向UIView, UIViewController, UIApplication添加recursiveDescription2方法。除了UIView的（私有）recursiveDescription外，还可以显示

• 视图名称，如果它们是UIView或UIViewController子类实例变量，或如果它们是与检查层次结构的一部分

改进了UIView, UIImage, UIImageView的description方法，添加了

• 与视图相关联的UIViewController类 - 适应了来自Peter Steinberger的swizzled [UIView description]：http://petersteinberger.com/blog/2012/pimping-recursivedescription/
• UIImage和UIImageView得到类似（也来自Peter）的东西
• 因为description用于组成recursiveDescription，所以这些改进在调用recursiveDescription2时也会出现

在调试器中的视图上调用它

po [someView recursiveDescription2]

示例输出

0x08c5d730 'RootViewController:0x757a0b0' <UIView: 0x719ffd0; frame = (0 20; 320 460); autoresize = RM+BM; layer = <CALayer: 0x71a0030>>
| _subview1 <UIView: 0x719fe90; frame = (96 20; 128 27); autoresize = W+H; layer = <CALayer: 0x719fef0>>
| _myButton <UIRoundedRectButton: 0x719ba40; frame = (46 295; 204 44); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x719bb60>>
|    | _tableViewStyleBackground <UIGroupTableViewCellBackground: 0x719c320; frame = (0 0; 204 44); userInteractionEnabled = NO; layer = <CALayer: 0x719c3f0>>
|    | _shadowView <UIImageView: 0x719d8f0; frame = (1 1; 202 43); opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x719dbd0>> - (null)
|    | _titleView <UIButtonLabel: 0x719cfa0; frame = (90 12; 23 19); text = 'log'; clipsToBounds = YES; opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x719d090>>
| _greyBlob <UIView: 0x719ebe0; frame = (46 96; 227 136); autoresize = RM+BM; layer = <CALayer: 0x719aec0>>
|    | _myButton2 <UIRoundedRectButton: 0x719ed60; frame = (20 73; 73 44); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x719ee30>>
|    |    | _tableViewStyleBackground <UIGroupTableViewCellBackground: 0x719ee60; frame = (0 0; 73 44); userInteractionEnabled = NO; layer = <CALayer: 0x719eee0>>
|    |    | _shadowView <UIImageView: 0x719ef50; frame = (1 1; 71 43); opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x719efb0>> - (null)
|    |    | _titleView <UIButtonLabel: 0x719f100; frame = (12 12; 49 19); text = 'Button'; clipsToBounds = YES; opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x719f1f0>>
|    | _imageView <UIImageView: 0x8c81490; frame = (101 9; 106 60); autoresize = RM+BM; userInteractionEnabled = NO; layer = <CALayer: 0x8c81560>>-><UIImage: 0x8c827a0 size:{171, 68}>

在应用程序上调用调试器

po [UIApplication recursiveDescription2]

示例输出

<UIWindow: 0xde15700; frame = (0 0; 320 568); gestureRecognizers = <NSArray: 0xde17dc0>; layer = <UIWindowLayer: 0xde18620>>
| 'RootViewController:0xde189b0' <UIView: 0x8a23390; frame = (0 0; 320 568); autoresize = RM+BM; layer = <CALayer: 0x8a233f0>>
|    | _subview1 <UIView: 0x8a23220; frame = (96 20; 128 135); autoresize = W+H; layer = <CALayer: 0x8a23280>>
|    | _myButton, _button <UIButton: 0x8a1f6f0; frame = (46 295; 246 44); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x8a1f820>>
|    |    | _titleView <UIButtonLabel: 0x8a258b0; frame = (33 13; 179 18); text = 'log recursiveDescription2'; clipsToBounds = YES; opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x8a25960>>
|    | _greyBlob <UIView: 0x8a21630; frame = (46 96; 227 136); autoresize = RM+BM; layer = <CALayer: 0x8a21690>>
|    |    | _myButton2, _button <UIButton: 0x8a1ea20; frame = (20 73; 73 44); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x8a16750>>
|    |    |    | _titleView <UIButtonLabel: 0x8a21c50; frame = (12 13; 48 18); text = 'Button'; clipsToBounds = YES; opaque = NO; userInteractionEnabled = NO; layer = <CALayer: 0x8a21d80>>
|    |    | _imageView <UIImageView: 0x8a184c0; frame = (101 9; 106 60); autoresize = RM+BM; userInteractionEnabled = NO; layer = <CALayer: 0x8a18990>>-><UIImage: 0x8a22350 size:{171, 68}> - (null)

安装

• 将HOURecursiveDescripion.m文件拖放到您的Xcode项目，并将其添加到目标。它仅在DEBUG构建中被编译。如果您想从代码中调用它，HOURecursiveDescripion.h是可选的。

或者使用CocoaPods

pod 'HOURecursiveDescription'

它如何工作

• 使用nextResponder找到与UIView关联的UIViewController。
• 通过检查涉及对象类使用objc运行时方法，遍历ivar名称和实例指针地址
• 然后使用正则表达式操作原始recursiveDescription的返回值