objective-c - 在 Objective-C 中分配一个 IBOutlet

Question

代码生成器 Accessorizer可以选择分配 IBOutlets 而不是保留它们。例如，比较这两条生成的行:

@property(nonatomic,retain)IBOutlet UIImageView *backgroundView;
@property(nonatomic,assign)IBOutlet UIImageView *backgroundView;

为什么我要分配 IBOutlets，同时保留所有其他属性？

Answer 1

用法取决于 memory management guide 中指定的平台:

"The behavior of outlets depends on the platform (see “Mac OS X Desktop” and “iPhone”), so the actual declaration differs:

  For Mac OS X, you should use:

  @property (assign) IBOutlet UserInterfaceElementClass *anOutlet;

  For iPhone OS, you should use:

  @property (nonatomic, retain) IBOutlet UIUserInterfaceElementClass *anOutlet;"