CCP4i Task Window Style Guide
Liz Potterton
The Task in Context
Understand the context in which a program is used:
talk to program authors and expert users
look at scripts
Design the interface to do the whole 'task' rather than run an individual
program.
Ensure users will not need to do file format conversions on input or
output files.
Present the task and the options within the tasks in terms of what goal
is achieved.
(Existing task names like 'Run Refmac' do not do this!)
Sensible Defaults
For the most common usage of a task a user should only need to select files
(and MTZ columns) and provide non-default data.
If a task has several popular modes then these should be presented
as a menu (at the top of the window) and after the user has selected the
mode then all defaults should be appropriate for that mode. (This
may mean having two variables with different defaults for one input parameter.)
Rules for Customising the Task Window
When a user selects a particular mode or option the task window should
be customised for that option - nothing irrelevant to that option should
be visible.
A mode or option should only control the visibility of widgets that
are further down the task window.
A stricter rule is that a mode or option should only control the visibility
of widgets in the same folder except:
A mode/option in the Protocol folder can change anything in the window.
Only a mode/option in the Protocol folder should affect the visibility
of whole folders.
Overall Folder Layout
General scheme is: Protocol, Files, 'Frequently Used Options', folders
for specific aspects, 'Infrequently Used Options' (a ragbag).
The 'Frequently Used' options may relate to completely different aspects
of the task but they are the set of options that a novice user ought to
think about.
All other options should be grouped into folders for specific subject
areas with a clear folder title. Ideally these folders should be
closed.
A ragbag of 'Infrequently Used' options is occasionally necessary.
What Goes in the Protocol Folder?
There is no clearcut distinction between 'Protocol' and 'Frequently Used'.
The rules for customising the task window mean that any option which
changes the input/output files or visibility of whole folders should go
in the Protocol folder.
"Do I have to do something here?"
This is the most confusing thing about interfaces for a user.
Compulsory input should be indicated by the contrast gold colour.
(-oblig option to CreateLine).
The way some programs work is that they determine the required
mode of action based on the input MTZ columns - it is not acceptable to
carry over this approach to the GUI! The user should choose what they want
to do in the protocol folder and only the necessary column label selection
should be visible.
Layout of 'Complex' Data
For example the definitions of heavy atom in heavy atom refinement.
Ideally all of the information that a user might want to view and edit
at one time should be in one folder and not spread throughout the task
window.
Help Facilities
Do:-
Use the message option to give *extra* information about
an input. Also include the command file keywords(s), if appropriate,
as (KEYWORD) at the end of the message line.
Use the target option to provide a link to further
information.
Write GUI specific documentation which probably should be more novice-oriented
than program documentation. But, it should also have a section, for
the benefit of experts, explaining what a complex run script is doing -
particularly if it is running subsidiary, utility programs.
Fine Tuning
Expect to have to revise the GUI in the light of input from users.
Get prototype version of GUI tested by experts and users.
Task Window Names
Task window names should be the same as the task name on the menus (this
ought to be enforced automatically!).