#

API Docs for: 3.10.3
Show: Inherited Protected Private Deprecated

# File: event/js/key.js

    /**
     * Functionality to listen for one or more specific key combinations.
     * @module event
     * @submodule event-key
     */

    var ALT      = "+alt",
        CTRL     = "+ctrl",
        META     = "+meta",
        SHIFT    = "+shift",

        trim     = Y.Lang.trim,

        eventDef = {
            KEY_MAP: {
                enter    : 13,
                esc      : 27,
                backspace: 8,
                tab      : 9,
                pageup   : 33,
                pagedown : 34
            },

            _typeRE: /^(up|down|press):/,
            _keysRE: /^(?:up|down|press):|\+(alt|ctrl|meta|shift)/g,

            processArgs: function (args) {
                var spec = args.splice(3,1)[0],
                    mods = Y.Array.hash(spec.match(/\+(?:alt|ctrl|meta|shift)\b/g) || []),
                    config = {
                        type: this._typeRE.test(spec) ? RegExp.$1 : null,
                        mods: mods,
                        keys: null
                    },
                    // strip type and modifiers from spec, leaving only keyCodes
                    bits = spec.replace(this._keysRE, ''),
                    chr, uc, lc, i;

                if (bits) {
                    bits = bits.split(',');

                    config.keys = {};

                    // FIXME: need to support '65,esc' => keypress, keydown
                    for (i = bits.length - 1; i >= 0; --i) {
                        chr = trim(bits[i]);

                        // catch sloppy filters, trailing commas, etc 'a,,'
                        if (!chr) {
                            continue;
                        }

                        // non-numerics are single characters or key names
                        if (+chr == chr) {
                            config.keys[chr] = mods;
                        } else {
                            lc = chr.toLowerCase();

                            if (this.KEY_MAP[lc]) {
                                config.keys[this.KEY_MAP[lc]] = mods;
                                // FIXME: '65,enter' defaults keydown for both
                                if (!config.type) {
                                    config.type = "down"; // safest
                                }
                            } else {
                                // FIXME: Character mapping only works for keypress
                                // events. Otherwise, it uses String.fromCharCode()
                                // from the keyCode, which is wrong.
                                chr = chr.charAt(0);
                                uc  = chr.toUpperCase();

                                if (mods["+shift"]) {
                                    chr = uc;
                                }

                                // FIXME: stupid assumption that
                                // the keycode of the lower case == the
                                // charCode of the upper case
                                // a (key:65,char:97), A (key:65,char:65)
                                config.keys[chr.charCodeAt(0)] =
                                    (chr === uc) ?
                                        // upper case chars get +shift free
                                        Y.merge(mods, { "+shift": true }) :
                                        mods;
                            }
                        }
                    }
                }

                if (!config.type) {
                    config.type = "press";
                }

                return config;
            },

            on: function (node, sub, notifier, filter) {
                var spec   = sub._extra,
                    type   = "key" + spec.type,
                    keys   = spec.keys,
                    method = (filter) ? "delegate" : "on";

                // Note: without specifying any keyCodes, this becomes a
                // horribly inefficient alias for 'keydown' (et al), but I
                // can't abort this subscription for a simple
                // Y.on('keypress', ...);
                // Please use keyCodes or just subscribe directly to keydown,
                // keyup, or keypress
                sub._detach = node[method](type, function (e) {
                    var key = keys ? keys[e.which] : spec.mods;

                    if (key &&
                        (!key[ALT]   || (key[ALT]   && e.altKey)) &&
                        (!key[CTRL]  || (key[CTRL]  && e.ctrlKey)) &&
                        (!key[META]  || (key[META]  && e.metaKey)) &&
                        (!key[SHIFT] || (key[SHIFT] && e.shiftKey)))
                    {
                        notifier.fire(e);
                    }
                }, filter);
            },

            detach: function (node, sub, notifier) {
                sub._detach.detach();
            }
        };

    eventDef.delegate = eventDef.on;
    eventDef.detachDelegate = eventDef.detach;

    /**
     * <p>Add a key listener.  The listener will only be notified if the
     * keystroke detected meets the supplied specification.  The
     * specification is a string that is defined as:</p>
     *
     * <dl>
     *   <dt>spec</dt>
     *   <dd><code>[{type}:]{code}[,{code}]*</code></dd>
     *   <dt>type</dt>
     *   <dd><code>"down", "up", or "press"</code></dd>
     *   <dt>code</dt>
     *   <dd><code>{keyCode|character|keyName}[+{modifier}]*</code></dd>
     *   <dt>modifier</dt>
     *   <dd><code>"shift", "ctrl", "alt", or "meta"</code></dd>
     *   <dt>keyName</dt>
     *   <dd><code>"enter", "backspace", "esc", "tab", "pageup", or "pagedown"</code></dd>
     * </dl>
     *
     * <p>Examples:</p>
     * <ul>
     *   <li><code>Y.on("key", callback, "press:12,65+shift+ctrl", "#my-input");</code></li>
     *   <li><code>Y.delegate("key", preventSubmit, "#forms", "enter", "input[type=text]");</code></li>
     *   <li><code>Y.one("doc").on("key", viNav, "j,k,l,;");</code></li>
     * </ul>
     *
     * @event key
     * @for YUI
     * @param type {string} 'key'
     * @param fn {function} the function to execute
     * @param id {string|HTMLElement|collection} the element(s) to bind
     * @param spec {string} the keyCode and modifier specification
     * @param o optional context object
     * @param args 0..n additional arguments to provide to the listener.
     * @return {Event.Handle} the detach handle
     */
    Y.Event.define('key', eventDef, true);