jQuery 插件开发——PopupLayer(弹出层)

　　导读：上次写了一篇关于GridView的插件开发方法，上几天因为工做须要，花了一天左右的事件封装了popupLayer（弹出层）插件。今天有时间就记录一下本身的开发思想与你们分享下，同时也算是对这段时间的工做概要吧。

　　就我在开发过程当中的理解和开发的经验，通常经常使用的弹出层有三类（其实还有一类就是弹出能够输入内容的，可是这种能够被替代，因此就特别拿出来写了）：Confirm、Alert、LoadContent（url）。其中Alert又能够分红五种（固然也能够是四种），分别是： "error"、"info"、"question"、"warning"、"alert" 。对于每一个名词我就不一一介绍了，相信你们对这几个名词也都不陌生。若是实在了解，能够看下easy ui中的说明。由于不少弹出插件就是相似这样的命名，这样既为了便于他人理解，也便于和主流相一致吧(算是一种“规范”命名吧)。

　　也扯不少了，下面开始真正的开发环节：

　　仍是我上次说过的，开发插件首先要对这个插件有必定的了解。知道它须要什么样的功能，是用来作什么的。这也算是“需求分析”吧。虽然弹出层算是你们得常识吧，也要对其中的做用在进行一次逻辑分析。分析的好处在于你能够提炼这些弹出层的异同点。说到这里我想你们都了解了这是为何了，对，就是要将共同点封装起来。

　　这几个弹出层的共同点不少，例如：弹出的样式、弹出的位置、弹出的方式等等。。。这些均可以封装起来。固然他们的不一样点也很容易看出来，例如：加载的按钮可能不同（Alert通常只有肯定按钮，Confirm通常都是两个按钮，也能够是一个）、警告的图标不一样等等。。。这些都是不一样的地方。固然不一样时相对的。咱们也是能够进一个提炼的。

　　先说下开发步骤吧：

　　第一步：“需求分析”，也就是我上面说的那些。肯定各类弹出层的异同点。

　　第二步：封装共同点

　　第三步：特殊处理，也就是不一样点的处理。（建议写代码的时候分开点，不要全部逻辑都写到一块儿）

　　第四步：整合代码，实现功能。（就是经过本身封装的东西，得到想要的效果）

　　第五步：扩展性问题。这个是我最想强调的。不少人开发的眼光太太短浅（这里不是特指谁，由于我之前也常犯这种问题），开发的插件（或是写的代码），不具备重用性。例如我开发这个的时候就出现了，插件开发完成了，单个测试都很好，没问题。可是同时（或前后）弹出多个层就出问题了，这就是由于当时写代码时候，把一些变量写的太死，致使不能够扩展了。同时弹出来那个层的ID相同了。。。。。。这样悲剧的事情想必不少人都会遇到，之前也用过私人写的第三方插件出现相似的问题。其实出现这样问题归根究底仍是需求分析没作好。

　　第六步：测试。测试时很重要的环节，不少错误状况都是测试出来的。因此不要吝惜那点测试的时间。好的插件（代码）是测出来的。

　　因为篇幅受限只能贴出部分代码以下：

(function () {

    //说明：alert弹出 五种状态 "error"、"info"、"question"、"warning"、"alert"
    var popupEnumType = {
        Error: 1,
        Info: 2,
        Question: 3,
        Warning: 4,
        Alert: 5
    };

    //说明：显示button的类型
    var popupEnumBtn = {
        SureAndCancel: 1,
        SureOnly: 2,
        CancelOnly: 3
    };

    var popupCommon = {
        //获取 Confirm 基础元素
        getBasicElements_Confirm: function (content, isShowIcon) {
            var htmlStr = "";
            htmlStr += "<div class='cancel_dingdai_tixing'> <dl class='f-oh'>";
            if (isShowIcon) {
                htmlStr += "<dd class='f-fl infoIcon'></dd>";
            }
            htmlStr += "<dd class='f-fl cancel_dingdai_text cancel_dingdai_text_content'>" + content + "</dd>" +
                       "     </dl>" +
                       " </div>";
            return htmlStr;
        },

