UIScrollView 是一个可滚动的视图列表，在app中非常常见。下面简单的介绍一下UIScrollView 的用法。可实现代理UIScrollViewDelegate
// 实例化UIScrollViewUIScrollView* _scrollView = [[UIScrollView alloc] init];// 获取屏幕大小UIScreen* screen = [UIScreen mainScreen];// 设置滚动视图大小_scrollView.frame = CGRectMake(0, 0, screen.bounds.size.width, screen.bounds.size.height);// 设置滚动视图内容画布大小,当内容画布大小超过frame时候会出现滚动_scrollView.contentSize = CGSizeMake(screen.bounds.size.width, maxViewNum * screen.bounds.size.height);// 设置回弹效果_scrollView.bounces = YES;// 设置可滚动_scrollView.scrollEnabled = YES;// 设置显示Y轴滚地图_scrollView.showsVerticalScrollIndicator = YES;[self.view addSubview:_scrollView];
属性
| 名称 | 类型 | 说明 | 默认值 |
|---|---|---|---|
| contentOffset | CGPoint | 滚动视图内容当前滚动的位置 | 0,0 |
| contentSize | CGSize | 滚动视图内容当前大小 | |
| directionalLockEnabled | BOOL | 滚动时候尝试锁定一个方向滚动 | NO |
| bounces | BOOL | 启用回弹效果 | YES |
| alwaysBounceVertical | BOOL | 始终启用垂直回弹效果 | NO |
| alwaysBounceHorizontal | BOOL | 始终启用水平回弹效果 | NO |
| pagingEnabled | BOOL | 翻页滚动模式 | NO |
| scrollEnabled | BOOL | 启动滚动 | NO |
| showsVerticalScrollIndicator | BOOL | 显示垂直滚动条 | YES |
| showsHorizontalScrollIndicator | BOOL | 显示水平滚动条 | YES |
| indicatorStyle | UIScrollViewIndicatorStyle | 滚动条样式 | UIScrollViewIndicatorStyleDefault |
| indicatorStyle | UIScrollViewIndicatorStyle | 滚动条样式 | UIScrollViewIndicatorStyleDefault |
API
- (void)setContentOffset:(CGPoint)contentOffset animated:(BOOL)animated使用动画设置滚动位置- (void)scrollRectToVisible:(CGRect)rect animated:(BOOL)animated使用动画滚动到指定矩形区域- (void)setZoomScale:(CGFloat)scale animated:(BOOL)animated动画设置缩放- (void)zoomToRect:(CGRect)rect animated:(BOOL)animated动画移动到指定矩形区域
代理协议函数
- (void)scrollViewDidScroll:(UIScrollView *)scrollView视图发生滚动时触发- (void)scrollViewDidZoom:(UIScrollView *)scrollView视图发生放大触发- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView视图开始拖动时候触发- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset拖动结束触发- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate减速时候触发，decelerate 表示减速后会继续减速。- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView手指抬起时- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView视图停止滚动时候触发- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollViewsetContentOffset执行完后触发，如果没有动画则不触发。- (void)scrollViewWillBeginZooming:(UIScrollView *)scrollView withView:(nullable UIView *)view视图即将缩放时候触发- (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView返回一个YES返回到顶部- (void)scrollViewDidScrollToTop:(UIScrollView *)scrollView滚动动画时候触发，如果在顶部立即触发。
