diff --git a/src/widget/date/calendar/popup.year.js b/src/widget/date/calendar/popup.year.js
index 39cac5621..7480c9d4d 100644
--- a/src/widget/date/calendar/popup.year.js
+++ b/src/widget/date/calendar/popup.year.js
@@ -70,9 +70,6 @@ BI.YearPopup = BI.inherit(BI.Widget, {
             cardCreator: BI.bind(this._createYearCalendar, this),
             afterCardCreated: function () {
                 this.setValue(self.selectedYear);
-                var calendar = this.getSelectedCard();
-                calendar && self.backBtn.setEnable(self._checkMinYearValid());
-                calendar && self.preBtn.setEnable(self._checkMaxYearValid());
             }
         });
 
@@ -87,22 +84,10 @@ BI.YearPopup = BI.inherit(BI.Widget, {
         }
     },
 
-    _checkMinYearValid: function () {
-        var o = this.options;
-        return this.selectedYear > BI.parseDateTime(o.min, "%Y-%X-%d").getFullYear();
-    },
-
-    _checkMaxYearValid: function () {
-        var o = this.options;
-        return this.selectedYear < BI.parseDateTime(o.max, "%Y-%X-%d").getFullYear();
-    },
-
     _checkMin: function () {
         var calendar = this.navigation.getSelectedCard();
         if (BI.isNotNull(calendar)) {
             calendar.setMinDate(this.options.min);
-            this.backBtn.setEnable(this._checkMinYearValid());
-            this.preBtn.setEnable(this._checkMaxYearValid());
         }
     },
 
@@ -110,8 +95,6 @@ BI.YearPopup = BI.inherit(BI.Widget, {
         var calendar = this.navigation.getSelectedCard();
         if (BI.isNotNull(calendar)) {
             calendar.setMaxDate(this.options.max);
-            this.backBtn.setEnable(this._checkMinYearValid());
-            this.preBtn.setEnable(this._checkMaxYearValid());
         }
     },
 
diff --git a/typescript/index.ts b/typescript/index.ts
index dfc63d328..6d968018e 100644
--- a/typescript/index.ts
+++ b/typescript/index.ts
@@ -148,6 +148,7 @@ import { _utils } from './core/utils';
 import { Controller } from "./core/controller/controller";
 import { LayerController } from "./core/controller/controller.layer";
 import { DateCalendarPopup } from "./widget/date/calendar/popup.calendar.date";
+import { Tree, Node } from "./core/utils/tree";
 
 
 export interface BI extends _func, _i18n, _base, _inject, _var, _web, _utils {
@@ -456,4 +457,6 @@ export {
     FloatCenterLayout,
     DynamicYearMonthPopup,
     DateCalendarPopup,
+    Tree,
+    Node,
 };