@protocol MDCFlexibleHeaderViewDelegate <NSObject>
The MDCFlexibleHeaderViewDelegate protocol allows a delegate to respond to changes in the header view’s state.
The delegate is typically the UIViewController that owns this flexible header view.
Informs the receiver that the flexible header view’s preferred status bar visibility has changed.
- (void)flexibleHeaderViewNeedsStatusBarAppearanceUpdate: (nonnull MDCFlexibleHeaderView *)headerView;
Informs the receiver that the flexible header view’s frame has changed.
The frame may change in response to scroll events of the tracking scroll view. The receiver should use the MDCFlexibleHeaderView scrollPhase APIs to determine which phase the header’s frame is in.
- (void)flexibleHeaderViewFrameDidChange: (nonnull MDCFlexibleHeaderView *)headerView;