ios - Segue Methods and Their Objectives -


when press button, want initiate new view controller , want pass information new view controller. handled without segue methods using global variables.

however, if use segue method, 1 of them have use ?

performsegue() or shouldperformsegue()

you have call 

func performsegue(withidentifier identifier: string,             sender: any?)

the above method initiate segue , can push next view controller.

for info

func shouldperformsegue(withidentifier identifier: string,                   sender: any?) -> bool

the method return boolean value, specify if perform segue or not. have controller on , can allow segue perform or not return true/false method.

true - segue allowed , performed

false - segue not allowed , aborted.

you can use method if want override segue have defined in storyboard , want perform other @ run time.


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