编译Xcode 4.2的错误

Question

好吧，我想我正式正在疯狂...尝试在iOS 5.0模拟器上运行xcode 4.2上的此代码并获取各种错误。在这个应用程序中，我试图做的就是运行核心位置API。

我的位置 “控制器” 类：

.H：

#import Foundation/Foundation.h 
#import CoreLocation/CoreLocation.h 

@protocol locationReceiverDelegate 
@required 

- (void)locationUpdate:(CLLocation *)location; 
- (void)locationError:(NSError *)error; 

@end 

@interface locationReceiver : NSObject <CLLocationManagerDelegate> { 
    CLLocationManager *locMgr; 
    id delegate; 
} 

@property (nonatomic, retain) CLLocationManager *locMgr; 
@property (nonatomic, assign) id delegate; 

@end 

.M：

#import "locationReceiver.h" 

@implementation locationReceiver 

@synthesize locMgr, delegate; 


- (id)init 
{ 
    self = [super init]; 
    if(self != nil) { 
     self.locMgr = [[CLLocationManager alloc] init]; 
     self.locMgr.delegate = self; 
    } 

    return self; 
} 

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation  *)newLocation fromLocation:(CLLocation *)oldLocation { 
// if([self.delegate conformsToProtocol:@protocol(locationReceiverDelegate)]) { 
     [self.delegate locationUpdate:newLocation]; 
//  } 
} 

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error { 
// if([self.delegate conformsToProtocol:@protocol(locationReceiverDelegate)]) { 
     [self.delegate locationError:error]; 
// } 
} 


@end 

我得到一个错误的.m文件是“@synthesize locMgr ，代表;“ ，“对于指派属性‘代表’现有伊娃‘代理’必须_unsafe_unretained”

Answer 1

你不应该assign您的委托，而做

@property (nonatomic, retain) id delegate; 

这应该解决您的问题。