老實念佛，以戒為師

Take notes of self...(xcode9.2, swift4.0)

Step1.  Delete the storyboard

Step2. Target's options > General > Deployment Info > Clear this field("Main") in the Main Interface.

Step3. Open AppDelefate.swift > didFinishLaunchingWithOptions fun：

Remove some other unwanted application delegate methods, leaving only the application:didFinishLaunchingWithOptions that will be called when opened.

Step4. Create the window

Step5. Add Root View Controller and to show