My Sunday Project - Reusable Cocoa Script Menu

The Sunday Project

So last sunday I started on something new, really it’s a feature for NicePlayer, but also a feature in a lot of other existing apps out there, and could be useful in a lot of cocoa programs that don’t have this feature yet, so I wrote my implementation as an embedable framework, and am releasing under the MPL/LGPL/GPL (my latest preferred OSI approved license for those who notice what license I release under).

So here’s a riddle, what do iTunes, DVD Player, Xcode, FlySketch, NetNewsWire, MarsEdit and BBEdit all have in common?

Give up?

They all have one of these (more or less):

Their own script menu.

Uses in NicePlayer

Having a script menu in NicePlayer has been something in the back of my mind for a while. There are some features requests, while really simple, are very specific to individual user needs and we can’t justify adding a feature. Sometimes there are features requests that just don’t fit into Robert’s or my idea of NicePlayer, and we barely have enough time to add the features we want to add, so in the next release users can add their own menu commands in this script menu.

One of the features introduced in 0.92 of NicePlayer was an option to remove the fixed aspect ratio. Maybe you want to distort the movie, maybe the aspect ratio is just slightly off, this feature works in those cases, and only adds one more menu to the window and is inline with adding basic window options in the Window menu that we did before. However this isn’t useful when someone has a lot of media that is consistently using non-square pixels. In the case of standard media formats, the proper behavior of NicePlayer should be to automatically adjust (this feature has been added for the DV codec when using the CoreVideo plugin in the next version of NicePlayer 0.93). However there are people out there for some reason, how have media that is encoded with non-square pixels for no standard reason, and there isn’t a way to detect the correct aspect ratio. It turns out writing an AppleScript with the current NicePlayer dictionary to set a Window to a different aspect ratio is pretty trivial, so this is one of the scripts we’ll likely include in the next release (since its one the scripts i’ve been using to test anyway).

I think the main benefit of having the script menu, will be nicer integration with other apps. Whether having it integrate with a cataloging app, Toast, or just organizing with the finder, there seem to be many potential uses in this respect.

CocoaScriptMenu.Framework in Your Own Program

The framework is called CocoaScriptMenu.Framework and available on my software page. It’s not my favorite name of the software I’ve written, but I think it’ll help in being google-able for those wanting it’s feature. I’m releasing it as version 1.0, and as I said before under the MPL/LGPL/GPL license. The basic way to use it is to:

1. Add the framework binary to your project
2. Add the framework to a copy phase that puts it into the Frameworks folder of your app bundle
3. Add this line [[CSMScriptMenu sharedMenuGenerator] updateScriptMenu]; somewhere right after the nib loads (while including <CocoaScriptMenu/CocoaScriptMenu.h> for that file of course)

And that will give you a typical script menu once you compile and run your app.

Features

I wrote typical, as not all script menus are the same. I tried to add what I felt were the best features of all the script menus, while being able to behave, depending on how you use it, like 80% of the script menus I’ve seen with out any extra customization. Some of the features are

• It looks for scripts in Application Support/AppName/Scripts in all domains.
• You can make submenus by nesting folders.
• You can add a menu separator by adding a file or folder with a dash as it’s name.
• You can order scripts, separators, and folders using a two digit prefix on the file name (two digit prefix not required).
• It runs AppleScripts, Automator Files (.workflow), Application Bundles, and Shell Scripts (sh/python/perl/whatever but remember you need executable permission for shell scripts).
• It automatically updates the menu, without relaunching the application, as you add items or folders nested inside the script folder, unless that folder didn’t exist at Application Launch.

Extending w/o Modifying

The singleton [CSMScriptMenu sharedMenuGenerator] has 4 optional delegate methods that allow you to keep the core functionality but make some slightly different script menus without having to modify the source (although modification is certainly an option. (warning most of this is untested as I use only the default implementation of each of these in NicePlayer)

-(NSMenuItem*)showScriptFolderMenuItem;

If your delegate implements this method, it needs to return a NSMenuItem that should be used instead of the Open Scripts Folder menu item. An example would be a menuitem with a submenu with an open command for each each script folder in the domains. The default behavior is a menuitem to open the first location returned by the delegate method -(NSArray*)scriptLocations; in the finder.

-(NSArray*)argumentsForShellScripts;
The default implementation returns nil. Implement this method in your delegate if you want to pass string arguments to any shell script. (is not used for AppleScripts, Application Bundles or Workflows)

-(id)scriptMenuItemOrItems;
This should return something that has a subMenu or menu getter for an NSMenu. This NSMenu is what the script menu items get added too. You may also return an array to add the script menu in multiple places in your app. The default implementation adds a Script Menu in-front of the Help menu and returns it.

-(NSArray*)scriptLocations;
The default implementation, returns the paths to Application Support/MainBundleName/Scripts for every domain that the path exists, with the User domain guaranteed first. Also creates the folder for the user domain if it doesn’t exist.

Extending by Modifying

So in version 1.0 the script running implementations are very basic. They are setup as a Class Cluster, with the CSMCommand class providing the public interface and several subclasses that implement script running for various types of scripts or executables.

Diagram of class hierarchy:

alloc on CSMCommand returns a singleton instance of CSMPlaceholderCommand. CSMPlaceholderCommand’s initWithScriptPath: works as parameterized factory method and depending on the path passed in returns the correct concrete implementation allocated and initialized.

So to extend the implementation of script execution for an existing file type, you would just modify one of the subclasses. To add a new filetype you would modify the initWithScriptPath: factory method and add a new subclass.

initWithScriptPath: uses Apple’s Uniform Type Identifiers to determine which concrete class to instantiate, so order does matter, make sure you add the more specific type checks in the beginning of the method and the more general towards the end.

There are a lot of ways that I can think of that the concrete script execution classes could be improved, however for NicePlayer these all work well, thus I figured for version 1.0 it was better to stick with the basic implementation and release it now, rather than try and over engineer. So I’ll wait and see if people need more or not, not to mention they have the option of contributing code.

Updated at Cocoa Script Menu Revised 1.01