TweetFollow Us on Twitter

User Interface Scripting

Volume Number: 21 (2005)
Issue Number: 6
Column Tag: Programming

AppleScript Essentials

User Interface Scripting

by Benjamin S. Waldie

As we have seen in the past, AppleScript is a great tool for creating some pretty amazing automated workflows. When implementing an AppleScript-based workflow, you are really only limited by your imagination, and by the AppleScript support that is available in the applications that you want to automate.

Many scriptable applications offer enough AppleScript support for the types of tasks that you would want to automate the most. However, at times, you may find yourself needing to script an application with limited AppleScript support, and that one task you really need to automate just is not accessible through scripting. Or, worse yet, the application you want to automate is not scriptable at all!

How do you handle these limitations? Do you simply give up? I think not. For starters, you might check around to see if there are other scriptable applications that can be substituted to automate the same task.

Another option is to consider trying to automate the application by writing AppleScript code that interacts directly with the application's interface itself. Fortunately, with the release of Mac OS X 10.3, Apple introduced a new AppleScript feature, user interface scripting, or UI Scripting, which can be used to do just that.

What is UI Scripting?

UI Scripting is a feature in Mac OS X that provides a way for AppleScripts to interact directly with interface elements in running applications. For example, you might write a script that clicks a button in a window, selects a menu item in a popup menu, or types text into a text field of a non-scriptable application.

The AppleScript terminology for UI Scripting is not built into AppleScript itself, nor is it included in a scripting addition. Rather, UI Scripting is part of System Events, a background application that provides a central location for interacting with various aspects of Mac OS X itself, including running processes, or applications.

In order to view the AppleScript terminology for UI Scripting, open the dictionary for System Events by double clicking on it in the Script Editor's Library palette.


Figure 1. The Script Editor Library Palette and the System Events Dictionary

If you are using a different script editor, or prefer to open the dictionary by selecting File > Open Dictionary in the Script Editor menu bar, System Events can be found in the System > Library > CoreServices folder on your machine. In the System Events dictionary, UI Scripting-related terminology can be found under the Processes Suite. We will explore the UI Scripting terminology found in this suite shortly.

Enabling UI Scripting

Before writing code that makes use of UI Scripting in Mac OS X, you will first need to manually configure the machine on which the script will run, so that it can respond to UI Scripting commands. To enable UI Scripting, launch the System Preferences application, and click on the Universal Access button. Next, enable the checkbox labeled Enable access for assistive devices. See figure 2.


Figure 2. Universal Access Preference Pane

If the final destination for your script is another user's machine, then you should make sure that you provide that user with instructions for enabling UI Scripting on the machine prior to running the script. In order to ensure that the user actually follows your instructions, you may also want to add some code into your script to verify that UI Scripting has been enabled, and prevent the script from proceeding if it has not been enabled. You can tell if UI Scripting has been enabled by checking the value of the UI elements enabled property of the System Events application. This property will contain a true or false value, indicating whether or not UI Scripting is enabled.

The following example code will check to see if UI Scripting is enabled. If it is not enabled, the script will launch System Preferences, display the Universal Access pane, and notify the user that the Enable access for assistive devices checkbox must be enabled in order to proceed.

tell application "System Events" to set isUIScriptingEnabled to UI elements enabled
if isUIScriptingEnabled = false then
   tell application "System Preferences"
      activate
      set current pane to pane "com.apple.preference.universalaccess"
      display dialog "Your system is not properly configured to run this script.  
         Please select the \"Enable access for assistive devices\" 
         checkbox and trigger the script again to proceed."
      return
   end tell
end if

-- Add your code here, which will be triggered if UI Scripting is enabled

UI Scripting Terminology

As previously mentioned, the AppleScript terminology for UI Scripting is found under the Processes Suite in the System Events dictionary. Here, you will find a variety of classes, or objects, along with a few commands. Let's briefly discuss the commands first. We'll see them in action a little later.

Commands

There are only a handful of commands that you will use for UI Scripting, and they are click, key code, keystroke, perform, and select. In this article, I am going to touch on the click and keystroke commands, as they are what I have found to be particularly useful, and I have chosen to include them in the examples at the end of this article.

As one would expect, the click command is used to simulate the user clicking on an interface element. For example, you might use the click command to click a button on a window.

click button 1 of window 1

The keystroke command is used to enter keystrokes, as if they were typed by a user. The keystroke command also offers the ability, through an optional parameter, to specify modifier keys that should be invoked when the command is executed. For example, you may need to simulate the process of holding down the command key while typing a key.

keystroke "P" using {command down}

Again, these are just very brief introductions to two commands that can be used to interact with interfaces. You should spend some time exploring the other commands on your own, in order to become familiar with them. Now, let's take a look at some of the classes listed under the Processes suite of the System Events dictionary.

