xUI.dialog.addButton(.....)ajax没有返回成功原因

例如：

在流程模板管理页面点击新增按钮，弹出编辑页面：

                //编辑流程模板
                editFlowModel: function (modelID) {
                    var that = modObj;
                    var title = "编辑流程模板";
                    var op = "edit";
                    //设置要传递的数据
                    xUI.dialog.setParam({
                        modelID: modelID,
                        op: op
                    });
                    //显示编辑窗体
                    xUI.dialog.open('ModelEdit.html', title, 400, 300);
                },       

 在编辑页面接收传递过来的参数：

                /*初始化组件*/
                initUI: function () {
                    var that = this;
                    //获取页面级别的参数
                    var arg = xUI.dialog.getParam();                    
                    if (arg != undefined) {
                        that.dataStore.modelID = arg.modelID;
                        that.dataStore.op = arg.op;
                        if (arg.modelClassCode != undefined && arg.modelClassCode!="root") {
                            that.dataStore.modelClassCode = arg.modelClassCode;
                        }
                    }

 为编辑页面添加保存按钮：

                /*初始化事件*/
                initEvent: function () {
                    var that = this;
                    //绑定保存按钮
                    xUI.dialog.addButton("保存", function () { return that.saveFlowModel(); }, true, true);                                     
                },

 保存按钮事件：

                //保存流程模板
                saveFlowModel: function () {
                    var that = modObj;
                    var modelName = that.uiStore.txtModelName.getText();
                    if (modelName == "")
                    {
                        alert("模板名称不能为空");
                        return false;
                    }
                    var begDate = that.uiStore.dtbBegDate.getText();                    
                    var endDate = that.uiStore.dtbEndDate.getText();
                    if ( endDate !="" && begDate > endDate )
                    {
                        alert("有效终止日期不能小于有效起始日期");
                        that.uiStore.dtbEndDate.setText("");
                        return false;
                    }                    
                    //保存流程模板
                    var param = {
                        reqType: "SaveFlowModel",
                        modelID: that.dataStore.modelID,
                        modelClassCode: that.uiStore.cmbModelClassName.getValue(),
                        modelName: modelName,
                        modelDesc: that.uiStore.txtModelDesc.getText(),
                        modelBody: that.uiStore.txtModelBody.getText(),
                        begDate: begDate,
                        endDate: endDate,
                        enableFlag: that.uiStore.cmbEnableFlag.getValue()                                       
                    };                   
                    that.ajaxDeal(that.dataStore.ajaxUrl, param, function (result) {                      
                        if (result.state == "ok") {
                            alert("保存成功");
                            xUI.dialog.close();
                            var modelClassCode = "root";
                            xUI.dialog.getParentWin().modObj.loadModelListByClass(modelClassCode);                          
                        }
                        else {
                            alert("保存失败");
                        }
                    });
                    return false;
                } 

 return false;一定要写，否则ajax执行不了成功的回调函数。。。