kero/src/events.js

/**
 * Module : kero DataTable events
 * Author : liuyk(liuyk@yonyou.com)
 * Date   : 2016-07-30 14:34:01
 */


/**
 * 为DataTable对象添加监听
 * @memberof DataTable
 * @param  {string|array|object}   name     针对不同用法分别对应监听名称、监听名称对应的数组、监听名称及对应的回调组成的对象
 * @param  {function} [callback] 监听对应的回调函数
 * @param  {boolean}   [one]      是否只执行一次监听，为true则表示只执行一次回调函数，否则每次触发监听都是执行回调函数
 * @return {DataTable}            当前的DataTable对象
 * @example
 * datatable.on(u.DataTable.ON_ROW_FOCUS, function() {}) // 普通
 * datatable.on([u.DataTable.ON_INSERT, u.DataTable.ON_DELETE], function() {}) // 数组
 * datatable.on({u.DataTable.ON_INSERT: function() {}, u.DataTable.ON_DELETE: function() {}}) // map
 */
const on = function(name, callback, one) {
    var self = this,
        origCb = callback;
    if (Object.prototype.toString.call(name) == '[object Array]') {
        // 数组
        for (var i in name) {
            this.on(name[i], callback);
        }
        return this;
    } else if (typeof name == 'object') {
        // map
        for (var key in name) {
            this.on(key, name[key]);
        }
        return this;
    }
    if (one) {
        callback = function() {
            self.off(name, callback);
            origCb.apply(this, arguments);
        }
    }
    name = name.toLowerCase();
    this._events || (this._events = {});
    var events = this._events[name] || (this._events[name] = []);
    events.push({
        callback: callback
    })
    return this;
}

/**
 * 为DataTable对象取消监听
 * @memberof DataTable
 * @param  {string|array|object}   name     针对不同用法分别对应监听名称、监听名称对应的数组、监听名称及对应的回调组成的对象
 * @param  {function} [callback] 监听对应的回调函数
 * @return {DataTable}            当前的DataTable对象
 * @example
 * datatable.off(u.DataTable.ON_ROW_FOCUS, function() {}) // 普通
 * datatable.off([u.DataTable.ON_INSERT, u.DataTable.ON_DELETE], function() {}) // 数组
 * datatable.off({u.DataTable.ON_INSERT: function() {}, u.DataTable.ON_DELETE: function() {}}) // map
 */
const off = function(name, callback) {
    name = name.toLowerCase();
    if (!this._events)
        return this;
    if (Object.prototype.toString.call(name) == '[object Array]') {
        // 数组
        for (var i in name) {
            this.off(name[i], callback);
        }
        return this;
    } else if (typeof name == 'object') {
        // map
        for (var key in name) {
            this.off(key, name[key]);
        }
        return this;
    }
    var cbs = this._events[name];
    if (!cbs) return this;
    if (!callback) {
        // 解绑所有事件
        cbs = null;
    } else {
        for (var i = cbs.length - 1; i >= 0; i--) {
            if (cbs[i] == callback) {
                cbs.splice(i, 1);
            }
        }
    }
    this._events[name] = cbs;
    return this;
}

/**
 * 为DataTable对象添加只执行一次的监听
 * @memberof DataTable
 * @param  {string|array|object}   name     针对不同用法分别对应监听名称、监听名称对应的数组、监听名称及对应的回调组成的对象
 * @param  {function} [callback] 监听对应的回调函数
 * @example
 * datatable.one(u.DataTable.ON_ROW_FOCUS, function() {}) // 普通
 * datatable.one([u.DataTable.ON_INSERT, u.DataTable.ON_DELETE], function() {}) // 数组
 * datatable.one({u.DataTable.ON_INSERT: function() {}, u.DataTable.ON_DELETE: function() {}}) // map
 */
const one = function(name, callback) {
    this.on(name, callback, 1);
}

/**
 * 触发DataTable对象绑定的事件监听
 * @memberof DataTable
 * @param  {string} name 需要触发的事件监听对应的名称
 * @return {DataTable}            当前的DataTable对象
 * @example
 * datatable.trigger('valuechange')
 */
const trigger = function(name) {
    name = name.toLowerCase()
    if (!this._events || !this._events[name]) return this;
    var args = Array.prototype.slice.call(arguments, 1);
    var events = this._events[name];
    for (var i = 0, count = events.length; i < count; i++) {
        events[i].callback.apply(this, args);
    }
    return this;
}

// 带返回值的trigger，可以获取回调函数的返回值
const triggerReturn = function(name) {
    name = name.toLowerCase()
    if (!this._events || !this._events[name]) return this;
    var args = Array.prototype.slice.call(arguments, 1);
    var events = this._events[name];
    var flag = true;
    for (var i = 0, count = events.length; i < count; i++) {
        flag = flag && events[i].callback.apply(this, args);
    }
    return flag;
}

// 获取监听名称对应的回调函数
const getEvent = function(name) {
    name = name.toLowerCase()
    this._events || (this._events = {})
    return this._events[name]
}

export const eventsFunObj = {
    on: on,
    off: off,
    one: one,
    trigger: trigger,
    triggerReturn: triggerReturn,
    getEvent: getEvent
}