根据headerView位置改变headerView颜色(collectionView/tableview)

滑动时,tableview中的headerView 的frame不断改变,collectionView的headerView的center不断改变.
so
tableview:

-(void)setFrame:(CGRect)frame{
    [super setFrame:frame];
    CGRect rect =  [self.superview convertRect:frame toView:[UIApplication sharedApplication].keyWindow];
    if (rect.origin.y > 65 && rect.size.height > 0 && ![self.backgroundColor isEqual:[UIColor whiteColor]]) {
        [self setBackgroundColor:[UIColor whiteColor]];
    }else if(rect.origin.y < 65 && rect.size.height > 0 && ![self.backgroundColor isEqual:UIColorFromRGB(0xff3333)]){
        [self setBackgroundColor:UIColorFromRGB(0xff3333)];
    }
}

collectionView:

#import "CollectionReusableView.h"
@interface CollectionReusableView(){
    CGFloat centerY;
}
@end

@implementation CollectionReusableView

-(void)setFrame:(CGRect)frame{
    [super setFrame:frame];
    centerY = self.frame.origin.y + self.frame.size.height/2.0;
}

-(void)setCenter:(CGPoint)center{
    [super setCenter:center];
    if (center.y < centerY + 1  && ![self.backgroundColor isEqual:[UIColor whiteColor]]) {
        [self setBackgroundColor:[UIColor whiteColor]];
    }else if(center.y > centerY + 1   > 0 && ![self.backgroundColor isEqual:[UIColor redColor]]){
        [self setBackgroundColor:[UIColor redColor]];
    }
}

@end