Swift gain so much popularity in very short duration and people are really very excited to develop the application in swift. So, the number of application in swift is increasing exponentially. However, there are vast numbers of legacy applications which are built using objective-c and now in the process of migration or mixture (Objective-C & Swift). Today, I will explain how to integrate swift in the existing Objective-c application and vice versa. Let suppose you are working on an application written totally in objective-c and now you want to implement all the new feature in swift then you can follow the following steps to use both the languages in a single application: Access Swift Class into Objective-C 1) Add a new swift file in your application by selecting File -> New->File. Then select a swift file as an option. 2) As you click on "Create", a dialogue box will appear which give you an option to create a bridging Header....