The Process Class

When working with UI Scripting, the top-level class you will address is the process class. A process signifies any process, or application, that is currently running on the machine. To get the names of any currently running processes, use the following syntax:

tell application "System Events" to return name of every process

--> {"loginwindow", "Dock", ... "Finder", "Preview", "Script Editor"}

Processes possess a variety of properties, which can be accessed through AppleScript. One such property is the frontmost property. In some cases, you may need to bring a process to the front in order to interact with its interface. This can be done by setting the frontmost property of the process to a value of true. For example, the following code brings the application Preview to the front.

tell application "System Events" to set frontmost of process "Preview" to true

Note in this example that I refer to the Preview application as a process of the System Events application. Be sure to explore the other properties of processes, as well, as they can provide other important information to your script.

I have chosen to use Preview for the examples in this article, since Preview is not AppleScriptable, and since it is installed with Mac OS X.

UI Element Classes

A process with an interface typically contains a variety of interface elements, such as windows, buttons, text fields, and more. These are the elements with which you will primarily want your script to interact.

In the System Events dictionary, a UI Element is, in itself, a class, and possesses a variety of properties common to most interface elements. For example, since many interface elements possess the ability to be enabled or disabled, an enabled property can be found under the more generic class of UI Element. Processes also inherit some properties from this class.

There are a number of different classes of interface elements in the Processes suite. If you have used AppleScript Studio in the past, then you will no doubt be familiar with the names of at least a few of them, although the exact naming may be slightly different from that of AppleScript Studio. Some of the more commonly accessed classes of interface elements include checkboxes, menus, menu items, pop up buttons, radio buttons, text fields, and windows. As mentioned above, since all interface elements possess certain characteristics, each class of interface element inherits properties from the UI Element class.

Be sure to browse through the various classes of interface elements listed in the Processes suite.

Referring to UI Elements

Just like scripting any object in a scriptable application, when writing code to interact with an interface, you must address the interface elements within their object hierarchy. Deciphering an object's hierarchy within a process' interface is usually no small feat. For basic interfaces, it may be as simple as referring to an interface element on a specific window. However, for more complex interfaces, it can quickly become a long set of nested object references.

Let's take a look at an example. The following code will click the Drawer button in the tool bar of an opened document in Preview, toggling the drawer opened or closed.

tell application "System Events"
   tell process "Preview"
      click button "Drawer" of tool bar 1 of window 1
   end tell
end tell

You can see from this example that in order to interact with the Drawer button, you must indicate specifically where the button is located within the interface. In this case, it is on the tool bar of the front window.

There is some good news, though. Apple doesn't leave you high and dry to figure out these object hierarchies on your own. There is a tool available to help. It is called UI Element Inspector, and it can be downloaded from Apple's AppleScript web site <http://www.apple.com/applescript/uiscripting/>.


Figure 3. UI Element Inspector

When launched, UI Element Inspector floats above all interfaces, and displays information about the interface elements located directly below the mouse pointer. Information displayed includes the location of the interface element, within its object hierarchy, along with values from various properties. In figure 2, UI Element Inspector is indicating the exact location of the Drawer button in a Preview window - within a tool bar, which is within a window of the application. As you can see, the tool bar itself does not possess a specific name, which is why I referred to it as tool bar 1 in my code.

Examples

Now, let's take a look at some examples of UI Scripting in action. The following example code assumes that you have a document opened in Preview. When this code is run, it will bring Preview to the front and print the front window.

tell application "System Events"
   tell process "Preview"
      set frontmost to true
      click menu item "Print..." of menu "File" of menu bar 1
      repeat until sheet "Print" of window 1 exists
      end repeat
      keystroke return
   end tell
end tell

The following example code assumes that you have a document opened in Preview. When this code is run, it will bring Preview to the front and export the front window to the desktop in TIFF format.

tell application "System Events"
   tell process "Preview"
      set frontmost to true
      keystroke "E" using {command down, shift down}
      repeat until sheet 1 of window 1 exists
      end repeat
      tell sheet 1 of window 1
         keystroke "Output"
         keystroke "D" using command down
         tell pop up button 1 of group 1
            click
            tell menu 1
               click menu item "TIFF"
            end tell
         end tell
         delay 1
         click button "Save"
      end tell
   end tell
end tell

Limitations

UI Scripting is based on Mac OS X's accessibility framework, which is why it must be enabled from the Universal Access preference pane. Because it is based on the accessibility framework, UI Scripting can only interact with applications that have been updated to support this framework. The accessibility framework was first released with Mac OS X 10.2, so many applications have accessibility support built-in by now. However, some applications do not, and may not respond to UI Scripting terminology. To automate applications that do not support UI Scripting, you may need to turn to other tools, such as QuicKeys <http://www.quickeys.com>.

