caption.
28
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Radio Button

Suggested Guidelines for Using Radio Buttons: (continued)
 The sequencing of the choices should also be given
consideration.
 It is not recommended that radio button(s) be used to select the
value for an input data whose value is simply a Yes/No (or
On/off state).
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
29
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Check Box





A check box also consists of two parts.
 A square box followed by a textual description of the input field
for which the user is to provide the Yes/No value.
Check boxes provide the user the flexibility of selecting the value
via the keyboard or mouse.
An input data field whose value is “Yes” is represented by square
that is filled with an “x”.
The absence of an “x” means the input field’s value is “No”.
The user simply toggles the input fields value from one value/state
to the other as desired.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
30
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Check Box


When to Use Check boxes For Input:
 When a user needs to input a data field whose value set consists
of a simple “Yes” or “No” value.
Suggested Guidelines for Using Check boxes :
 Make sure that the textual description is meaningful to the user.
 Arrange the group of check box controls where they are aligned
vertically and left-justified.
• If necessary, align horizontally and be sure to leave adequate space
to visually separate the controls off from one another.

Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
Appropriately sequence the input fields according to their
textual description.
31
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

List Box





A list box is a control that requires the user select a data item’s
value from a list of possible choices.
The list box is rectangular shaped and contains one or more rows
of possible data values.
The values may appear as either a textual description or graphical
representation.
List boxes having a large number of possible values may consist of
scroll bars to navigate through the row of choices.
A list box’s row may contain more than one column.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
32
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

List Box


When to Use List Boxes For Input:
 A list box’s scrolling capabilities make it appropriate for use in
those cases where there is limited screen space available and
the input data item has a large number of predefined, mutually
exclusive set of values from which to choose.
Suggested Guidelines for Using List Boxes:
 A list box should be accompanied by a descriptive caption.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
• Avoid using abbreviations for captions and capitalize only the first
character of the caption’s text.
• The caption should be followed by a colon to help the user visually
distinguish the caption from the box.
• The caption should appear left-justified immediately above the
actual list box.
33
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

List Box

Suggested Guidelines for Using List Boxes: (continued)
 It is recommended that a list box contain a highlighted default
value.
 The width of the list box should be large enough for most
characters of fixed-length input data to be entered and viewed
by the user.
 The length of the box should allow for at least 3 choices and be
limited in size to containing roughly 7 choices.
 Scrolling features should be used to suggest additional choices
are available to the user.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
34
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

List Box

Suggested Guidelines for Using List Boxes: (continued)
 If graphical representations are used for value choices, make
sure they are meaningful and truly representative of the choice.
 If textual descriptions are used, use mixed-case letters and
ensure that the descriptions are meaningful.
 The list of choices should be left-justified to aid in browsing.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
35
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Drop-Down List


A drop-down list is another control that requires the user to select a
data item’s value from a list of possible choices.
A drop-down list control consists of a rectangular shaped selection
field with a small button connected to its side.
 The small button contains the image of a downward pointing
arrow and bar.
• This button is intended to suggest to the user the existence of a
hidden list of possible values for a data item.
• When requested, the hidden list appears to “drop or pull down”
beneath the selection field to reveal itself to the user.

Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
When the user selects a value from the list of choices, the
selected value is displayed in the selection field and the list of
choices once again becomes hidden from the user.
36
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Drop-Down List


When to Use Drop-Down Lists For Input:
 A drop-down list should be used in those cases where the data
item has a large number of predefined values and screen space
availability prohibits the use of a list box to provide the user
with a list box.
 Once disadvantage of a drop-down list is that it requires extra
steps by the user, in comparison to the previously mentioned
controls.
Suggested Guidelines for Drop-Down Lists:
 The caption for a drop-down list is generally either left-aligned
immediately above of the selection field portion of the control
or located to the left of the control.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
37
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Combination (Combo) Box


A “combo box” combines the capabilities of a text box and list
box.
 A combo box allowsthe entering of a data item’s value (as with
a text box) or by selecting its value from list (as with a list box).
The associated small button is not directly connected to the
rectangular entry field.
 Once the small button is selected, a hidden list is revealed.
 The revealed list appears slightly indented beneath the
rectangular entry field.
 When the user selects a value from the list of choices, the
selected value is displayed in the entry field and the list of
choices once again becomes hidden from the user.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
38
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Combination (Combo) Box


