Objective C - IOS - 在类型的对象上找不到属性 - 访问对象变量时

Objective C - IOS - Property not found on object of type - when accessing object variables

提问by Dancer

I'm building a UIView which is connected to a UITableView containing a list of shop items and populated by an array of data which is associated to an object class (shopObjects).

我正在构建一个 UIView，它连接到包含商店项目列表的 UITableView，并由与对象类 (shopObjects) 关联的数据数组填充。

here is my shop objects H file -

这是我的商店对象 H 文件 -

#import <Foundation/Foundation.h>

@interface shopObjects : NSObject



@property(strong) NSString *shopITitle;
@property(strong) NSString *shopIGroup;
@property(strong) NSString *shopIDesc;
@property(strong) NSString *shopIPrice;
@property Boolean offer;


-(id)initWithshopITitle:(NSString *)shopITitleD shopIGroup:(NSString *)shopIGroupD shopIDesc: (NSString *)shopIDescD shopIPrice:(NSString *)shopIPriceD offer:(Boolean )offerD;


@end

Shop Object . M file

商店对象。M档

#import "shopObjects.h"

@implementation shopObjects

-(id)initWithshopITitle:(NSString *)shopITitleD shopIGroup:(NSString *)shopIGroupD shopIDesc:(NSString *)shopIDescD shopIPrice:(NSString *)shopIPriceD offer:(Boolean )offerD{
self= [super init];
if(self){
    self.shopITitle = shopITitleD;
    self.shopIGroup = shopIGroupD;
    self.shopIDesc = shopIDescD;
    self.shopIPrice = shopIPriceD;
    self.offer = (offerD);



}
return self;


}


@end

this is my view controller .h file -

这是我的视图控制器 .h 文件 -

#import <UIKit/UIKit.h>
#import "shopObjects.h"

@interface shopVCSelectionViewController : UIViewController

@property (weak, nonatomic) IBOutlet UIScrollView *shopResScroller;
@property (weak, nonatomic) IBOutlet UILabel *ShopItemTitle;
@property (weak, nonatomic) IBOutlet UITextView *ShopItemDesc;
@property (weak, nonatomic) IBOutlet UILabel *ShopItemPrice;

@end

and VC .m file -

和 VC .m 文件 -

#import "shopVCViewController.h"

@interface shopVCViewController ()

@end

@implementation shopVCViewController



- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization




  }
  return self;
}

- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.

//Set Scroller
[self.shopScroll setScrollEnabled:YES];
[self.shopScroll setContentSize:CGSizeMake(320, 1100)];
 self.title = @"Shop";
 self.shopArray = [NSArray arrayWithObjects:@"1 x PT session - ￡25",@"3 for 2 PT sessions     - ￡50 ",@"1 x Running Club - ￡15",@"1 x PT session",   nil];
}


- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}

- (NSInteger)tableView:(UITableView *)tableView
 numberOfRowsInSection:(NSInteger)section
{
return [self.shopArray count];
}

-(UITableViewCell *)tableView:(UITableView *)tableView
    cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier =@"Cell";
UITableViewCell *cell = [tableView
                         dequeueReusableCellWithIdentifier:CellIdentifier      forIndexPath:indexPath];
cell.textLabel.text=[self.shopArray  objectAtIndex:indexPath.row];

return cell;
}



- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}

@end

I am trying to link up the labels/text fields with the relevant object variables - but the shopObjects object / associated variables dont appear in the predictive text and I get the following property not found error - I've no idea why! Can anyone offer some advice please?

我正在尝试将标签/文本字段与相关对象变量联系起来 - 但 shopObjects 对象/关联变量没有出现在预测文本中，并且我收到以下属性未找到错误 - 我不知道为什么！任何人都可以提供一些建议吗？

采纳答案by Simon McLoughlin

You did not inherit shopObjectsin your viewController. It is a separate object.You need to create a variable of type shopObjects, set its properties and then call that. e.g.

您没有shopObjects在 viewController 中继承。它是一个单独的对象。您需要创建一个 type 变量shopObjects，设置其属性，然后调用它。例如

shopVcSelectionViewController.h

@property (strong, nonatomic) shopObjects *shopObject;




shopVcSelectionViewController.m

...
self.shopItemTitle.text = self.shopObject.shopTitle
...

回答by Duncan C

The code you posted is in an instance method of the class shopSelectionViewController. A shopSelectionViewController has a property shopItemTitle, but not a shopITitle property.

您发布的代码位于类 shopSelectionViewController 的实例方法中。shopSelectionViewController 有一个属性 shopItemTitle，但没有一个 shopITitle 属性。

This line

这条线

self.shopItemTitle.text = self.shopITitle;

Does not make sense.

没有意义。

If you are trying to fetch a title from an object of class "shopObjects", then you would need something like this:

如果您试图从“shopObjects”类的对象中获取标题，那么您需要这样的东西：

shopObjects *someShopObject = //code to fetch a shopObject
self.shopItemTitle.text = someShopObject.shopITitle;

回答by Kayce Basques

You'll also see this error if you have an object instance which is the same name as a class, and you mistakenly operate on the class, not your instance (thanks, Xcode auto-complete).

如果您有一个与类同名的对象实例，并且您错误地操作了该类，而不是您的实例（感谢 Xcode 自动完成），您也会看到此错误。

For example, suppose that you have a view controller SetSignsViewControllerand you create an instance of the view controller called setSignsViewController:

例如，假设您有一个视图控制器SetSignsViewController并创建了一个名为 的视图控制器实例setSignsViewController：

SetSignsViewController *setSignsViewController =
    (SetSignsViewController *) uiNavigationController.topViewController;

You want to set the name of a property called openHouseLocation:

您想设置名为 的属性的名称openHouseLocation：

SetSignsViewController.openHouseLocation = self.openHouseLocation;

This yields Property 'openHouseLocation' not found on object of type 'SetSignsViewController'because you're operating on SetSignsViewController, not setSignsViewController(first letter should be s, not S). What you really meant to do was:

这Property 'openHouseLocation' not found on object of type 'SetSignsViewController'是因为您正在操作SetSignsViewController，而不是setSignsViewController（第一个字母应该是s，不是S）。你真正想做的是：

setSignsViewController.openHouseLocation = self.openHouseLocation;

回答by Tendulkar

Try to @synthesizethe variables in .m file of ShopObjects.

尝试使用@synthesizeShopObjects 的 .m 文件中的变量。