一些常见的属性选项

// 摘抄自React-Core源码 RCTAccessibilityManager.h

// 基本都是用nonatomic 效率更高

/// NSDictionary NSArray都用copy
@property (nonatomic, copy) NSDictionary<NSString *, NSNumber *> *multipliers;

@property (nonatomic, copy, readonly) NSArray<RCTDevMenuItem *> *presentedItems;

// 不可变字符串也用copy
@property (nonatomic, copy) NSString *gender;

// block也用copy
@property (nonatomic, copy) RCTBubblingEventBlock onRNCSliderValueChange;

// 基本数据类型都用assign
@property (nonatomic, assign) BOOL isBoldTextEnabled;

@property (nonatomic, assign) NSUInteger maxReloadAttempts;

@property (nonatomic, assign) float step;

@property (nonatomic, assign) CGFloat blurRadius;

// 枚举也用assign
@property (nonatomic, assign) RCTResizeMode resizeMode;

// 代理一定只能用weak 也一定只能用assign
@property (nonatomic, weak) id<RCTExceptionsManagerDelegate> delegate;

// 普通对象用strong
@property (nonatomic, strong) NSURL *overrideBundleURL;

@property (nonatomic, strong) UIImage *trackImage;

@property (nonatomic, strong, nullable) UIColor *backgroundColor;

注意：

@property (nonatomic, copy) NSMutableArray *mArray;

这种声明真的是自己挖坑了；

你要的是可变对象，但是一 copy 就是不可变对象了，运行时会出问题的；