objective c - How do I add Applescript support to my Cocoa application?

Question

I am new to the world of Cocoa programming, and I want to add Applescript support to my application. The examples at Apple's website seem out of date.

How do I add Applescript support to my Cocoa application?

Answer 1

1. If you want to send AppleScript from your application and need a sandboxed app, you need to create a temporary entitlement

2. You need to add those two keys in your info.plist

   <key>NSAppleScriptEnabled</key>
   <true/>
   <key>OSAScriptingDefinition</key>
   <string>MyAppName.sdef</string>
   

...of course you have to change "MyAppName" to your app's name

3. Create a .sdef file and add it to your project. The further course now greatly depends on the needs of your application, there are:

   1. Class Elements (create an object from AppleScript)
   2. Command Elements (override NSScriptCommand and execute "verb-like" commands)
   3. Enumeration Elements
   4. Record-Type Elements
   5. Value-Type Elements (KVC)
   6. Cocoa Elements

   -

   Go here to find a detailed description and many details on their implementation: https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/ScriptableCocoaApplications/SApps_script_cmds/SAppsScriptCmds.html

4. I found working with Class and KVC Elements very complicated, as I just wanted to execute a single command, nothing fancy. So in order to help others, here's an example of how to create a new simple command with one argument. In this example it'll "lookup" one string like this:

   tell application "MyAppName"
       lookup "some string"
   end tell
   

5. The .sdef file for this command looks like this:

   <?xml version="1.0" encoding="UTF-8"?>
   <!DOCTYPE dictionary SYSTEM "file://localhost/System/Library/DTDs/sdef.dtd">
   
   <dictionary title="MyAppName">
       <suite name="MyAppName Suite" code="MApN" description="MyAppName Scripts">
           <command name="lookup" code="lkpstrng" description="Look up a string, searches for an entry">
               <cocoa class="MyLookupCommand"/>
               <direct-parameter description="The string to lookup">
                   <type type="text"/>
               </direct-parameter>
           </command>
       </suite>
   </dictionary>
   

6. Create a subclass of NSScriptCommand and name it MyLookupCommand

   The MyLookupCommand.h

   #import <Foundation/Foundation.h>
   
   @interface MyLookupCommand : NSScriptCommand
   
   @end
   

   The MyLookupCommand.m

   #import "MyLookupCommand.h"
   
   @implementation MyLookupCommand
   
   -(id)performDefaultImplementation {
   
       // get the arguments
       NSDictionary *args = [self evaluatedArguments];
       NSString *stringToSearch = @"";
       if(args.count) {
           stringToSearch = [args valueForKey:@""];    // get the direct argument
       } else {
           // raise error
           [self setScriptErrorNumber:-50];
           [self setScriptErrorString:@"Parameter Error: A Parameter is expected for the verb 'lookup' (You have to specify _what_ you want to lookup!)."];
       }
       // Implement your code logic (in this example, I'm just posting an internal notification)
       [[NSNotificationCenter defaultCenter] postNotificationName:@"AppShouldLookupStringNotification" object:stringToSearch];
       return nil;
   }
   
   @end
   

   That's basically it. The secret to this is to subclass NSScriptCommand and override performDefaultImplementation. I hope this helps someone to get it faster...