Xcode 基础知识：声明具有整数属性的自定义类并在另一个类中使用它
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11596307/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Xcode basics: Declare custom class with integer properties and use it in another class
提问by InRainbows
Trying to do something really simple, but can't figure out the syntax.
试图做一些非常简单的事情，但无法弄清楚语法。
I have a class called Word.h which has 8 properties, strings and integers. For the sake of keeping things simple, I'll stick to 2 here:
我有一个名为 Word.h 的类，它有 8 个属性、字符串和整数。为了简单起见，我将在这里坚持 2：
#import <UIKit/UIKit.h>
@interface Word : NSObject
@property (nonatomic, strong) NSString *word;
@property (nonatomic, strong) NSNumber *wordLevel;
@end
Both properties are synthesised in the .m file
这两个属性都在 .m 文件中合成
I then want to create some objects in another file (UIViewController). In the .h file I have this:
然后我想在另一个文件（UIViewController）中创建一些对象。在 .h 文件中，我有这个：
#import "Word.h"
and in the .m file, this:
在 .m 文件中，这个：
Word *newWord = [[Word alloc] init];
[newWord setWord:@"theorise"];
[newWord setWordLevel:6];
Word *newWord1 = [[Word alloc] init];
[newWord setWord:@"implicit"];
[newWord setWordLevel:7];
Word *newWord2 = [[Word alloc] init];
[newWord setWord:@"incredible"];
[newWord setWordLevel:9];
I now get an error message "Implicit conversion of 'int' to 'NSNumber *' is disallowed with ARC"
我现在收到一条错误消息“ARC 不允许将‘int’隐式转换为‘NSNumber *’”
What am I doing wrong...is the property defined incorrectly in the class file?? How do I access this property. It works fine with the string.
我做错了什么……是在类文件中错误地定义了属性吗？？我如何访问此属性。它适用于字符串。
I will also want to access the properties later - how do I do that...for example:
我还想稍后访问这些属性 - 我该怎么做……例如：
cell.label1.text = [newWord2 wordLevel];
Is this the right syntax???
这是正确的语法吗？？？
Hoping someone can help me, tearing clumps of hair out here! M
希望有人可以帮助我，在这里撕掉一团头发！米
采纳答案by torrey.lyons
You declared wordLevelto be an NSNumber, an object. You are treating it in your code like it is a plain C int. You have to decide which your want it to be and treat it that way consistently. For example, for a plain C intproperty you would instead declare:
你声明wordLevel为一个NSNumber, 一个对象。你在你的代码中对待它就像它是一个普通的 C int。你必须决定你想要的是什么，并始终如一地对待它。例如，对于普通的 Cint属性，您将改为声明：
@property (nonatomic, assign) int wordLevel;
On the other hand if you really want wordLevelto be an NSNumberyou need to use the setter like this:
另一方面，如果你真的想wordLevel成为一个NSNumber你需要像这样使用 setter：
[newWord setWordLevel:[NSNumber numberWithInt:6]];
