Passing Data Between View Controllers in iOS: the Definitive Guide (Best Practices + Examples)
I want to pass some information from a child (or destination) view controller to a parent (or source) view controller. The above webpage explains very well how to do the job.
As quoted in the above webpage,
Always use a delegate to communicate information back to other controllers. Your content view controller should never need to know the class of the source view controller or any controllers it doesn’t create.
So I must not create any references of a parent view controller in a child view controller.