Introduction

From Cocos Creator 3.7.0, we switch the approach of generating JS binding code from bindings-generator to Swig. Swig has many benefits in generating glue code by parsing its custom interface file (IDL) which is compatible with C++. For more about why we switch to Swig, you could refer to this issue .

Generate JS Binding Code for Engine

• Make sure you have installed NodeJS (>= v8.9.4)

• Open Terminal (macOS/Linux) or Command Line Tool (Windows), navigate to engine/native/tools/swig-config

• Run node genbindings.js

• If succeed, you’ll see the text:

  ======================================================================
      Congratulations, JS binding code was generated successfully!
  ======================================================================

• If failed, you need to check the output and figure out whether there’re some errors in .i files.

Generate JS Bindings Code for Developer’s Project

• Make sure you have installed NodeJS (>= v8.9.4)

• Open Terminal (macOS/Linux) or Command Line Tool (Windows)

• Create a directory for generated code, e.g. /Users/abc/my-project/native/engine/common/Classes/bindings/auto

• Write a JS configuration file

  • Create the JS configruation file, e.g. /Users/abc/my-project/tools/swig-config/swig-config.js with the following content

    'use strict';
    const path = require('path');
    // Developer's custom module configuration
    // configList is required
    const configList = [
      [ 'your_module_interface_0.i', 'jsb_your_module_interface_0_auto.cpp' ],
      [ 'your_module_interface_1.i', 'jsb_your_module_interface_1_auto.cpp' ],
      // ......
    ];
    const projectRoot = path.resolve(path.join(__dirname, '..', '..'));
    // interfaceDir is optional
    const interfacesDir = path.join(projectRoot, 'tools', 'swig-config');
    // bindingsOutDir is optional
    const bindingsOutDir = path.join(projectRoot, 'native', 'engine', 'common', 'Classes', 'bindings', 'auto');
    module.exports = {
      interfacesDir, // optional, if it isn't exported, the items in configList should be absolute or relative to current directory of swig-config.js
      bindingsOutDir, // optional, if it isn't exported, the items in configList should be absolute or relative to current directory of swig-config.js
      configList // required
    };

  • Run the following command

    # If current workspace is not in '/Users/abc/my-project/tools/swig-config'
    $ node < Engine Root Path >/native/tools/swig-config/genbindings.js -c /Users/abc/my-project/tools/swig-config/swig-config.js

    # If you have already navigate to '/Users/abc/my-project/tools/swig-config' directory, you could run the command without -c argument like:
    $ cd /Users/abc/my-project/tools/swig-config
    $ node < Engine Root Path >/native/tools/swig-config/genbindings.js

Swig Interface File

• There is a swig-interface-template.i in engine/native/tools/swig-config directory, just copy and rename it to some place in your project. There some comments demonstrate how to configure your module in .i file. You could also reference engine internal .i files in engine/native/tools/swig-config, for instance, scene.i or assets.i for a quick start.
• If you’re using Visual Studio Code, you could install SWIG Language extension which was developed by Hong-She Liang for highlight syntax support.
• For more details of writing .i file, please visit tutorial section.

Tutorial

Visit The Tutorial of Swig Workflow in Cocos Creator, which includes binding a new module in engine or user’s project step by step.