When to Use Combo Boxes For Input:
 A combo box is most appropriately used in those cases where
limited screen space is available and it is desirable to provide
the user with the option of selecting a value from a list or
typing a value that may or may not appear as an option in the
list.
Suggested Guidelines for Combo Boxes:
 The same guidelines for using drop-down lists directly apply to
combo boxes.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
39
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Spin (Spinner) Box

A spin box is a screen based control that consists of a single-line
text box followed immediately by two small buttons.
 The two buttons are vertically aligned.
 Top button has an arrow pointing upward and the bottom button
has an arrow pointing down.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
40
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Spin (Spinner) Box

This control allows the user to enter data directly into the
associated text box or to select a value by using the mouse to scroll
(or “spin”) through a list of values using the buttons.
 The buttons have a unit of measure associated with them.
 When the user clicks on one of the arrow buttons, a value will
appear in the text box.
 The value in the text box is manipulated by clicking on the
arrow buttons.
• The upward pointing button will increase the value in the text box
by a unit of measure; whereas the downward pointing button will
decrease the value in the text box by the same unit of measure.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
41
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Spin (Spinner) Box

When to Use Spin Boxes For Input:
 A spin box is most appropriately used to allow the user to make
an input selection by using the buttons to navigate through a
small set of meaningful choices or by directly keying the data
value into the textbox.
 The data values for a spin box should be capable of being
sequenced in a predictable manner.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
42
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
GUI Controls for Input Design

Spin (Spinner) Box

Suggested Guidelines for Spin Boxes:
 Spin boxes should contain a label or caption that clearly
identifies the input data item.
• This label should be located to the left of the text box or leftaligned immediately above the text box portion of the control.

Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
Spin boxes should always contain a default value in the text
box portion of the control.
43
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 1: Review Input Requirements


The design unit DFDs depict inputs to be designed.
 These inputs can are represented as data flows that connect
external entities to processes.
Review the required attributes of data inputs.
 For each attribute, the designer must identify an appropriate
caption or label they will use to clearly identify to the user the
attribute appearing on the screen.
 The size and edit mask (or format) of the attribute must be predetermined.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
44
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 2: Select the GUI Controls

To choose the correct control for our attributes, you must examine
the possible values for each attribute.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
45
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 3: Prototype the Input Screen




This step involves developing prototype screens for the user to
review and test.
 Their feedback may result in the need to return to steps 2 and 3
to add new attributes and address their characteristics.
When prototyping input screens, it is important to actually let the
user exercise or test the screens.
 Part of that experience should involve demonstration on how
the user may obtain appropriate help or instructions.
Prototypes should demonstrate to the user how security will be
handled.
Prototypes should demonstrated how error handling with be
accomplished.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
46
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
3
1
2
5
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
4
47
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
(b)
(a)
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
48
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
(a)
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
(b)
49
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
50
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 4: If Necessary, Design or Prototype the Source
Document



If a source document will be used to capture data, we must also
design that document.
The source document is for the system user.
 In its simplest form, the prototype may be a simple sketch or an
industrial artist's rendition.
A well-designed source document will be divided into zones.
 Some zones are used for identification; these include company
name, form name, official form number, date of last revision
(an important attribute that is often omitted), and logos.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
51
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 4: If Necessary, Design or Prototype the Source
Document

A well-designed source document will be divided into zones.
(continued)
 Other zones contain data that identifies a specific occurrence of
the form, such as form sequence number (possibly preprinted)
and date.
 The largest portion of the document is used to record
transaction data.
• Data that occurs once and data that repeats should be logically
separated.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
52
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
How to Prototype & Design Computer Inputs

Step 4: If Necessary, Design or Prototype the Source
Document

A well-designed source document will be divided into zones.
(continued)
 Totals should be relegated to the lower portion of the form
because they are usually calculated and, therefore, not input.
 Many forms include an authorization zone for signatures.
 Instructions should be placed in a convenient location,
preferably not on the back of the form.
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
53
Copyright Irwin/McGraw-Hill 1998
Input Design and Prototyping
Summary




Introduction
Methods & Issues for Data Capture & Input
GUI Controls for Input Design
How to Prototype & Design Computer Inputs
Prepared by Kevin C. Dittman for
Systems Analysis & Design Methods 4ed
by J. L. Whitten & L. D. Bentley
54
Copyright Irwin/McGraw-Hill 1998
Download