目标C：什么是创建和使用动态布尔数组的最佳方式？ [英] Objective C: What is the best way to create and use a dynamic boolean array?

问题描述

我一直在挣扎与创建，访问和从动态布尔数组的一个多星期，现在更新价值的最佳途径。

I have been struggling with the best way of creating, accessing and updating values from a dynamic boolean array for more than a week now.

@interface myDelegate : NSObject
{
   NSMutableArray *aShowNote;
}
@property (nonatomic, copy) NSMutableArray *aShowNote;

这是我是如何初始化我的数组：

This is how I have initialised my array:

NSMutableArray *aShow = [[NSMutableArray alloc] init]; 
for (i=0; i < c; i++) 
    [aShow addObject:[NSNumber numberWithBool:false]];
self.aShowNote = aShow;

这似乎是工作确定，但我很困惑，为什么每个元素都具有相同的地址初始化。

This seems to work OK but I'm baffled why each element is initialised with the same address.

那么是什么我发现在我的研究，到目前为止是看来你需要的，如果你想改变它的值来代替对象：

But then what I've discovered in my research so far is that is seems that you need to replace the object if you want to change its value:

myDelegate *appDelegate = (myDelegate *)[[UIApplication sharedApplication] delegate];
NSInteger recordIndex = 1;

NSNumber *myBoolNo = [appDelegate.aShowNote objectAtIndex:recordIndex];
BOOL showNote = ![myBoolNo boolValue];

[appDelegate.aShowNote replaceObjectAtIndex:recordIndex withObject:[NSNumber numberWithBool:showNote]];

但这种做法似乎只是过度复杂（它崩溃太）。

but this approach just seems to be over complicated (and it crashes too).

终止应用程序由于未捕获的exception'NSInvalidArgumentException'，原因：' - [__ NSArrayI replaceObjectAtIndex：withObject：]：无法识别的选择发送到实例0x5b51d00

任何指针，以改善这个code（当然，使其工作）将非常感激地接受。

Any pointers to improve this code (and of course to make it work) would be very gratefully received.

感谢

Iphaaw

推荐答案

问题是，复制在属性复制分配的对象。而副本创建不可变对象。

the problem is that copy in a property copies the assigned object. And copy creates immutable objects.

更改属性来读取： @属性（非原子，保留）的NSMutableArray * aShowNote;

我认为没有太大改善，从我知道这是去，如果你想要一个NSArray与布尔值的方式。

And I think there is not much to improve, from what I know this is the way to go if you want an NSArray with booleans.

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