•UIButton快捷获取属性值
•UIButton有很多种状态,它提供了一些便捷属性,可以直接获取当前状态下的文字、文字颜色、图片等
•@property(nonatomic,readonly,retain) NSString *currentTitle;
•@property(nonatomic,readonly,retain) UIColor *currentTitleColor;
•@property(nonatomic,readonly,retain) UIImage *currentImage;
•@property(nonatomic,readonly,retain) UIImage *currentBackgroundImage;