Mac OS X Services
Volume Number: 20 (2004)
Issue Number: 12
Column Tag: Programming
Mac OS X Services
Revisiting an Old Favorite
by Clint Bagwell
Remember the Services menu? It was one of the then-new features advertised with the coming of the
first version of OS X. Three generations later Services are still a core component of the
contemporary Mac OS and also one of its best kept-secrets. Developers and power users know about
Services' system-wide, interactive functionality, but home users can also make the most of their
many practical uses.
About Services
Services were one of the many NEXT innovations that were incorporated into the first version of
OS X. Services can be found under any native OS X program's Application menu. The Services menu
extends an application's functionality by providing some of its own capabilities to other programs.
When an application signs up for Services, it takes advantage of another application's abilities as
well. This feature is made possible by transferring data through a shared pasteboard (which exists
independently of the normal Copy/Paste pasteboard). Apple includes some services as part of its
operating system, and makes it easy for developers to use the technology in their own applications.
When using more than one application, Services can improve workflow efficiency to save time.
Let's look at a practical example using just the Services that are already built in to OS X. You
get a confirmation email from an order you placed online. With the email open in Mail, you select
the confirmation number and choose Make New Sticky Note from the Service menu. Stickies
automatically opens and creates a new note containing the confirmation number to view later. The
email includes a number to track the package on a website, but leaves the URL incomplete so it is
not an active link. No problem. You select "USPS.com" in the message and choose Open URL under the
Services menu. Safari opens and is intelligent enough to locate http://www.usps.com/ for you. Daily
tasks like these become less cumbersome with the Services menu's seamless integration of often used
applications. Apple also includes many other helpful services that make use of the Finder, Mail,
TextEdit, and Safari. The Grab application's Services are popular, as they provide an easy way to
take screen shots from another application. Another Service that is often mentioned is Start
Speaking Text. The simple command enables the power of OS X's speech center to aid in editing text.
This tool is invaluable for catching mistakes that your eye may have missed. These are just a few of
the helpful Services tied in to OS X's bundled applications.
Unfortunately, whenever I introduce someone to Services, they get really excited about it for
five minutes and never use them again. Sound familiar? Let's face it, the Services menu has its pros
and it definitely has its unfortunate cons. The biggest complaint I hear are that Services are not
always available. It is up to the application developer to support it or not (Microsoft, I am
looking in your direction...) To be fair, you may be surprised to hear that AppleWorks doesn't use
them either. On top of this, many users get confused because you usually must have something
selected in order for the Services to become active. The Services menu makes system-wide shortcuts
available (Search With Google is Command+Shift+L), a plus in my book. On the other hand, Apple
leaves it up to the developer to define the keyboard command, a definite problem. A user can easily
wind up with two services trying to use the same shortcut. I will go over some ways to work around
this issue later in the article.
Ready-Made Toolbox
We have looked at the services already included in OS X; a user can even further enhance
productivity with add-ons. Devon Technology's "Service Pack" is my favorite set of downloadable 3rd
party services. In WordService, Devon has created a variety of useful tools for manipulating,
inserting, or analyzing text. Developers take note of items like Mac- to Windows-Encoding or Unix
Line Endings. The average user may find that Initial Caps Of Sentences, Insert Long Date and Time or
Statistics will add more power to the TextEdit program, and make him less dependent on Microsoft
Word (http://www.devon-
technologies.com/products/freeware/freeware.php).
If you routinely handle sensitive data, consider Security Service from Ambriel Software. The
standard version adds the ability to encrypt or shred a file that is selected in the Finder. The pro
version beefs up encryption options and enables others such as "Free Space Shredding" (http://ambrielsoftware.com/products/
security_services/).
If all of these tools aren't enough for you, push the Services menu over the top with the more
than 120 that come with Text Wielder from Tinnef Software. In addition to text formatting tools
similar to those of WordService, it includes research options such as Search Apple Help, Phone
Number - Reverse Lookup at AnyWho.com, and package tracking from several providers. A word of
advice: saturating the Services menu can drastically increase login times, as OS X searches for all
that are available. Luckily, Text Wielder comes with the ability to activate or deactivate its
abundance of menu options. Power users may take interest in the scalability of this program: Text
Wielder gives them the ability to create additional Service menu items by harnessing the power of
AppleScript and SFRL (Simple Find and Replace Language) (http://www.commongrnd.com/~blenkush/
textwielder.html).
Roll Your Own: Customizing And Creating Services
So what makes up a Service menu item? Add-on Services like WordService are installed by dragging
.service files to /Library/Services or ~/Library/Services, but Services that are part of another app
are typically part of its information property list. It is the Info.plist file within the Package's
Contents directory that declares how an application's services appear in the Services menu and what
type of data it can handle. When you open this file in a text editor (reminder: always backup your
application before editing) you will look for the property called NSServices, and with it the
components that make up a Service menu item. Remember that pesky issue of two applications using the
same keyboard shortcut? Take a look at the example below:
<key>NSKeyEquivalent</key>
<dict>
<key>default</key>
<string>B</string>
</dict>
Changing the B between the string tags to another character will change that menu item's shortcut
to whatever you choose. (Keep in mind that OS X will automatically add Command+Shift to your
character in the menu).
For the coding-challenged, PearSSC from Pearworks will do all of this with a graphical interface.
Drag the application to the PearSSC window and type a letter; not only is it easy, it's free (http://www.pearworks.com/pages/software.html
).
Ready to take Services to the Extreme?
If you like using the command line, you will love SilverService by Rob Hague. This application
consists of a panel that holds a list of your own Shell commands (complete with title, input, and
output). SilverService then lists your commands by title under its own Service menu (http://www.rho.org.uk/software/silverservice/).
Similarly, ACP Web Services harnesses the power of search queries for its convenient and
customizable Service menu. This application is based on the premise that most search engines use a
query string with the desired word or phrase tacked onto the end of it (example:
http://www.google.com/search?q=apple). So when you select a word in TextEdit and activate one of the
ACP Services, it pastes your selection onto the end of its string to form a complete URL. To
customize, write your own query or simply copy it from a search made on your favorite website, and
add it to the APC list (in the above example you would copy the URL minus the word apple). What's
more, ACP Web Services includes a "grab bag" of pre-built services ranging from Traceroute to a
variety of international language Google searches. The pro version also adds a full service manager
and shortcut editor for the entire Services menu (http://rixstep.com/4/0/aws/).
Developer Note:
Why should developers pay attention to the Services menu? Consider this example: MarketCircle
utilized Services to creatively boost functionality to DayLite, a popular CRM application for Mac OS
X. It features the ability to send e-mails to customers natively from the application, while
recording the text in its database. Users naturally requested the ability to record incoming emails
into the database as well, to capture their customers' responses. Rather than turn DayLite into a
full-fledged e-mail client, MarketCircle simply added Services that work cleanly with Mail and other
Services-aware applications. The user selects text and chooses the appropriate Service to create a
note, task, or appointment in DayLite. When asked about their use of Services, MarketCircle's
president Alykhan Jetha had this to say: "We decided to use the Services menu because of the its
power. We realized the value of the Services architecture during our NeXT days."
If you're a developer, it's in your best interest to take another look at Services. Offer
interactivity with other applications to make your application more beneficial without creating an
entire plug-in or rewriting your app altogether. Think of the Services Menu as a great location for
us to access your program's capability system-wide without crowding our menubars with extra icons.
And by the way, it's not just for Cocoa anymore!
For More Information on Developing Services:
Clint Bagwell is a freelance Macintosh Consultant and visual artist working in New
York City. For more information go to http://appleconsulting.net/bagwell
