'_InternalLinkedHashMap<dynamic, dynamic>' is not a subtype of type 'Map<String, dynamic>'
可以使用new Map<String, dynamic>.from(headers):
Map map = new Map<String, dynamic>.from(headers);
'_InternalLinkedHashMap<dynamic, dynamic>' is not a subtype of type 'Map<String, dynamic>'
可以使用new Map<String, dynamic>.from(headers):
Map map = new Map<String, dynamic>.from(headers);