1、空类型判断的完善

lib/util/empty_util.dart

@@ -4,14 +4,14 @@ class EmptyUtil {
   /// 判断是否为空，object的类型可以为：String Map List
   static bool isEmpty(Object object) {
     if (null == object) return true;
-    if (object is String && object.isEmpty) {
+    if (object is String && (object.isEmpty || object.length == 0)) {
       return true;
     }
-    if (object is List && object.isEmpty) {
+    if (object is List && (object.isEmpty || object.length == 0)) {
       return true;
     }
 
-    if (object is Map && object.isEmpty) {
+    if (object is Map && (object.isEmpty || object.length == 0)) {
       return true;
     }
     return false;