We have mentioned many times in this book that Motif attempts to enforce a
standard style in the look and feel of its applications through the
window manager and default widget actions. One of the goals of Motif is to
provide the user with a consistent and easy to use set of applications.
Therefore no application should deviate too far from the prescribed Motif norm.
In some instances it may be necessary for the programmer to break certain Motif
practices in order to achieve a desired form of user interaction. We illustrated
this point when we described input to the DrawingArea widget in
Motif's basic style is based on the (IBM) CUA guidelines . Motif provides many default actions for
widgets that adhere to standard GUI practices as layed down by these
guidelines. However, when creating widgets
the programmer still has some freedom in how the GUI is constructed. For
example, menus, menu bars, mouse actions and dialog can take on many different
forms. In order to maintain consistency across applications Motif provides a set
of guidelines that provide a framework for application development, widget
designers, user interface designers and window manager designers. These
guidelines are published in the Motif Style Guide . This Chapter summarises the important features in the Motif Style
Guide that are relevant to the application developer.
As we have just mentioned the Motif Style Guide is a
document that is aimed at four specific audiences: application
development, widget designers, user interface designers and window manager
designers. A such the guide is divided up into a number of sections. Not all
sections are especially relevant for each audience. Clearly the widget designers
and user interface designers will need to be familiar with a majority of the
guide, however, application designers need only be familiar with three major
aspects of the guide: User Interface Design Principles, Application
Design Principles and Internationalisation.
Throughout this text we have already addressed many issues related to the
Motif Style Guide. We now concentrate on important aspects of style related to
specific widgets and general user interaction.
The Motif Style Guide provides many guidelines on the usage of menus in
Motif. Menus are usually organised (Chapter 8) in a
of a MainWindow widget. Motif
style insists that:
- The MenuBar must be placed horizontally at the top
of edge of the application just below the title area of the MainWindow window
- The MenuBar must contain only CascadeButtons with PullDownMenus
connected to them . Other
classes of button inhibit menu browsing.
- Each menu in the MenuBar should have a single letter
mnemonic (Section ) attached for
easy keyboard selection and each mnemonic should be indicated by underlining.
Many applications have a general functionality, in which case the following
general MenuBar menus should be provided with the given mnemonics (in brackets):
- (Meta-F) -- This menu should contain
selections for performing file handling actions such as creating, opening,
saving, closing and printing. It should also contain actions for handling the
documents as a whole, such as quitting. The following items and mnemonics are
- (Meta-N) -- Create a new file.
- (Meta-O) -- Open a file. A
FileSelectionDialog usually appears to allow the user to choose a file.
- (Meta-S) -- Save the current file to its current
- Save As
- (Meta-A) -- Save the current file to
a different name
- (Meta-P ) -- Print the current file.
- (Meta-C ) -- Close the window. This option
must only be supplied in applications that have multiple independent
primary windows. The action must only close the current primary window and
associated child windows.
- (Meta-x) -- Quit the application.
- (Meta-S) -- This menu should contain
selections for objects currently selected by the application. Many items are
common with the File menu options but are specific to the selected item.
Options covered by the Edit menu (below) should not be included in
this menu. The Selected menu is not that commonly used.
- (Meta-E ) -- This menu should contain options for
performing actions on the current data of the application. This menu uses
Motif's keyboard accelerators for selection
of some items. Keyboard accelerators are much like mnemonics except that they
are arbitrary key combinations. The control (Ctrl), Shift and
Alt keys in combination with other keys are typically used and the
particular key assignment model may vary depending on local computer keyboard
configurations or host computer compatibility requirements. For example, Apple
Macintosh computers have a different cut, paste, copy and undo accelerator
model that adheres to standard Macintosh practice for these actions.
In order to set the keyboard
accelerator for an appropriate menu item the resources
XmNaccelerator (String) and
XmNacceleratorText (XmString) to set the key
combination and menu item label respectively. For example
the string used to set the XmNaccelerator resource for the Ctrl-/ key
with applicable keyboard accelerators or mnemonics denoted in brackets, include:
- (Alt-Backspace) -- Undo the last user operation.
- (Shift-Del) -- Remove the selected portion of data
and store it in the clipboard . The clipboard is a Motif
resource which provides a localised area of memory that allows easy transfer of
data within and between applications via cut and paste actions.
- (Ctrl-Ins) -- Copy the selected portion of data
and store it in the clipboard.
- (Shift-Ins) -- Copy the current contents of the
clipboard to the current location.
- (Meta-e) -- Remove the selected data
without copying it to the clipboard. The remaining data is not compressed to
the space left by this operation.
- (Meta-D) -- Remove the selected data
without copying it to the clipboard, moving following data to fill the space
left by this operation.
- Select All
- (Ctrl-/) -- Select all elements in current work area.
- Deselect All
Ctrl-\) -- Deselect selected items.
- (Meta-V) -- This menu should contain options
allowing the user to change the display of data. The exact makeup of this
menu will depend on the application but can include options to control the order
of the displayed data, the amount of data displayed or the appearance of the
data. For example, in the CDE desktop file manager you can list files by
icon or by text and files may be listed in alphabetical order or by date.