A Third Party Assistant

While UI Element Inspector provides some much needed input for writing your AppleScript code, a third-party application takes it a step further.

PreFab UI Browser, a commercial application available from PreFab Software, Inc., offers all of the functionality of the UI Element Inspector, and a lot more. PreFab UI Browser provides robust interfaces designed for the serious scripter, making it easy to access information about the complete interface of any accessible running application. Other features of PreFab UI Browser include the ability to trigger hot keys to enable and disable interface element browsing, auto-generation of AppleScript code to interact with interface elements, and much more. Be sure to visit the PreFab Software, Inc. web site <http://www.prefab.com> for more information about this tool, or to download a demo version. While you're there, be sure to check out another product - PreFab UI Actions. This tool will allow you to configure AppleScripts to trigger automatically whenever specific user interface actions occur in an application. For example, you could configure an application to trigger a script whenever a user selects the Save As from the File menu. The possibilities are limitless.

In Closing

As you can see, UI Scripting can be quite a useful tool when trying to automate an application that doesn't provide the AppleScript support that you need. So, before you decide that just because an application isn't scriptable, it can't be automated with AppleScript, be sure to check out its interaction with UI Scripting.

In my experience, there is not much on the Mac that can't be automated... one way or another. Until next time, keep scripting!


Benjamin Waldie is president of Automated Workflows, LLC, a firm specializing in AppleScript and workflow automation consulting. In addition to his role as a consultant, Benjamin is an author for SpiderWorks, LLC and an evangelist of AppleScript. He can often be seen presenting at Macintosh User Groups, Macworld Expos, and more. For additional information about Benjamin, please visit http://www.automatedworkflows.com, or email Benjamin at applescriptguru@mac.com.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Tunnelblick 3.7.4b - GUI for OpenVPN.
Tunnelblick is a free, open source graphic user interface for OpenVPN on OS X. It provides easy control of OpenVPN client and/or server connections. It comes as a ready-to-use application with all... Read more
Carbon Copy Cloner 5.0.5 - Easy-to-use b...
Carbon Copy Cloner backups are better than ordinary backups. Suppose the unthinkable happens while you're under deadline to finish a project: your Mac is unresponsive and all you hear is an ominous,... Read more
Postbox 5.0.22 - Powerful and flexible e...
Postbox is a new email application that helps you organize your work life and get stuff done. It has all the elegance and simplicity of Apple Mail, but with more power and flexibility to manage even... Read more
Ortelius 2.0.8 - Vector drawing app espe...
Ortelius is a full-featured vector drawing application especially for map design. Draw directly with features such as roads, rivers, coastlines, buildings, symbols and contours. Ortelius is known for... Read more
Bartender 3.0.32 - Organize your menu-ba...
Bartender lets you organize your menu-bar apps by hiding them, rearranging them, or moving them to Bartender's Bar. You can display the full menu bar, set options to have menu-bar items show in the... Read more
Adobe Animate CC 2018 18.0.1.115 - Anima...
Animate CC 2018 is available as part of Adobe Creative Cloud for as little as $19.99/month (or $9.99/month if you're a previous Flash Professional customer). Animate CC 2018 (was Flash CC) lets you... Read more
Adobe Lightroom Classic CC 7.1 - Import,...
Adobe Lightroom is available as part of Adobe Creative Cloud for as little as $9.99/month bundled with Photoshop CC as part of the photography package. Lightroom 6 is also available for purchase as a... Read more
ExpanDrive 6.1.8 - Access cloud storage...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
ExpanDrive 6.1.8 - Access cloud storage...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
DiskCatalogMaker 7.2.7 - Catalog your di...
DiskCatalogMaker is a simple disk management tool which catalogs disks. Simple, light-weight, and fast Finder-like intuitive look and feel Super-fast search algorithm Can compress catalog data for... Read more

