Generating Optional Bindings

The GIR bindings generator creates Kotlin/Native bindings for a set of default libraries, but you can also generate bindings for additional libraries by editing the gtkkn.json file.

Editing the gtkkn.json File

The gtkkn.json file configures both the GIR bindings generator and the Gradle project, specifying which libraries to generate bindings for. It also enables additional Gradle modules. Below is an example of the default gtkkn.json file:

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gtkkn.json

{
  "girBaseDir": "/usr/share/gir-1.0",
  "outputDir": "bindings",
  "gradlePluginDir": "gradle-plugin",
  "logLevel": "INFO",
  "skipFormat": false,
  "bindingLicense": "LGPL",
  "libraries": [
    {
      "name": "cairo",
      "module": "core:cairo",
      "girPrefix": "cairo-"
    },
    {
      "name": "gdkpixbuf",
      "module": "core:gdkpixbuf",
      "girPrefix": "GdkPixbuf-"
    },
    {
      "name": "gio",
      "module": "core:gio",
      "girPrefix": "Gio-"
    },
    {
      "name": "glib",
      "module": "core:glib",
      "girPrefix": "GLib-"
    },
    {
      "name": "gmodule",
      "module": "core:gmodule",
      "girPrefix": "GModule-"
    },
    {
      "name": "gobject",
      "module": "core:gobject",
      "girPrefix": "GObject-"
    },
    {
      "name": "graphene",
      "module": "core:graphene",
      "girPrefix": "Graphene-"
    },
    {
      "name": "pango",
      "module": "core:pango",
      "girPrefix": "Pango-"
    },
    {
      "name": "pangocairo",
      "module": "core:pangocairo",
      "girPrefix": "PangoCairo-"
    },
    {
      "name": "gdk",
      "module": "gtk:gdk4",
      "girPrefix": "Gdk-4"
    },
    {
      "name": "gsk",
      "module": "gtk:gsk4",
      "girPrefix": "Gsk-"
    },
    {
      "name": "gtk",
      "module": "gtk:gtk4",
      "girPrefix": "Gtk-4"
    },
    {
      "name": "adw",
      "module": "adwaita",
      "girPrefix": "Adw-1"
    }
  ],
  "ignoredLibraries": [
    {
      "name": "gtksource",
      "module": "extra:gtksource",
      "girPrefix": "GtkSource-5"
    },
    {
      "name": "javascriptcore",
      "module": "extra:javascriptcore",
      "girPrefix": "JavaScriptCore-6.0"
    },
    {
      "name": "soup",
      "module": "extra:soup",
      "girPrefix": "Soup-3.0"
    },
    {
      "name": "webkit",
      "module": "extra:webkit",
      "girPrefix": "WebKit-6.0"
    }
  ]
}

Key Fields in gtkkn.json

• libraries: Lists libraries for binding generation, with metadata:

  • name: The library name (e.g., glib).
  • module: The associated Gradle module, generated in outputDir (e.g., core:glib).
  • girPrefix: The library’s GIR file prefix (e.g., GLib-).

• ignoredLibraries: Lists optional libraries supported by the generator but not generated by default. To enable an optional library, move it from ignoredLibraries to libraries.

Using a Custom Configuration File

To use a custom configuration file instead of the default gtkkn.json, set a Gradle property, org.gtkkn.configFile, with the path to your file. This can be done via the command line or in your ~/.gradle/gradle.properties file.

Command-Line Method

To use a custom configuration file at /path/to/my/config.json, run:

./gradlew gir:run -Dorg.gtkkn.configFile=/path/to/my/config.json

Permanent Method

To make this setting permanent, add it to your ~/.gradle/gradle.properties:

org.gtkkn.configFile=/path/to/my/config.json