我为我的班级'HotRequest'设置了一个委托,但是在实现它时遇到了问题。我班的代码如下。有任何想法吗?感谢
HotRequest.h
#import <Foundation/Foundation.h>
@protocol HotRequestDelegate;
@interface HotRequest : NSObject {
NSString *requestString;
id <HotRequestDelegate> delegate;
}
@property (nonatomic, retain) NSString *requestString;
@property (nonatomic, assign) id <HotRequestDelegate> delegate;
- (id)initWithRequestOptions:(NSDictionary*)dict;
@end
@protocol HotRequestDelegate <NSObject>
@required
- (void)requestComplete;
@end
HotRequest.m
#import "HotRequest.h"
@implementation HotRequest
@synthesize requestString, delegate;
- (id)initWithRequestOptions:(NSDictionary*)dict {
if ((self = [super init])) {
for (NSString *key in [dict allKeys]) {
requestString = [NSString stringWithFormat:@"%@&%@=%@", requestString, key, [dict objectForKey:key]];
}
NSLog(@"%@", requestString);
}
[delegate requestComplete];
return self;
}
@end
WelcomeViewController.h
#import <UIKit/UIKit.h>
#import "HotRequest.h"
@interface WelcomeViewController : UIViewController <HotRequestDelegate>{
HotRequest *myRequest;
}
@property (nonatomic,retain) HotRequest *myRequest;
@end
WelcomeViewController.m
#import "WelcomeViewController.h"
#import "HotRequest.h"
@implementation WelcomeViewController
@synthesize myRequest;
- (void)viewDidLoad {
[super viewDidLoad];
NSDictionary *mydict = [[NSDictionary alloc] initWithObjectsAndKeys:@"2", @"1", @"4", @"3", nil];
myRequest = [[HotRequest alloc] initWithRequestOptions:mydict];
[[self myRequest] setDelegate:self];
}
- (void)requestComplete {
NSLog(@"request complete");
}
@end
答案 0 :(得分:5)
delegate
中{p> nil
仍为initWithRequestOptions:
。您正在尝试在设置委托之前调用委托方法。