/**
*  @param frame frame
*  @param titles 标题数组
*  @param delegate 代理
*/
+ (instancetype)titleBarWithFrame:(CGRect)frame titles:(NSArray<NSString *> *)titles delegate:(id<FYScrollTitleBarDelegate>)delegate;
+ (instancetype)titleBarWithFrame:(CGRect)frame titles:(NSArray<NSString *> *)titles;

/// 底部红色指示条
@property (nonatomic, strong) UIImageView *indicator;
/// 所有 button 的父视图
@property (nonatomic, strong) UIScrollView *contentView;
/// 顶部灰色线条
@property (nonatomic, strong) UIImageView *topLine;
/// 底部灰色线条
@property (nonatomic, strong) UIImageView *bottomLine;
/// 当前选中的 button
@property (nonatomic, strong) UIButton *selectedButton;
/// 所有titles
@property (nonatomic, strong) NSArray<NSString *> *titles;
/// 当前选中 button 的index
@property (nonatomic, assign, readonly) NSInteger selectedIndex;
/// 代理
@property (nonatomic, weak) id<FYScrollTitleBarDelegate> delegate;
/// 自己更新 Indicator 位置, 默认为NO
@property (nonatomic, assign) BOOL automicAdjustIndicator;

/// 滚动条更新
- (void)updatePercentX:(CGFloat)precentX;
/// 更新选中的 button
- (void)setSelectedButtonAtIndex:(NSInteger)index;

/**
*  当前选中的 button 的索引回调
*/
- (void)titleBar:(FYScrollTitleBar *)titleBar didSelectedIndex:(NSInteger)index;