代表和协议目标c

Question

我在这个论坛上给出了一些建议，我仍然遇到了困难

我有以下内容：

    #import <UIKit/UIKit.h>


    @protocol UIViewForWheelProtocol

    - (void) returnImageNumber:(int)imgNum;

    @end


    #import <UIKit/UIKit.h>
    #import "UIViewForWheelProtocol.h";


    @interface UIViewForWheel : UIView {
        id<UIViewForWheelProtocol> delegate;
    }

    @property (nonatomic, assign) id<UIViewForWheelProtocol> delegate;



    @implementation UIViewForWheel

    @synthesize delegate;

    -(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
       int num =1 ;
       [self.delegate returnImageNumber:num];
    }

#import <UIKit/UIKit.h>
#import "UIViewForWheel.h"
#import "UIViewForWheelProtocol.h"


@interface MainMenu : UIViewController <UIViewForWheelProtocol> {

}

-(void) returnImageNumber:(int)whichImage;

@end


    #import "MainMenu.h"


    @implementation MainMenu

    - (void) returnImageNumber:(int)whichImage
    {
        NSLog(@"HI %i", whichImage);
    }

HI 1未显示，因为虽然它将转到touchesMoved函数，但它不会转到MainMenu类中的returnImageNumber。

有人可以解释一下我做错了吗？

Answer 1

确保您已为UIViewForWheel手动分配了代理，MainMenu符合该协议UIViewForWheelProtocol。