在需要传值的视图接口 声明一个代理 delegate
PushViewController.h中代码
@protocol PushViewControllerDelegate ;
@interface PushViewController : UIViewController
@property (weak, nonatomic) IBOutlet UITextView *pushTextView;
@property (nonatomic,weak) id <PushViewControllerDelegate>delegate;
@end
@protocol PushViewControllerDelegate
-(NSString *)sendValue:(NSString *)message;
@end
//:为什么不写在接口上面呢？ 这样会暴露 内部方法;所以要在上面声明一下这个协议
PushViewController.m代码
- (void)viewDidLoad {
[super viewDidLoad];
_pushTextView.text = [_delegate sendValue:nil];
// Do any additional setup after loading the view.
}
//:视图消失的时候将值传过去
-(void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
_pushTextView.text = [_delegate sendValue:_pushTextView.text];
}
ViewController.h中要实现该代理
ViewController.m文件中
-(NSString *)sendValue:(NSString *)message {
_textView.text = message;
return _textView.text;
}
再prepareForSegue 跟PushViewController进行连线，表明是从PushViewController那边取值
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
PushViewController *pushViewController = segue.destinationViewController;
pushViewController.delegate = self;
}
