UIScrollView

属性

//内容的偏移量（可以让scrollView默认滚动到某个位置，Y坐标为正数时往下便宜，反之则反）（当偏移量小于0时，此偏移 拖动会回弹）
@property(nonatomic) CGPoint contentOffset;                  // default CGPointZero
//内容的大小（scrollView能滚动的范围大小）
@property(nonatomic) CGSize  contentSize;                    // default CGSizeZero
//可已将contentView向四面八方偏移
@property(nonatomic) UIEdgeInsets   contentInset;                   // default UIEdgeInsetsZero. add additional scroll area around content
//弹性
@property(nonatomic) BOOL    bounces; //  default YES. if YES, bounces past edge of content and back again
//最小放大倍数
@property(nonatomic) CGFloat minimumZoomScale;     //    default is 1.0   
//最大放大倍数
@property(nonatomic) CGFloat maximumZoomScale;     //    default is 1.0. must be > minimum zoom scale to enable zooming  
//水平指示器
@property(nonatomic) BOOL    showsHorizontalScrollIndicator; //   default YES. show indicator while we are tracking. fades out after tracking
//垂直指示器
@property(nonatomic) BOOL    showsVerticalScrollIndicator;   //   default YES. show indicator while we are tracking. fades out after tracking
//是否激活分页
@property(nonatomic,getter=isPagingEnabled) BOOL pagingEnabled __TVOS_PROHIBITED;//   default NO. if YES, stop on multiples of view bounds

代理方法

//只要滚动了就会一直在触发此方法（可以用它来实现下拉图片放大）
- (void)scrollViewDidScroll:(UIScrollView *)scrollView;   
{
//    NSLog(@" scrollViewDidScroll");
    NSLog(@"ContentOffset  x is  %f,yis %f",scrollView.contentOffset.x,scrollView.contentOffset.y);
}
//将要开始拖拽的时候执行
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView;   
{
   NSLog(@"scrollViewWillBeginDragging");
}
//结束拖拽的时候执行
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate; 
{
   NSLog(@"scrollViewDidEndDragging");
}
//滑动ScrollView将要开始减速时
- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView;   
{
   NSLog(@"scrollViewWillBeginDecelerating");
}

//减速停止了时执行
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView;   
{
   NSLog(@"scrollViewDidEndDecelerating");
}
//滚动动画停止时执行,代码改变时出发,也就是setContentOffset改变时
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView;
{
   NSLog(@"scrollViewDidEndScrollingAnimation");
}
//设置放大缩小的视图，要是uiscrollview的subview
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView;   
{
   NSLog(@"viewForZoomingInScrollView");
    return viewA;
}
//完成放大缩小时调用
- (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale; 
{
    viewA.frame=CGRectMake(50,0, 100, 400);
   NSLog(@"scale between minimum and maximum. called after any 'bounce' animations");
}// scale between minimum and maximum. called after any 'bounce' animations

//点击状态栏是否回到最顶部（不管返回YES或NO，当你点击状态栏时它都会来调用这个方法）
- (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView;   
{
    NSLog(@"scrollViewShouldScrollToTop");
   return YES;
}
//当回到最顶部的时候调用
- (void)scrollViewDidScrollToTop:(UIScrollView *)scrollView;     
{
    NSLog(@"scrollViewDidScrollToTop");
}