解决iOS11 UIScrollView下移问题

iOS11 系统为UIScrollView增加一个contentInsetAdjustmentBehavior属性，默认为UIScrollViewContentInsetAdjustmentAutomatic，要想和iOS11之前显示效果一样的话，只需要写一个分类在+ (void)load方法设置一下就好了

#import "UIScrollView+KJExtension.h"

@implementation UIScrollView (KJExtension)

+ (void)load {

NSLog(@"scrollView调用了load方法");

if (@available(iOS 11.0, *)){

[[self appearance] setContentInsetAdjustmentBehavior:UIScrollViewContentInsetAdjustmentNever];

}

}

@end