ios 拖拽环信demo的部分类 到工程 报错

我用的是cocoapods  安装完成了环信的SDK 然后把类拖到工程 就报错了  
 



Undefined symbols for architecture x86_64:

  "_OBJC_CLASS_$_EMChatImage", referenced from:

      objc-class-ref in ChatSendHelper.o

     (maybe you meant: _OBJC_CLASS_$_EMChatImageBubbleView)

  "_OBJC_CLASS_$_EMChatLocation", referenced from:

      objc-class-ref in ChatSendHelper.o

     (maybe you meant: _OBJC_CLASS_$_EMChatLocationBubbleView)

  "_OBJC_CLASS_$_EMChatText", referenced from:

      objc-class-ref in ChatSendHelper.o

     (maybe you meant: _OBJC_CLASS_$_EMChatTextBubbleView)

  "_OBJC_CLASS_$_EMImageMessageBody", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EMLocationMessageBody", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EMMessage", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EMTextMessageBody", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EMVideoMessageBody", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EMVoiceMessageBody", referenced from:

      objc-class-ref in ChatSendHelper.o

  "_OBJC_CLASS_$_EaseMob", referenced from:

      objc-class-ref in ChatSendHelper.o

      objc-class-ref in ChatListViewController.o

      objc-class-ref in AppDelegate+EaseMob.o

      objc-class-ref in MessageModelManager.o

      objc-class-ref in ChatViewController.o

ld: symbol(s) not found for architecture x86_64

clang: error: linker command failed with exit code 1 (use -v to see invocation)