Latest Forum Discussions

See All

Amazing Katamari Damacy guide - beginner...
Amazing Katamari Damacy brings the bizarro world of the original games to mobile and shifts them into an endless format that's just as addictive as the PlayStation entries. Your goal is still to roll as much random stuff as you possibly can, though... | Read more »
Portal Knights guide - crafting tips and...
In Portal Knights, you're only as strong as the items you have at your disposal. This sandbox adventure is all about crafting and building up the next big thing. Whether you're an avid explorer or collector, crafting will likely play a large part... | Read more »
The best deals on the App Store this wee...
A new week means new discounts on the App Store. This week's deals run the gamut of action-adventure titles, puzzle games, and one of the best narrative adventure series out there. If you're looking to fill out your mobile gaming library on a... | Read more »
What you need to know about Animal Cross...
We hope you've been hard at work on collecting all of those holiday items in Animal Crossing: Pocket Camp, because you're about to get a whole new list of fun things to do as the game receives its first big update sometime soon. There are a lot of... | Read more »
Reigns: Her Majesty guide - how to use e...
Ruling a kingdom isn't easy--doubly so for a queen whose every decision is questioned by the other factions seeking a slice of power. Reigns: Her Majesty builds on the original game's swipey tactics, adding items that you can use to move the story... | Read more »
The best new games we played this week -...
Friday has crept up on us once again, so it's time to honor the best new games we've played over the past few days. This past week was a pretty exciting one, with the debut of lots of beautiful new indies and some familiar faces returning to the... | Read more »
Portal Knights guide- beginner tips and...
Portal Knights is finally making the jump to iOS and Android, and it's already climbing the ranks to become the next big MMO experience on mobile. This sprawling sandbox game will let you pursue any adventure you wish, whether you want to sling... | Read more »
Reigns: Her Majesty guide - how to swipe...
Reigns: Her Majesty is storming the App Store this week, bringing more tinder-esque kingdom building to eager players everywhere. If you've played the original Reigns, you'll know that leading a kingdom is never easy. It's a careful balancing act... | Read more »
Getting Over It (Games)
Getting Over It 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: A game I madeFor a certain kind of person To hurt them. • Climb up an enormous mountain with nothing but a hammer and a pot.•... | Read more »
Reigns: Her Majesty (Games)
Reigns: Her Majesty 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: | Read more »

Price Scanner via MacPrices.net

Apple Watch Series 2, Certified Refurbished,...
Apple has Certified Refurbished Apple Watch Nike+ Series 2s, 42mm Space Gray Aluminum Case with Anthracite/Black Nike Sport Bands, available for $249 (38mm) or $279 (42mm). The 38mm model was out of... Read more
Apple offers Certified Refurbished 2016 12″ R...
Apple has Certified Refurbished 2016 12″ Retina MacBooks available starting at $949. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The following... Read more
B&H drops price on 13″ 256GB MacBook Air...
B&H has the 13″ 1.8GHz/256GB Apple MacBook Air (MQD42LL/A) now on sale for $1079 including free shipping plus NY & NJ sales tax only. Their price is $120 off MSRP, and it’s the lowest price... Read more
Holiday sale: 9″ iPads starting at $299, take...
MacMall has 9″ WiFi iPads on sale for $30 off including free shipping: – 9″ 32GB WiFi iPad: $299 – 9″ 128GB WiFi iPad: $399 Read more
Green Monday deal: 15″ 2.8GHz MacBook Pro on...
B&H Photo has the 15″ 2.8GHz Space Gray MacBook Pro on sale for $250 off MSRP for today only as part of their Green Monday/Holiday sale. Shipping is free, and B&H charges sales tax for NY... Read more
Green Monday sale: B&H offers 12″ Apple i...
B&H Photo has 12″ iPad Pros on sale for up to $150 off MSRP as part of their Green Monday/Holiday sale. Shipping is free, and B&H charges sales tax in NY & NJ only: – 12″ 64GB WiFi iPad... Read more
Holiday deal: 21″ and 27″ Apple iMacs on sale...
MacMall has 2017 21″ and 27″ Apple iMacs on sale for up to $200 off MSRP. Shipping is free: – 21″ 2.3GHz iMac: $999 $100 off MSRP – 21″ 3.0GHz iMac: $1199 $100 off MSRP – 21″ 3.4GHz iMac: $1379 $120... Read more
Holiday deal: Apple Mac minis for up to $150...
MacMall has Mac minis on sale for up to $100 off MSRP, each including free shipping: – 1.4GHz Mac mini: $399 $100 off MSRP – 2.6GHz Mac mini: $599 $100 off MSRP – 2.8GHz Mac mini: $949 $50 off MSRP... Read more
Beats by Dr. Dre – BeatsX Earphones on sale f...
Best Buy has BeatsX Earphones on sale for $109, $40 off, on their online store. Sale price for online orders only. Choose free store pickup, if available, or choose free shipping. Read more
10″ 64GB WiFi Apple iPad Pros on sale for $59...
MacMall has 10.5″ 64GB Apple iPad Pros on sale for $599 including free shipping. That’s $50 off MSRP and among the lowest prices available for these iPads from any Apple reseller. Read more

Jobs Board

QA Automation Engineer, *Apple* Pay - Apple...
# QA Automation Engineer, Apple Pay Job Number: 113202642 Santa Clara Valley, California, United States Posted: 11-Dec-2017 Weekly Hours: 40.00 **Job Summary** At Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Information Security - Security Data...
# Apple Information Security - Security Data Analyst Job Number: 113119545 Austin, Texas, United States Posted: 10-Nov-2017 Weekly Hours: 40.00 **Job Summary** This Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.