Question

我正在尝试构建一个测试iOS应用来解析来自eBay API的JSON，而我却无法将响应转发给代理。我在ItemCommunicator实现中收到了No known instance method for selector和fetchingItemsFailedWithError方法的警告receivedItemsJSON错误。

XYZItemCommunicator.m：

#import "XYZItemCommunicator.h"
#import "XYZItemCommunicatorDelegate.h"
@implementation XYZItemCommunicator

- (void)searchItems
{
    NSString *urlAsString = [NSString stringWithFormat:@"http://svcs.ebay.com/services/search/FindingService/v1?SECURITY-APPNAME=**************&OPERATION-NAME=findItemsByKeywords&SERVICE-VERSION=1.12.0&RESPONSE-DATA-FORMAT=JSON&callback=_cb_findItemsByKeywords&REST-PAYLOAD&sortOrder=PricePlusShippingLowest&paginationInput.entriesPerPage=7&outputSelector=AspectHistogram&itemFilter(0).name=Condition&itemFilter(0).value(0)=New&itemFilter(1).name=MaxPrice&itemFilter(1).value=450.00&itemFilter(1).paramName=Currency&itemFilter(1).paramValue=USD&itemFilter(2).name=MinPrice&itemFilter(2).value=350.00&itemFilter(2).paramName=Currency&itemFilter(2).paramValue=USD&itemFilter(3).name=ListingType&itemFilter(3).value=FixedPrice&keywords=Moto+x+16gb+unlocked"];
    NSURL *url = [[NSURL alloc] initWithString:urlAsString];
    NSLog(@"%@", urlAsString);

    [NSURLConnection sendAsynchronousRequest:[[NSURLRequest alloc] initWithURL:url] queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {

        if (error) {
            [self.delegate fetchingItemsFailedWithError:error];
        } else {
            [self.delegate receivedItemsJSON:data];
        }
    }];
}

@end

XYZItemCommunicator.h：

#import <Foundation/Foundation.h>

@protocol ItemCommunicatorDelegate;

@interface XYZItemCommunicator : NSObject
@property (weak, nonatomic) id<ItemCommunicatorDelegate> delegate;

@end

XYZItemCommunicatorDelegate.h：

#import <Foundation/Foundation.h>

@protocol XYZItemCommunicatorDelegate <NSObject>
- (void)receivedItemsJSON:(NSData *)objectNotation;
- (void)fetchingItemsFailedWithError:(NSError *)error;
@end

Answer 1

检查您的协议名称。你从

开始

ItemCommunicatorDelegate

并改为

XYZItemCommunicatorDelegate

没有已知的选择器'receivedItemsJSON'的实例方法

1 个答案: