Reduce Visual Work |
Issue: We find that some developers
fail to recognize that their screens merit the text approach to reading
the rectangle. They design with the artistic approach. They think that
by making some area in the screen appear dominant, the user will automatically
look there and subsequently figure out the task flow. Crypto-designers
erroneously hope that highlighting, blinking, and textual emphasis like
bold or italics can override a poorly sequenced layout (see Figure
4). Here the "note" at the bottom of the screen really
serves as a warning. It's quite important. Although bold text may make
it stand out, most users still fail to read the note prior to entering
the forbidden Y value.
Solution: Sequence all your fields,
menu options, and other screen elements to match a left-right, top-down
task flow. If the task has no clear sequence, group items by subject or
function. Lay out your screen so that important items like warnings (as
in Figure 4) and critical guidance show up
first. In other words follow the logical task flow, with warnings preceding
the action.
Figure 4. The warning "note" fails
to capture the users attention even though the designer put it in bold.
When tempted to highlight or emphasize text to get user attention, you
probably lack the right layout sequence. Sequence guidance and other instructions
in the task flow to eliminate the need for emphasis.
Some corollary soul solutions to visual work in layout design:
- Avoid putting important items in the "status bar" typically
used at the bottom of the window. The status bar is spatially too far
removed from the other screen elements to attract the user's attention
for special cases. Important messages deserve special prominence such
as a dialog box or placement at the top of the window. These include
error and warning messages, system messages and informational messages.
However, you can display field definitions in the status bar without
compromising usability.
- Put field labels to the left of the field. Avoid placing the labels
above the field or below it because it contradicts the normal habit
of left-right reading.
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Reduce Memory Work |
Issue: Cryptolayout lapses can increase
memory demands. For example, the user may see a start date and an end
date side-by-side. Can you compare the days, months, and years easily?
See Figure 5. The eye cannot take both date
elements within the same glance. You must remember one and mentally compare.
Solution: When the user benefits from
comparing two dates, then position one date above the other. The user
can easily compare year, month, and day in a single glance, given their
spatial proximity.
Some corollary solutions to memory demands in layout design:
- Avoid covering fields with their associated error messages or detail
dialog boxes. Users won't remember what they did. To see the field,
position dialog boxes below and to the right of the field. However,
a single standard position for these dialog boxes won't work because
fields can be anywhere on the screen. Therefore, build in some "smarts"
to your application. Position the dialog according to field position
on the screen . Use this algorithm: First choice: below and to the right
of the field; second choice, to the right; third, below the field; fourth,
above and to the right; fifth, above the field; sixth, to the left of
the field.
- Avoid slavish crypto-placement of field labels to the left of the
field. (Although, normally we should place the label to the left of
the field.) Consider the user's task! For example, exceptions occur
when users read a paper form for data entry and the paper form has the
label above or below the line. Ideally, the screen should mimic the
form layout. This minimizes user memory requirements for mentally "translating"
between the form and the screen layout (see Figure
5).
Figure 5. How compare dates easily? Here a single glance fails to get both dates at once. You must work hard to
remember one date while reading the other. Solution:
place the latter date below the earlier one. Next: How to position labels?
Solution: Put labels on
the left - but remember to reduce crypto memory demands in special cases.
Match your screen layout to paper forms that may have labels below the
line. Then users won't need to remember how to translate field names and
sequences between paper and screen.
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