blocks|key|1330204|text|为您的对象创建一个全局变量，并在创建时将其存储在那里。您可以在init方法(可能不是很好的风格)中，或者从调用者或通过接口构建器将其连接起来。只要让你的变量在使用它的文件中是已知的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1330205|或者--嗯--使用某种单例模式，直接从那个类中获取实例。看起来干净多了。|1330206|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

Make a global variable for your object and store it there on creation. You can wire that up in the init method (probably bad style), or from the caller or via interface builder. Just make your variable known in the files that use it.

Or - well - use some kind of singleton pattern and get the instance directly from that class. Looks much cleaner.

blocks|key|5240042|text|认真使用单例。如果你不喜欢他们，因为你不知道代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5240043|@interface+Order+:+NSObject+{
NSMutableArray+*order;
}

@property+(nonatomic,+retain)+NSMutableArray+*order;

%2B+(Order+*)sharedInstance;

@end

#import+"Order.h"


@implementation+Order

@synthesize+order;

%2B(Order+*)sharedInstance+{
static+Order+*myInstance+=+nil;

@synchronized(self)+{
++++if(!myInstance)+{
++++++++myInstance+=+[[Order+alloc]+init];
++++++++}
++++}
return+myInstance;
}

-(void)dealloc+{
++++[order+release];
++++[super+dealloc];

}
@end|code-block|syntax|javascript|5240044|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Seriously use a singleton. In case you don't like them cause you don't know the code:

<pre><code>@interface Order : NSObject {
NSMutableArray *order;
}

@property (nonatomic, retain) NSMutableArray *order;

+ (Order *)sharedInstance;

@end

#import "Order.h"


@implementation Order

@synthesize order;

+(Order *)sharedInstance {
static Order *myInstance = nil;

@synchronized(self) {
 if(!myInstance) {
 myInstance = [[Order alloc] init];
 }
 }
return myInstance;
}

-(void)dealloc {
 [order release];
 [super dealloc];

}
@end
</code></pre>

blocks|key|1456505|text|如果你不喜欢这个模式或者它不适合你，那么就没有必要使用单例模式。假设您在第一个视图控制器中创建了第二个视图控制器，只需在第二个视图控制器中为模型对象声明一个ivar和属性，并在实例化它时，将模型对象分配给此属性。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1456506|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

There's no need to use a singleton if you don't like the pattern or if it doesn't fit. Assuming you are creating your second view controller in the first one, just declare an ivar and property for your model object in your second view controller and when you instantiate it, assign the model object to this property.

blocks|key|5240176|text|恩。你好。核心数据对你来说不是一个足够好的框架吗？它允许您使用单个持久存储和多个上下文来管理更新和合并更改，以响应通知。我可能在这里有点过分，但是看到你如何在你的第一个问题中以一个被广泛接受的模式的强烈意见开始这个问题，这表明你没有花费太多的时间来发现iOS中的objective+C运行时和基础类如何协作来实现任务。在任何软件中，一个对象并且只有一个对象拥有特定的资源。你应该拥抱单例。我建议你花点时间阅读http://www.cocoadesignpatterns.com/。哦，对了，看看KVO的意思。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|5240177|entityMap|0|LINK|mutability|MUTABLE|url|http://www.cocoadesignpatterns.com/^0|5O|Z|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

Um. Hello. Isn't Core Data a good enough framework for you? It allows you to have a single persistent store and multiple contexts to manage updates and merging of changes in response to notifications. I may be out of line here, but seeing how you start the question with a strong opinion about a well accepted pattern in your first question indicates that you have not spent much time discovering the ways in which the objective c runtime and Foundation classes in iOS can collaborate to achieve a task. In any software, one object and only one object owns a specific resource. You should embrace singletons. I suggest you spend some time reading <a href="http://www.cocoadesignpatterns.com/" rel="nofollow noreferrer">http://www.cocoadesignpatterns.com/</a>. Oh yeah, check out the meaning of KVO.

blocks|key|5240183|text|为什么不让它成为你的应用代理的一个属性呢？通过这种方式，您不必使用单例模式，但您可以利用Apple已经使用的单例模式。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5240184|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Why not make it a property of your app delegate? That way you don't have to use the singleton pattern but you are taking advantage of Apple's already existing usage of the singleton pattern.

blocks|key|3772019|text|不要忘记Objective-C是C的超集。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3772020|基本上，数据类是一个普通的C+struct。|offset|length|style|CODE|3772021|如果要从另一个类访问该类的变量，请将其设置为全局变量。|3772022|mydata.h：|3772023|struct+MyData+{
++++//+Whatever+data+fields+that+you+need,+e.g.:
++++NSInteger+value;
};

extern+struct+MyData+mydata;|code-block|syntax|javascript|3772024|mydata.c：|3772025|struct+MyData+mydata+=+{
++++//+Whatever+initial+value+that+you+find+relevant,+e.g.:
++++.value+=+42;
};|3772026|entityMap^0|0|F|6|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@$D|Y|E|Z|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|10|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|11|8|@]|9|@]|A|$]]|$1|L|3|M|5|N|7|12|8|@]|9|@]|A|$O|P]]|$1|Q|3|R|5|6|7|13|8|@]|9|@]|A|$]]|$1|S|3|T|5|N|7|14|8|@]|9|@]|A|$O|P]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

Don't forget that Objective-C is a superset of C.

Basically, a data class is a plain C <code>struct</code>.

If you want to access a variable of that class from another class, make it global.

mydata.h:

<pre><code>struct MyData {
 // Whatever data fields that you need, e.g.:
 NSInteger value;
};

extern struct MyData mydata;
</code></pre>

mydata.c:

<pre><code>struct MyData mydata = {
 // Whatever initial value that you find relevant, e.g.:
 .value = 42;
};
</code></pre>

First off, I despise singletons with a passion. Though I should probably be trying to use one, I just don't want to. I want to create a data class (that is instantiated only once by a view controller on loading), and then using a different class, message the crap out of that data instance until it is brimming with so much data, it smiles. 

So, how do I do that? I made a pointer to the instance of the data class when I instantiated it. I'm now over in a separate view controller, action occurs, and I want to update the initial data object. I think I need to reference that object by way of pointer, but I have no idea how to do that. Yes, I've set properties and getters and setters, which seem to work, but only in the initial view controller class.

How do I reference a pointer from a different class?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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首先，我轻视有激情的单身人士。虽然我可能应该尝试使用一个，但我就是不想。我想创建一个数据类(它只在加载时由视图控制器实例化一次)，然后使用另一个类，将数据实例中的垃圾消息传出，直到它充满了如此多的数据，它笑了。那么，我该怎么做呢？在实例化数据类时，我创建了一个指向数据类实例的指针。我现在在一个单独的视图控制器中，动作发...

问如何引用来自不同类的指针？
EN

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问如何引用来自不同类的指针？EN