On disk, a Plugin is just a folder arranged in a standard layout.
It contains one or more scripts. Each script defines one or more commands which extend Sketch in some way. It can also contain any other optional resources (such as images) that the commands make use of to do whatever they do.
Before we get any further, let’s define a bit of terminology.
- Plugin: a collection of Scripts, Commands and other resources grouped together as a discrete unit
- Plugin Bundle: the folder on disk containing the files that make up the Plugin
- Action: something the user does (selecting a menu, or changing the document) which triggers a Command
- Command: a Plugin can define more than one command; typically each one is associated with a different menu or keyboard shortcut, and causes a different Handler to be executed.
- Handler: a CocoaScript function which executes some code to implement a Command.
- Script: a CocoaScript file containing one or more Handlers which implement one or more Commands.
How Do I Make A Plugin?
By now, probably you’re wondering how to get started writing your own.
Often the best place to start is with some existing examples. With this in mind, we’ve included Some Example Plugins along with this documentation.
These aren’t intended to actually be massively useful additions to Sketch, but they illustrate how to get a Plugin working, and can be copied to form the basis of something new.
The Resources page also lists some good places to find other Plugins.