objective-c - 前缀属性必须后跟接口或协议栈溢出

Question

[编译器错误] 前缀属性必须后跟接口或协议堆栈溢出代码在上一个中运行良好。项目。发布这么简单的问题，我觉得自己像个白痴。这东西有什么问题？

#import <UIKit/UIKit.h>
#import "FlipsideViewController.h"

@interface MainViewController : UIViewController <FlipsideViewControllerDelegate>
<UIPickerViewDelegate><UIPickerViewDataSource>

@property (strong, nonatomic) IBOutlet UITextField *inputText;
@property(strong, nonatomic) IBOutlet UIPickerView *picker;
@property(strong, nonatomic) IBOutlet UILabel *resultLabel;
@property(strong, nonatomic) NSArray *_convertFrom;
@property(strong, nonatomic) NSArray *_convertTo;
@property(strong, nonatomic) NSArray *_convertRates;
@property(strong, nonatomic) IBOutlet UILabel *formelLabel;
@property(strong, nonatomic) IBOutlet UITextField *inputText;


-(IBAction)textFieldReturn:(id)sender;
-(IBAction)backgroundTouched:(id)sender;


@end

Answer 1

您声明符合多个协议，如下所示：

@interface MainViewController : UIViewController <FlipsideViewControllerDelegate, UIPickerViewDelegate, UIPickerViewDataSource>

不适用于多个尖括号组。