- (Meta-O) -- This menu should contain options
allowing the user to customise the application. Once more this menu is very
application dependent. One common example is providing facilities that allow
the user to change the colours used by the application.
- (Meta-H) -- This menu should contain items
that provide the user with facilities that guide and inform the user to
effectively use the application. DialogBox widgets are usually used to convey
the Help information. The Help menu must be placed on the far
right of the MenuBar (Chapter 8).
Motif Style prescribes two
acceptable models for the Help menu. One is based on providing help on
various components of the application such as how to use windows, function
mnemonic and accelerator keys. Tutorial information may also be specified. The
other model is similar to a user manual approach providing an overview, index and
In addition to prescribing the organisation and formatting of menus the style
guide also provides some general guidelines on menu design. Briefly these are:
Applications use Dialog widgets to interact with the user. They may simply
supply information to the user or may actually canvas for some input (
e.g. file selection). Applications should only display Dialog boxes when they
are required. Motif provides specific Dialog widgets for specific occasions.
Examples include ErrorDialog, WarningDialog, CommandDialog, PromptDialog and
FileSelectionDialog widgets. The specific usage of Dialog widgets has already
been addressed in Chapter 9
- Keep menu structures simple.
- Group similar menu elements together.
- List menu items by frequency of use.
- List menu items by order use (which may be more important than frequency
- Separate destructive actions from frequently chosen items to avoid
- Provide keyboard mnemonics and accelerators for frequently chosen items.
- Provide tear-off menus for in frequently used menus (Chapter 8).
Motif provides a variety of guidelines for using its drag and drop facilities.
Most of these a provided by default Motif drag and drop actions. Briefly the
- The middle mouse button must be used for drag and drop.
- A drag source can support multiple
operations. The user should be able to select the operation that is used. A key
selection in combination with the mouse button is typically used:
- -- selects a move operation.
- -- selects a copy operation.
- -- selects a link operation.
- -- cancels a drag at any time.
- -- should provide help information.
- Drag icons should be provided to indicate the three states of the
- A source indicator -- to indicate the primary data type for the draggable
- An operation indicator -- to indicate whether a move, copy or link
operation is occurring . A different icon should represent each type of
- A state indicator -- to indicate whether the a drop is valid.
Motif also provides guidelines on creating applications with consistent
interaction. If interaction is more or less uniform across applications then
the user can complete basic tasks more quickly. The Motif style guidelines on
user interaction are summarised as follows:
- Clearly Indicate Actions
- -- Interactions should be made as simple as
possible. Providing intuitive visual cues is a good way to achieve this. The
following principles should be adopted:
- Provide Feedback
- -- The user should always be informed of the current
state of the application. Labels and graphics as described above provide a good
means of conveying this information. Typical feedback mechanisms include:
- Showing progress -- if an actions takes some time to complete then a
WorkingDialog should be displayed. If the application can
monitor the progress of the action then it should update the WorkingDialog
- Providing warnings -- Certain actions can cause destructive actions. For
example closing an application before saving changes in a current file. The
user should be informed of such events via a WarningDialog .
- Providing help -- Help facilities should be provided for all
aspects interaction no matter how intuitive this may appear.
- Allow User Flexibility
- -- The user should be allowed flexibility to
adjust elements in the application. Elements that may require adjusting are
widget colour, fonts, default values, application parameters, key bindings,
labels, messages and even help facilities. Motif resources
(Chapter ) have been especially designed to allow
customisation of applications.
As we have already mentioned in Chapter the
of Motif has received ever increasing attention. In general many of the issues
governing internationalisation are local to a particular system configuration.
As we have seen the process of internationalisation can be a difficult process
and any tools available to aid this process should be used. Motif provides a
broad set of guidelines for the internationalisation of an application. However
most of the guidelines will be dependent on the available tools and system
configuration. Briefly the Motif style guidelines are as follows:
- Text Input
- -- Ideally international text input should be form a
keyboard that can provide all the characters of the local language. In some
cases a pre-edit step is needed where characters are initially typed in
an then converted to another set of characters. The system and application
programmers should take steps to make sure that this process is well supported
and well behaved. Where some conflict or confusion arises over a specific
conversion DialogBox should be used to convey the problem and list possible
choices in an appropriate menu.
- Country Specific Data Formats
- -- Various forms of data need to
supported by an application. Examples of data that varies in format
across countries include numeric (thousands, millions) and decimal point
separators, positive and negative values, currency, date and time formats,
telephone numbers, and names and addresses.
- Icons, Symbols and Pointers
- -- Graphical symbols cross borders more
easily than text labels. However, care may still be needed to make the graphic
symbols as cross-cultural as possible.
- Scanning Direction
- -- Readers of western languages scan from left to
right and from top to bottom. In other languages (e.g. Hebrew) readers
scan from right to left. This has major implication in the location of
components in menus and Dialog widgets. For example, should the help menu be
placed to the far right of the MenuBar.
- Modularise the Software
- -- If the application software can be
partitioned so that the text, input/output modules and other parts of the
code are separate then the application should be easier to internationalise as
individual modules can be substituted more easily.
- Clear Screen Text
- -- Well written screen text is far easier to
understand. Screen text should be simple and brief.