Passing Data Between View

ViewA

view 切換前會呼叫 prepareForSegue,
segue 物件同時包含開始及結束兩個 view controllers,
記得幫 Storyboard Segue Identifier 命名 gotoViewB

ViewAController.m
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
  if ([[segue identifier] isEqualToString:@"gotoViewB"]) {
    id vc = segue.destinationViewController;
    [vc setValue:@"hello world 大家好" forKey:@"dataString"];
  }
}

ViewB

在 viewDidLoad 即可取到值。

ViewBController.h
@property (strong) NSString *dataString;
ViewBController.m
- (void)viewDidLoad {
  [super viewDidLoad];
  NSLog(@"output:%@", self.dataString);
  //output:hello world 大家好
}