block传值

B页面

typedef void (^ReturnTextBlock)(NSString *showText);

@interface SelectReasonViewController : UIViewController

@property (weak, nonatomic) IBOutlet UIButton *btn1;

@property (weak, nonatomic) IBOutlet UIButton *btn2;

@property (weak, nonatomic) IBOutlet UIButton *btn3;

@property (weak, nonatomic) IBOutlet UIButton *btn4;

@property (nonatomic, copy) ReturnTextBlock returnTextBlock;

- (void)returnText:(ReturnTextBlock)block;

@end

.m

- (void)returnText:(ReturnTextBlock)block {

    self.returnTextBlock = block;

}

- (IBAction)btn1Action:(id)sender{

    self.returnTextBlock(@"缺货");

    [self.navigationController popViewControllerAnimated:YES];

}

A页面

//选择退款理由

- (IBAction)selectReasonAction:(id)sender {

    SelectReasonViewController *select = [[SelectReasonViewController alloc] init];

    [select returnText:^(NSString *showText) {

        [self.selectResonBtn setTitle:showText forState:UIControlStateNormal];

    }];

    [self.navigationController pushViewController:select animated:YES];

    

}