Simple "Hello World" extension

Choose Help > Show Extensions Folder, save this file as extensions/user/HelloWorld/main.js, then restart Brackets to see it in effect.

/*jslint vars: true, plusplus: true, devel: true, nomen: true, regexp: true, indent: 4, maxerr: 50 */
/*global define, $, brackets, window */

/** Simple extension that adds a "File > Hello World" menu item */
define(function (require, exports, module) {
    "use strict";

    var CommandManager = brackets.getModule("command/CommandManager"),
        Menus          = brackets.getModule("command/Menus");

    
    // Function to run when the menu item is clicked
    function handleHelloWorld() {
        window.alert("Hello, world!");
    }
    
    
    // First, register a command - a UI-less object associating an id to a handler
    var MY_COMMAND_ID = "helloworld.sayhello";   // package-style naming to avoid collisions
    CommandManager.register("Hello World", MY_COMMAND_ID, handleHelloWorld);

    // Then create a menu item bound to the command
    // The label of the menu item is the name we gave the command (see above)
    var menu = Menus.getMenu(Menus.AppMenuBar.FILE_MENU);
    menu.addMenuItem(MY_COMMAND_ID);
    
    // We could also add a key binding at the same time:
    //menu.addMenuItem(MY_COMMAND_ID, "Ctrl-Alt-H");
    // (Note: "Ctrl" is automatically mapped to "Cmd" on Mac)
});

Looking for more detailed information? Check out How to write extensions, or look up the above APIs in the Brackets source code for complete docs.

---

Here's a slightly fancier version that changes the text in the editor instead of showing an alert() dialog:

/*jslint vars: true, plusplus: true, devel: true, nomen: true, regexp: true, indent: 4, maxerr: 50 */
/*global define, $, brackets */

/** Simple extension that adds a "File > Hello World" menu item. Inserts "Hello, world!" at cursor pos. */
define(function (require, exports, module) {
    "use strict";

    var CommandManager = brackets.getModule("command/CommandManager"),
        EditorManager  = brackets.getModule("editor/EditorManager"),
        Menus          = brackets.getModule("command/Menus");

    
    // Function to run when the menu item is clicked
    function handleHelloWorld() {
        var editor = EditorManager.getFocusedEditor();
        if (editor) {
            var insertionPos = editor.getCursorPos();
            editor.document.replaceRange("Hello, world!", insertionPos);
        }
    }
    
    
    // First, register a command - a UI-less object associating an id to a handler
    var MY_COMMAND_ID = "helloworld.writehello";   // package-style naming to avoid collisions
    CommandManager.register("Hello World 2", MY_COMMAND_ID, handleHelloWorld);

    // Then create a menu item bound to the command
    // The label of the menu item is the name we gave the command (see above)
    var menu = Menus.getMenu(Menus.AppMenuBar.FILE_MENU);
    menu.addMenuItem(MY_COMMAND_ID);
});