Chapter 12. Scripting Programs That Don't Have Dictionaries In every script since Chapter 1, you've used AppleScript commands that come from programs' dictionaries. Dictionaries are the cornerstone of application control (Section 3.2.2), and they're great for discovering new commands. The only problem is, not every program has as a dictionary. Some programs, like Chess, are too unimportant for Apple to create a dictionary. Others, like System Preferences, have such limited dictionaries that they're almost not worth mentioning. Still other programs are written by overworked third-party programmers, who might not fully comprehend the benefits of making their application AppleScriptable. And programs like Final Cut Pro and GarageBand really ought to have AppleScript dictionaries, but Apple hasn't gotten around to writing them. If you want to script such programs, you're left out in the coldor so you might think. The fact is, every programeven one without dictionariessupports three universal commands. They're not particularly powerful, but they form the backbone of most scripts. Table 12-1. Commands you can send to any program| Command | What it does |
|---|
activate
| Brings the target program forward, launching it if necessary. | launch
| Opens the target program but doesn't bring it forward. | quit
| Closes the target program, asking you to save any unsaved documents in the process. |
If you only used those three commands, however, you'd be left with some pretty dinky scripts. Of course, if the program you're controlling has a dictionary, the commands from that dictionary are likely to make up the vast majority of your script. Still, even if a program doesn't have a dictionary, you can control the program with AppleScript; it's just a little harder than usual. The trick is to use Mac OS X's GUI Scripting feature, through which you can control a program's interface (GUI, in fact, stands for Graphical User Interface). In essence, you use GUI Scripting to automate the clicking of buttons or the typing of keys, rather than directing programs with special commands like make or count.  | Even though you can control any program with GUI Scripting, you should use it only if the program you want to control doesn't have an AppleScript dictionary. That's because GUI Scripting is always slower and less reliable than scripting a program with direct AppleScript commands (as you've done in the last 11 chapters). |
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Gem in the Rough
Checking Whether a Program Has a Dictionary | When deciding how to script a program, it's important to know whether that program has a dictionary. If the program does, you can use any of the commands from that dictionary, automating your Mac with ease. On the other hand, if a program lacks a dictionary, you have to use GUI Scripting if you want to control the program with AppleScript. But you already knew all that. To figure out whether a program has a dictionary, you can make an educated guessor you can use the Finder's has scripting terminology property. You give that command a file alias, and you get back a Boolean value: true if the program has a dictionary or false if it doesn't. For example, you can use the following script to check whether TextEdit has a dictionary: tell application "Finder" if has scripting terminology of alias ¬ "Macintosh HD:Applications:¬ TextEdit.app:" then display dialog "Yes, TextEdit has ¬ a dictionary." else display dialog ¬ "TextEdit has no dictionary." end if end tell
To prove that the Chess program doesn't have a dictionary, simply replace the word "TextEdit" with "Chess" everywhere in the previous script. Or, if you'd like to check another program, substitute that program's name in the script instead. At a certain point, however, you'll get tired of editing your entire script just to check a different program. By making the following changes, however, you you'll be able to pick the program you want to check right from a dialog box: set selectedProgram to (choose file) . tell application "Finder" if has scripting terminology of selectedProgram thendisplay dialog ¬ "Yes, that program has a dictionary." else display dialog ¬ "That program does not have a dictionary." end if end tell
Incidentally, the benefit of this script over the File  Open Dictionary command is that it lets you pinpoint a particular program to check for a dictionary. If you used the Open Dictionary dialog box, you'd have to sort through dozens of programs just to find the one you want. |
| The example scripts from this chapter can be found on the AppleScript Examples CD (see Sidebar 2.1 for instructions). |
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