ScrollView + n个view
1.storyboard布局一个ScrollView
2.拖出两个输出口，定义三个属性
@property (weak, nonatomic) IBOutlet UIScrollView *XMScrollView; @property (weak, nonatomic) IBOutlet UIView *scrollContentView; ///第一次按下 @property (nonatomic) BOOL isBeginScroll; ///开始结束滑动scroll动画 @property (nonatomic) BOOL isBeginAnimationScroll; ///开始坐标 @property (nonatomic) NSInteger beginX;
3.在viewDidAppear中重新设置scrollContentView的布局宽和tableVIew大小和位置
///遍历布局
for (NSLayoutConstraint *constraint in self.scrollContentView.constraints) {
///判断布局是不是自己想要的 NSLayoutAttribute类型
if (constraint.firstAttribute == NSLayoutAttributeWidth) {
[constraint setConstant:self.view.frame.size.width*3];
}
}
[self.tableView1 setFrame:CGRectMake(0, 0, self.view.frame.size.width, scrollViewContentViewFrame.size.height)];
[self.tableView2 setFrame:CGRectMake(self.view.frame.size.width, 0, self.view.frame.size.width, scrollViewContentViewFrame.size.height)];
[self.tableView3 setFrame:CGRectMake(self.view.frame.size.width*2, 0, self.view.frame.size.width, scrollViewContentViewFrame.size.height)];4.添加scrollView的代理方法
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView{
///开始滑动scrollView
self.isBeginScroll = YES;
///开始滑动scrollView的位置
self.beginX = scrollView.contentOffset.x;;
}
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset{
///停下自动滑动scrollView
[self.XMScrollView setContentOffset:CGPointZero animated:YES];
///结束滑动scrollView
self.isBeginScroll = NO;
///开始滑动动画
self.isBeginAnimationScroll = YES;
}
///结束滑动动画
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView{
if (self.isBeginAnimationScroll) {
CGFloat currentX = scrollView.contentOffset.x;
NSInteger page = currentX/self.view.frame.size.width;
///判断到哪一页了,加载数据
switch (page) {
case 0:
break;
case 1:
break;
case 2:
break;
default:
break;
}
}
self.isBeginAnimationScroll = NO;
}5.在viewDidLoad中添加监听
///页面切换ScrollView self.XMScrollView.delegate = self; [self addObserver:self forKeyPath:@"isBeginScroll" options:NSKeyValueObservingOptionNew context:nil];
6.通过监听实现滑动结束后自动滑动
-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSKeyValueChangeKey,id> *)change context:(void *)context{
if (!self.isBeginScroll) {
CGFloat offSetX = self.XMScrollView.contentOffset.x;
NSInteger scale = (int)(offSetX/self.view.frame.size.width);
if (offSetX >= self.beginX) {
[self.XMScrollView setContentOffset:CGPointMake((scale+1)*self.view.frame.size.width, 0) animated:YES];
}
if (offSetX < self.beginX) {
if (self.beginX >= self.view.frame.size.width){
[self.XMScrollView setContentOffset:CGPointMake((scale)*self.view.frame.size.width, 0) animated:YES];
}
}
}
}
