What is this?

This is a sample implementation of IMKit App with Swift/SwiftUI.

Working Environment

Check in July 2022.

• macOS 12.4
• Swift 5.6
• Xcode 13.4.1

Check in 2021.

• macOS 11.5
• Swift 5.5
• Xcode13 (beta)

Usage

To try this sample project, use following steps.

• Open this project in Xcode.
• Do sudo chmod -R 777 /Library/Input\ Methods on terminal.
• Run the project.
• Add 'IMKitSample' in setting > keyboard > input source > English.
• Choose IMKitSample as input source and try it on some text field.

Procedure to make project

I used following steps to prepare this sample project.

• Create new project. Bundle Identifier must contain .inputmethod. part in the String.

• Run.

• Remove IMKitSampleApp.swift, ContentView.swift

• Add Swift files AppDelegate.swift and IMKitSampleInputController.swift.

  // AppDelegate.swift
  import Cocoa
  import InputMethodKit
  
  // necessary to launch this app
  class NSManualApplication: NSApplication {
      private let appDelegate = AppDelegate()
  
      override init() {
          super.init()
          self.delegate = appDelegate
      }
  
      required init?(coder: NSCoder) {
          fatalError("init(coder:) has not been implemented")
      }
  }
  
  @main
  class AppDelegate: NSObject, NSApplicationDelegate {
      var server = IMKServer()
      var candidatesWindow = IMKCandidates()
  
      func applicationDidFinishLaunching(_ notification: Notification) {
          // Insert code here to initialize your application
          server = IMKServer(name: Bundle.main.infoDictionary?["InputMethodConnectionName"] as? String, bundleIdentifier: Bundle.main.bundleIdentifier)
          candidatesWindow = IMKCandidates(server: server, panelType: kIMKSingleRowSteppingCandidatePanel, styleType: kIMKMain)
          NSLog("tried connection")
      }
  
      func applicationWillTerminate(_ notification: Notification) {
          // Insert code here to tear down your application
      }
  }

  // IMKitSampleInputController.swift
  import Cocoa
  import InputMethodKit
  
  @objc(IMKitSampleInputController)
  class IMKitSampleInputController: IMKInputController {
      override func inputText(_ string: String!, client sender: Any!) -> Bool {
          NSLog(string)
          // get client to insert
          guard let client = sender as? IMKTextInput else {
              return false
          }
          client.insertText(string+string, replacementRange: NSRange(location: NSNotFound, length: NSNotFound))
          return true
      }
  }

• Add icon file main.tiff.

• Modify Info.plist

  key: NSPrincipalClass  type: _  value: $(PRODUCT_MODULE_NAME).NSManualApplication
  key: InputMethodConnectionName  type: String  value: $(PRODUCT_BUNDLE_IDENTIFIER)_Connection
  key: InputMethodServerControllerClass  type: String  value: $(PRODUCT_MODULE_NAME).IMKitSampleInputController
  key: Application is background only  type: Boolean  value: YES
  key: tsInputMethodCharacterRepertoireKey  type: Array  value: [item0: String = Latn]
  key: tsInputMethodIconFileKey  type: String  value: main.tiff
  

• Add entitlements

  • Go Signing & Capabilities → +Capability → App Sandbox

  • Go IMKitSample.entitlements, add

    key: com.apple.security.temporary-exception.mach-register.global-name
    type: String
    value: $(PRODUCT_BUNDLE_IDENTIFIER)_Connection
    

• Do sudo chmod -R 777 /Library/Input\ Methods on terminal.

• Modify build settings.

  • Go Build Locations → Build Products Path of debug → value /Library/Input Methods
  • Go + → Add User-Defined Setting → Set key CONFIGURATION_BUILD_DIR, value /Library/Input Methods.
  • !!! DO NOT edit thinklessly, this setting is really fragile.

• Try Run.

Trouble Shooting

I'm not an expert of macOS. Please don't ask too much, I don't know either.

• InputMethods says connection **Failed** all though there are no diff!

  • Open 'Activity Monitor' app, search the name of your InputMethods, and kill the process. Then try again.

• print() doesn't work!

  • Use NSLog().

• App doesn't run!

  • Check the path of build product file. If it isn't at /Library/Input Methods/..., something went wrong.
  • Maybe build setting went wrong. Check the settings. Especially, if CONFIGURATION_BUILD_DIR=""; found, remove the line.

• Where's my InputMethod!?!?

  • Check English section. You would found it.

Reference

Thanks to authors!!

• https://mzp.hatenablog.com/entry/2017/09/17/220320
• https://www.logcg.com/en/archives/2078.html
• https://stackoverflow.com/questions/27813151/how-to-develop-a-simple-input-method-for-mac-os-x-in-swift