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iPod:非原子iphone的唯一含义是什么?在iPod Touch上使用这样的属性安全吗?

ipod-touch iphone

3

sixtyfootersdude · 技术社区 · 14 年前

在里面 CLLocation Class Reference 在properties部分下面 coordinate :

coordinate
The geographical coordinate information. (read-only)

@property(readonly, NS_NONATOMIC_IPHONEONLY) CLLocationCoordinate2D coordinate
Discussion
When running in the simulator, Core Location assigns a fixed set of coordinate values to this property. You must run your application on an iOS-based device to get real location values.

Special Considerations
In iOS, this property is declared as nonatomic. In Mac OS X, it is declared as atomic.

我只是好奇这意味着什么: @property(readonly, NS_NONATOMIC_IPHONEONLY) . 特别是 NS_NONATOMIC_IPHONEONLY 部分。在我看来,我可以通过iPod touch访问它。

我遗漏了什么吗?从iPod touch使用它安全吗?

1 回复 | 直到 14 年前

1

5

gcamp 14 年前

核心定位在Mac OS X和iOS(ne-iPhone操作系统)之间共享。

在这里, NS_NONATOMIC_IPHONEONLY

它在TargetConditionals.h中定义如下。

// Marks APIs whose iPhone versions are nonatomic, that is cannot be set/get from multiple threads safely without additional synchronization
#if !defined(NS_NONATOMIC_IPHONEONLY)
    #if TARGET_OS_IPHONE
    #define NS_NONATOMIC_IPHONEONLY nonatomic
    #else
    #define NS_NONATOMIC_IPHONEONLY
    #endif
#endif