keyboard-js

JavaScript Key Binding Library

Version vom 22.09.2016. Aktuellste Version

Dieses Skript sollte nicht direkt installiert werden. Es handelt sich hier um eine Bibliothek für andere Skripte, welche über folgenden Befehl in den Metadaten eines Skriptes eingebunden wird // @require https://updategreasyfork.deno.dev/scripts/23404/148849/keyboard-js.js

"use strict"
var Keyboard = (function () {
    function __Keyboard() {
        this.keys = {} // to record the pressed key
        this.register_list = {} // to record the registers(key combos)
        this.state = {} // to record every register matching condition. do you want to get this value?
        this.specialKeyString = {
            "altKey": "Alt",
            "ctrlKey": "Control",
            "metaKey": "Meta",
            "shiftKey": "Shift"
        }
    }
    __Keyboard.prototype.listen = function () {
        var option = this.option, element = document
        if (option.element && typeof option.element.addEventListener === 'function') {
            element = option.element
        }
        element.addEventListener('keydown', this.keydown.bind(this), false)
        element.addEventListener('keyup', this.keyup.bind(this), false)
    }

    __Keyboard.prototype.unlisten = function () {
        // maybe you need callback?
        var option = this.option, element = document
        if (option.element && typeof option.element.removeEventListener === 'function') {
            element = option.element
        }
        element.removeEventListener('keydown', function () { })
        element.removeEventListener('keyup', function () { })
    }

    __Keyboard.prototype.test = function (event) {
        return this.testRegisters(event)
    }

    __Keyboard.prototype.testRegisters = function (event) {
        var register_list = this.register_list
        var register_names = Object.keys(register_list)
        var testKeys = this.testKeys.bind(this)
        var state = {}
        for (var i = 0, len = register_names.length; i < len; i++) {
            var regName = register_names[i]
            var reg = register_list[regName]
            var keylist = reg[0]
            var callback = reg[1]

            // hit the target
            if (testKeys(keylist)) {
                if (callback && typeof callback === 'function') {
                    // TODO:
                    // Need event object? or context?
                    var __wrapper_callback = (function () {
                        event.clearKeys = this.clearKeys.bind(this)
                        // inject the event(the last key) object
                        callback(event)

                        // BUG:
                        // when use `alert` or `confirm`, the event(keyup) of the pressed key will lost.
                        // so, you will don't know the key is really pressed or not when you are back.
                        // here code just detects some special keys.
                        // SO DO NOT USE ALERT OR CONFIRM!
                        Array.prototype.map.call(Object.keys(this.specialKeyString), ((function (key) {
                            if (event[key]) this.keys[this.specialKeyString[key]] = true
                        }).bind(this)))
                    }).bind(this)

                    if (window.requestAnimationFrame)
                        window.requestAnimationFrame(__wrapper_callback)
                    else
                        setTimeout(__wrapper_callback, 16)
                }
                state[regName] = true
                // if match successfully, return directly.
                return state
            }
        }
        return state
    }

    // @param keylist Array(Array) [combo1, combo2, ...]
    __Keyboard.prototype.testKeys = function (keylist) {
        var result = [], state = false
        for (var i = 0, len = keylist.length; i < len; i++) {
            var combo = keylist[i]
            var allPressedkeys = Object.keys(this.keys)
            var nowPressedkeys = []
            var __state = 0 // no state. not true or false

            // collect all pressed key now
            allPressedkeys.forEach((function (value, index) {
                if (this.keys[value]) nowPressedkeys.push(value)
            }).bind(this))

            // DEBUG: print the pressing key message
            // console.log(allPressedkeys, this.keys)
            if (this.option.DEBUG === true) {
                var __printKey = nowPressedkeys.map(function (k, i) {
                    if (k === " ") return "Space"
                    else return k
                }).join(" ")
                console.log('[' + Date.now() + '] You hit key: %c' + __printKey, 'color: #ea4335; font-size: 16px')
            }

            // compare nowPressedkeys and combo
            // console.log('compare: ', nowPressedkeys, combo)
            if (nowPressedkeys.length !== combo.length) {
                __state = false
            } else {
                for (var j = 0, len2 = combo.length; j < len2; j++) {
                    if (nowPressedkeys.indexOf(combo[j]) < 0) {
                        // not in the array
                        __state = false
                        break
                    }
                }
                // if j is equal to combo.length, this means that user hit the combo.
                // otherwise, user does't.
                if (j === combo.length && __state !== false) __state = true
            }
            result.push(__state)
        }
        // console.log('> result', result, this.keys)
        result.forEach(function (v, i) {
            if (v === true) state = true
        })
        return state
    }

    __Keyboard.prototype.keydown = function (event) {
        var key = event.key, state = {}, rlt = true, map = Array.prototype.map
        this.keys[key] = event.type === 'keydown'
        // this.keys[key] = true
        // the result of test
        // true: hit the target, then prevent the default action, so return true
        // otherwise, don't prevent it, so return false
        state = this.test(event)
        Object.keys(state).forEach(function (regName, i) {
            if (state[regName] === true) rlt = false
        })
        this.state = state
        if (!rlt) {
            event.preventDefault()
            event.stopPropagation()
            // event.stopImmediatePropagation()
        }
        // console.log(rlt)
        return rlt
    }

    __Keyboard.prototype.keyup = function (event) {
        var key = event.key
        this.keys[key] = false
        return true
    }

    __Keyboard.prototype.register = function (name, callback, keylist) {
        if (typeof name !== 'string') throw new Error('Please input the register name.')
        if (this.register_list[name]) throw new Error('The ' + name + ' has existed!')
        var keylist = Array.prototype.slice.call(arguments, 2)
        if (!(keylist[0] instanceof Array)) keylist = [keylist] // init [combo1:Array, combo2:Array, ....]
        this.register_list[name] = [keylist, callback]
    }

    __Keyboard.prototype.clearRegister = function (name) {
        delete this.register_list[name]
    }
    __Keyboard.prototype.clearRegisterAll = function () {
        this.register_list = {}
    }
    __Keyboard.prototype.clearKeys = function () {
        this.keys = {}
    }
    var k = new __Keyboard()

    var __instance = {
        start: function () { k.listen() },
        end: function () { k.unlisten(); k.clearRegisterAll(); k.clearKeys(); },
        register: function () { k.register.apply(k, arguments) },
        unregister: function () { k.clearRegister.apply(k, arguments) },
        // for test
        __keydown: function () { k.keydown.apply(k, arguments) },
        __keyup: function () { k.keyup.apply(k, arguments) },
    }

    return function (o) {
        k.option = o || {}
        window.addEventListener('focus', function () {
            k.keys = {}
        }, false)
        // window.addEventListener('blur', function () {
        //     k.keys = {}
        // }, false)
        return __instance
    }
})()

if (typeof exports !== "undefined") {
    exports.Keyboard = Keyboard
} else if (typeof define !== 'undefined' && typeof define === 'function') {
    define("Keyboard", [], function () {
        return Keyboard
    })
} else {
    if (window.Keyboard === undefined) window.Keyboard = Keyboard
    else {
        throw new Error('Library Keyboard has existed! Loaded failed.')
    }
}