Xcode 4.2的编译错误[关闭]

Question

好的，我想我正式发疯了...尝试使用 iOS 5.0 模拟器在 xcode 4.2 上运行此代码并遇到各种错误。在这个应用程序中，我要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

我在“@synthesize locMgr, delegate;”的 .m 文件中遇到错误即“分配属性 'delegate' 的现有 ivar 'delegate' 必须是 _unsafe_unretained”

Answer 1

你不应该assign你的代表，而是应该这样做

 @property (nonatomic, retain) id delegate;

这应该可以解决您的问题。