self.contentView 裡有時會出這樣的子視圖。。。。
<UILabel: 0x81667f0; frame = (0 0; 0 0); clipsToBounds = YES; userInteractionEnabled = NO; layer = <CALayer: 0x8166880>>
self.contentView 裡有時會出這樣的子視圖。。。。
<UILabel: 0x81667f0; frame = (0 0; 0 0); clipsToBounds = YES; userInteractionEnabled = NO; layer = <CALayer: 0x8166880>>