Objective-C的问题与Segue公司

Question

我有这个Segue公司在这里：

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { 
    if ([[segue identifier] isEqualToString:@"showDetail"]) { 
     NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow]; 
     //NSDate *object = self.objects[indexPath.row]; 
     NSString *strPOIndex = [self.tableData[indexPath.row] valueForKey:@"POIndex"]; 
     LHPurchaseOrderDetail *controller = (LHPurchaseOrderDetail *)[[segue destinationViewController] topViewController]; 
     [controller setDetailItem:strPOIndex]; 
     controller.navigationItem.leftBarButtonItem = self.splitViewController.displayModeButtonItem; 
     controller.navigationItem.leftItemsSupplementBackButton = YES; 
    } 
} 

和我试图用它做的是通过strPOIndex从我的主控制器我的详细控制器setDetailItem ..但是当我运行这个，我得到一个错误：

-[LHPurchaseOrderMaster setDetailItem:]: unrecognized selector sent to instance 0x156cce80 

我不明白为什么会发生这种情况，这是我的故事板的问题？或我的主控制器或细节控制器？这里是我的详细信息控制器：

.H：

#import <UIKit/UIKit.h> 

@interface LHPurchaseOrderDetail : UIViewController 

@property (strong, nonatomic) IBOutlet UINavigationBar *NavBar; 
@property (strong, nonatomic) id detailItem; 
@property (weak, nonatomic) IBOutlet UILabel *detailDescriptionLabel; 

@end 

.M：

#import "LHPurchaseOrderDetail.h" 

@interface LHPurchaseOrderDetail() 

@end 

@implementation LHPurchaseOrderDetail 

- (void)setDetailItem:(id)newDetailItem { 
    if (_detailItem != newDetailItem) { 
     _detailItem = newDetailItem; 

     // Update the view. 
     [self configureView]; 
    } 
} 

- (void)configureView { 
    // Update the user interface for the detail item. 
    if (self.detailItem) { 
     self.detailDescriptionLabel.text = [self.detailItem description]; 
    } 
} 


- (void)viewDidLoad { 
    [super viewDidLoad]; 

    [self configureView]; 
} 

- (void)didReceiveMemoryWarning { 
    [super didReceiveMemoryWarning]; 
} 


@end 

主控制器：

.H

#import <UIKit/UIKit.h> 
#import "ShinobiDataSource.h" 
#import "PopupGenerator.h" 

@class LHPurchaseOrderDetail; 

@interface LHPurchaseOrderMaster : UITableViewController<UIPopoverControllerDelegate, UIPickerViewDelegate> 


@property (strong, nonatomic) IBOutlet UIButton *communityBtn; 
@property (strong, nonatomic) IBOutlet UIButton *lotBtn; 
@property (strong, nonatomic) IBOutlet UIButton *goBtn; 


- (IBAction)communityBtnPressed:(id)sender; 
- (IBAction)lotBtnPressed:(id)sender; 
- (IBAction)goBtnPressed:(id)sender; 

@property(nonatomic, retain) NSArray * tableData; 
@property (strong, nonatomic) LHPurchaseOrderDetail *purchaseOrderController; 


@end 

Answer 1

看来，您尝试访问的财产不是交流可接受的（错误的检索对象）。

您是否尝试过使用，而不是

LHPurchaseOrderDetail *controller = (LHPurchaseOrderDetail *)[[segue destinationViewController] topViewController]; 

喜欢的东西

LHPurchaseOrderDetail *controller = (LHPurchaseOrderDetail *)[[segue destinationViewController] viewControllers][0]; 

我有时同您的问题。

Answer 2

将您的detailItem设置为NSString。不是身份证。问题就在这里，

self.detailDescriptionLabel.text = [self.detailItem description]; 

在configureView方法更改代码如下，

- (void)configureView { 
    // Update the user interface for the detail item. 
    if (self.detailItem) { 
     self.detailDescriptionLabel.text = self.detailItem; 
    } 
} 

不要忘记改变这个为好，

- (void)setDetailItem:(NSString *)newDetailItem { 
    if (_detailItem != newDetailItem) { 
     _detailItem = newDetailItem; 

     // Update the view. 
     [self configureView]; 
    } 
} 

Answer 3

你的错误是这样的：

-[LHPurchaseOrderMaster setDetailItem:]: unrecognized selector sent to instance 0x156cce80 

所以看起来你试图访问LHPurchaseOrderMaster类的某个地方，并将detailItem属性设置为LHPurchaseOrderMaster的一部分，但因为它不存在，所以会出现unrecognized selector错误。

编辑

您应该检查三两件事：

1. 在Interface Builder检查，从LHPurchaseOrderMaster的ViewController的SEGUE是一个UINavigationController嵌入了LHPurchaseOrderDetail的ViewController在第一视图控制器其叠加。

2. 检查由[segue destinationViewController]topViewController]这样返回的类名称：

   id obj = [segue destinationViewController]topViewController]; NSLog(@"%@", NSStringFromClass([obj class]));

类的名称应该是LHPurchaseOrderDetail。如果不是这样，那么你的故事板中有一个问题，当然你不是错误地将连线连接起来。

1. 请检查您的LHPurchaseOrderMaster类是否有任何试图访问“detailItem”属性的代码，就好像它是该类的一部分一样。