        //获取 Alert 基础元素
        getBasicElements_Alert: function (popupType, content) {           
            var htmlStr = "";
            htmlStr += "<div class='cancel_dingdai_tixing'> <dl class='f-oh'>";
            htmlStr += "<dd class='f-fl ";
            switch (popupType) {
                case popupEnumType.Error:
                    htmlStr += "errorIcon";
                    break;
                case popupEnumType.Info:
                    htmlStr += "infoIcon";
                    break;
                case popupEnumType.Question:
                    htmlStr += "questionIcon";
                    break;
                case popupEnumType.Warning:
                    htmlStr += "warningIcon";
                    break;
                case popupEnumType.Alert:
                    htmlStr += "";
                    break;
            }
            htmlStr += "'></dd>";
            htmlStr += "         <dd class='f-fl cancel_dingdai_text cancel_dingdai_text_content'>" + content + "</dd>" +
                       "     </dl>" +
                       " </div>";
            return htmlStr;
        },

        //得到要显示的弹出层
        getPopupLayerHtml: function (title, boxstyle, contentHtml, popupBtnType, btnSureText, btnCancelText) {

            var htmlStr = "";
            htmlStr += "<div id='" + this.returnId("popupBg") + "' userDefinedAttr='popupLayerBg' class='popupBg'

　　　　　　　　　　  style='z-index:" + this.returnPopupBgZIndex() + "' ></div>";
            htmlStr +=  "<div id='" + this.returnId("popupShow") + "' class='popupShow' "+

　　　　　　　　　　  "   style='z-index:" + this.returnPopupShowZIndex() + "'>" +
                       　　"   <div class='cancel_dingdai_pop'>" +
　　                       "       <div class='cancel_dingdai_wrap_out' id='" + this.returnId("wrapOut") + "'>" +
　　                       "           <div id='popupBox' class='cancel_dingdai_wrap " + boxstyle + "' >" +
      　　                 "               <h2 class='cancel_dingdai_title f-oh'>" +
      　　                 "                   <span class='cancel_dingdai_text f-fl'>" + title + "</span>" +
      　　                 "                   <em id='" + this.returnId("cancelImg") + "' class='cancel_dingdai_title_icon f-fr'>"+

　　　　　　　　　　  "　　　　　　   </em>" +
      　　                 "               </h2>" +
      　　                 "               <div id='" + this.returnId("popupContent") + "' style='width:100%;height:auto;"+

　　　　　　　　　　  "　　　　　　    　　background-color:white'>";
            htmlStr += 　　　　　　　　contentHtml;
            htmlStr += "               </div>";
            htmlStr +=  　　　　　this.getPopupLayerBtn(popupBtnType, btnSureText, btnCancelText);
            htmlStr += "           </div>" +
            　　           "       </div>" +
                  　　     "    </div>" +
                  　　     "</div>";
            return htmlStr;
        },
        //弹出层按钮选择
        getPopupLayerBtn: function (popupBtnType, btnSureText, btnCancelText) {
            btnSureText = this.getParam(btnSureText) == "" ? "肯定" : btnSureText;
            btnCancelText = this.getParam(btnCancelText) == "" ? "取消" : btnCancelText;
            var htmlStr = "";
            htmlStr += "<div class='cancel_dingdai_tijiao'>" +
　　                        "    <dl class='f-fr f-oh'>";
            var sureBtnStr = "<dd class='f-fl cancel_dingdai_submit'>" +
                             "    <input type='button' id='" + this.returnId("popupBtnSure") +

　　　　　　　　　　 "　　'  value='" + btnSureText + "' />" +
                             "</dd>";
            var cancelBtnStr = "<dd class='f-fl cancel_dingdai_cancel'>" +
                             "    <input type='button' id='" + this.returnId("popupBtnCancel") +

　　　　　　　　　　 "　　' value='" + btnCancelText + "' />" +
                             "</dd>";
            switch (popupBtnType) {
                case popupEnumBtn.SureAndCancel:
                    htmlStr += sureBtnStr + cancelBtnStr;
                    break;
                case popupEnumBtn.SureOnly:
                    htmlStr += sureBtnStr;
                    break;
                case popupEnumBtn.CancelOnly:
                    htmlStr += cancelBtnStr;
                    break;
            }

            htmlStr += "    </dl>" +
                        　　"</div>";
            return htmlStr;
        },
        //判断元素是否存在，存在后部分加1
        returnId: function (prefix) {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            if (len < 0) {
                return prefix + "_1";
            }
            len++;
            return prefix + "_" + len;
        },
        returnPopupBgZIndex: function () {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            if (len < 0) {
                return 1001;
            }
            return 1002 + 2 * len - 1;
        },
        returnPopupShowZIndex: function () {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            if (len < 0) {
                return 1002;
            }
            return 1002 + 2 * len;
        },
        //显示弹出层
        showPopup: function () {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            $("#popupBg_" + len).show();
            $("#popupBg_" + len).css("height", $(document).height());
            $("#popupShow_" + len).show();
        },
        //关闭弹出层
        closePopup: function () {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            $("#popupBg_" + len).hide();
            $("#popupShow_" + len).hide();
            $("#popupBg_" + len).remove();
            $("#popupShow_" + len).remove();
        },
        //注册基础事件
        registerBasicEvent: function () {
            //“X”号图标和取消按钮
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            $("#cancelImg_" + len + ",#popupBtnCancel_" + len).click(function () {
                popupCommon.closePopup();
            });
        },
        getParam: function (param) {
            if (typeof (param) == "undefined") {
                return "";
            } else {
                return param;
            }
        },
        popupLayerPosition: function () {
            var len = $("div[userDefinedAttr='popupLayerBg']").length;
            var objHeight = $("#wrapOut_" + len).height() / 2;
            var topValue = $(window).height() / 2 - objHeight + "px";
            $("#wrapOut_" + len).css("margin-top", topValue);
        },

        coverObject: function (obj1, obj2) {
            var o = this.cloneObject(obj1, false);
            var name;
            for (name in obj2) {
                if (obj2.hasOwnProperty(name)) {
                    o[name] = obj2[name];
                }
            }
            return o;
        },

        cloneObject: function (obj, deep) {
            if (obj === null) {
                return null;
            }
            var con = new obj.constructor();
            var name;
            for (name in obj) {
                if (!deep) {
                    con[name] = obj[name];
                } else {
                    if (typeof (obj[name]) == "object") {
                        con[name] = $.cloneObject(obj[name], deep);
                    } else {
                        con[name] = obj[name];
                    }
                }
            }
            return con;
        }
    };

    /************************(弹出层：加载url)*************************/

    var popupLoad = function () {
        this.defaultParams = {
            //参数定义
            title: "",
            boxstyle: "",
            url: "",
            data: "",
            loadback: $.noop,
            callback: $.noop,//注意：返回值要是true/false的方法
            btnId: "",
            btnSureText: "",
            btnCancelText: ""
        };
        this.options = {};
        this.popupLength = 0;
    };

    popupLoad.prototype = {
        constructor: popupLoad,
        init: function (params) {
            this.options = popupCommon.coverObject(this.defaultParams, params);
            this._init(this.options);
        },

        _init: function (options) {
            var popupLay = popupCommon.getPopupLayerHtml(this.options.title, this.options.boxstyle, "",

　　　　　　　　　　　　popupEnumBtn.SureAndCancel, this.options.btnSureText, this.options.btnCancelText);
            $("body").append(popupLay);
            $("#" + options.btnId).attr("disabled", "disabled");//防止屡次发送请求
            $.ajaxSetup({
                cache: false //关闭 AJAX 缓存
            });
            this.popupLength = $("div[userDefinedAttr='popupLayerBg']").length;
            $("#popupContent_" + this.popupLength).load(options.url, options.data, function () {
                popupCommon.showPopup();
                popupCommon.popupLayerPosition();
                $("#" + options.btnId).removeAttr("disabled");
                if ($.isFunction(options.loadback)) {
                    options.loadback();
                }
            });
            popupCommon.registerBasicEvent();
            this._registerBtnClick(options);
        },
        _registerBtnClick: function (options) {
            var len = this.popupLength;
            $("#popupBtnSure_" + len).click(function () {
                if (!$.isFunction(options.callback)) {
                    return;
                }
                if (!options.callback()) {
                    return;
                }
                popupCommon.closePopup();
            });
        }
    };

