add

bi/base.js

@@ -1078,10 +1078,9 @@ BI.ButtonGroup = BI.inherit(BI.Widget, {
     //如果是一个简单的layout
     _isSimpleLayout: function () {
         var o = this.options;
-        return o.layouts.length === 1
+        return o.layouts.length === 1 && !BI.isArray(o.items[0])
     },
 
-
     doBehavior: function () {
         var args = Array.prototype.slice.call(arguments);
         args.unshift(this.buttons);

dist/base.js

@@ -1078,10 +1078,9 @@ BI.ButtonGroup = BI.inherit(BI.Widget, {
     //如果是一个简单的layout
     _isSimpleLayout: function () {
         var o = this.options;
-        return o.layouts.length === 1
+        return o.layouts.length === 1 && !BI.isArray(o.items[0])
     },
 
-
     doBehavior: function () {
         var args = Array.prototype.slice.call(arguments);
         args.unshift(this.buttons);

src/base/combination/group.button.js

@@ -115,10 +115,9 @@ BI.ButtonGroup = BI.inherit(BI.Widget, {
     //如果是一个简单的layout
     _isSimpleLayout: function () {
         var o = this.options;
-        return o.layouts.length === 1
+        return o.layouts.length === 1 && !BI.isArray(o.items[0])
     },
 
-
     doBehavior: function () {
         var args = Array.prototype.slice.call(arguments);
         args.unshift(this.buttons);