当循环遍历DOM时，我如何检查是否到达了body元素？(when looping through the DOM how do I check if I reached the body element?)

 您可以在执行segue或推送新控制器时将annotation或lat long传递给另一个视图控制器。 如果您正在使用segue，那么您可以使用prepare for segue方法。 
 
 第二件事你可以为mapview制作一个custom class 。 并且可以在其中放置一些属性，如注释或lat long，然后创建此类的对象并设置此属性，以便根据该属性返回地图视图（相应的make方法）。 您可以在许多viewcontroller中使用类，而不仅仅是两个。 
 
 根据评论更新： 
 
 请参阅此链接以了解如何推送新的视图控制器。 并参考这个故事板segue教程 。 实际上它是概念，并且不可能在这里解释一切如果你在代码中有一些错误然后我可以在这里解决但是为了学习整个概念你应该遵循不同的教程和笔记。 做研究。 谷歌你会发现很多链接。 
 
 希望这会有所帮助:) 

you can pass annotation or lat long to another view controller while performing segue or push new controller. If you are using segue then you can use prepare for segue method. 
 
Second thing you can make a custom class for mapview. and can put some properties in it like annotation or lat long then create object of this class and set this property so according that properties this class return map view (make method accordingly). you can use class in many viewcontroller not only in just two.
 
Update as per comment :
 
refer this link to know how to push new view controller. and refer this storyboard segue tutorial. Actually it concepts and not possible to explain here everything if you have some error in code then i can solve here but for learn whole concepts you should follows different tutorials and notes. do research. google it you will find many links.
 
hope this will help :)