    $.popupLoad = new popupLoad();

    /************************(弹出层：confirm框)*************************/

    var popupConfirm = function () {
        //参数定义
        this.defaultParams = {
            //参数定义
            title: "",
            content: "",
            boxstyle: "",
            isShowIcon: true,
            callback: $.noop,//注意：返回值要是true/false的方法
            btnSureText: "",
            btnCancelText: ""
        };
        this.options = {};
        this.popupLength = 0;
    };

    popupConfirm.prototype = {
        constructor: popupConfirm,
        init: function (params) {
            this.options = popupCommon.coverObject(this.defaultParams, params);
            this._init(this.options);
        },
        _init: function (options) {
            var contentHtml = popupCommon.getBasicElements_Confirm(this.options.content, this.options.isShowIcon);
            var popupLay = popupCommon.getPopupLayerHtml(this.options.title, this.options.boxstyle, contentHtml,

　　　　　　　　　　　　  popupEnumBtn.SureAndCancel, this.options.btnSureText, this.options.btnCancelText);
            $("body").append(popupLay);
            this.popupLength = $("div[userDefinedAttr='popupLayerBg']").length;
            popupCommon.showPopup();
            popupCommon.registerBasicEvent();
            popupCommon.popupLayerPosition();
            this._registerBtnClick(options);
        },
        _registerBtnClick: function (options) {
            var len = this.popupLength;
            $("#popupBtnSure_" + len).click(function () {
                popupCommon.closePopup();
                if ($.isFunction(options.callback)) {
                    options.callback();
                }
            });
        }
    };
    $.popupConfirm = new popupConfirm();

    /************************(弹出层：Alert框)*************************/

    var popupAlert = function (popupType) {
        //参数定义
        this.defaultParams = {
            title: "",
            content: "",
            boxstyle: "",
            callback: $.noop,//注意：返回值要是true/false的方法
        };
        this.options = {};
        this.popupLength = 0;
        this.popupType = popupType;
    };
    popupAlert.prototype = {
        constructor: popupAlert,
        init: function (params) {
            this.options = popupCommon.coverObject(this.defaultParams, params);
            this._init(this.options);
        },
        _init: function (options) {
            var contentHtml = popupCommon.getBasicElements_Alert(this.popupType, this.options.content);
            var popupLay = popupCommon.getPopupLayerHtml(this.options.title, this.options.boxstyle,

　　　　　　　　　　　　  contentHtml, popupEnumBtn.SureOnly);
            $("body").append(popupLay);
            this.popupLength = $("div[userDefinedAttr='popupLayerBg']").length;
            popupCommon.showPopup();
            popupCommon.registerBasicEvent();
            popupCommon.popupLayerPosition();
            this._registerBtnClick(options);
        },
        _registerBtnClick: function (options) {
            var len = this.popupLength;
            $("#popupBtnSure_" + len).click(function () {
                popupCommon.closePopup();
                if ($.isFunction(options.callback)) {
                    options.callback();
                }
            });
        }
    };
    $.popupError = new popupAlert(popupEnumType.Error);
    $.popupInfo = new popupAlert(popupEnumType.Info);
    $.popupQuestion = new popupAlert(popupEnumType.Question);
    $.popupWarning = new popupAlert(popupEnumType.Warning);
    $.popupAlert = new popupAlert(popupEnumType.Alert);
})(jQuery);

　　总结：因为篇幅太长css样式就不贴了，若是有须要或者想共同探讨的同仁，随时联系我，QQ:296319075  同时也但愿你们提出宝贵意见，不吝赐教。共同进步！若有转载，请注明出处，谢谢！^_^