ios - Best way to perform a task before ViewController change -


what's best way execute given block globally @ phases of uiviewcontroller, in particular, before view controller hidden view (dismissed, view controller pushed, etc.)?

just override builtin notifications: 

- (void)viewwilldisappear:(bool)animated {   [super viewwilldisappear:animated];    // need  }

also see other notifications: 

– viewwillappear: – viewdidappear: – viewwilldisappear: – viewdiddisappear: – viewwilllayoutsubviews – viewdidlayoutsubviews

update: if need uiviewcontrollers in app, have these choices

  1. create custom class , have of viewcontrollers inherit custom class
  2. method swizzling (similar example here)

subclassing best, if impractical reason method swizzling.


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