PageControl（弹性滚动）

使用网上源码KYAnimatedPageControl

    self.pageControl = [[KYAnimatedPageControl alloc]initWithFrame:CGRectMake(CGRectGetWidth(self.view.bounds)/2-50, CGRectGetHeight(self.view.bounds) - 100, 100, 50)];
    self.pageControl.pageCount = 4;//数量
    self.pageControl.unSelectedColor = [UIColor colorWithWhite:0.9 alpha:1];//未滑动的颜色
    self.pageControl.selectedColor = [UIColor redColor];//滑动的颜色
    self.pageControl.bindScrollView = _scrollView; //需要绑定
    self.pageControl.shouldShowProgressLine = YES;//填充，小球之前的线条变色
    self.pageControl.indicatorStyle = IndicatorStyleGooeyCircle;//样式
    self.pageControl.indicatorSize = 15; //圆圈大小
    self.pageControl.swipeEnable = YES;//这有啥用
    [self.pageControl display];//设置完所有参数调用
    
    [self.view addSubview:self.pageControl];
    
    self.pageControl.didSelectIndexBlock = ^(NSInteger index){
        NSLog(@"Did Selected index : %ld",(long)index);
    };

 UIScrollViewDelegate：

#pragma mark - <UIScrollViewDelegate>

-(void)scrollViewDidScroll:(UIScrollView *)scrollView{
    
    //Indicator动画
    [self.pageControl.indicator animateIndicatorWithScrollView:scrollView andIndicator:self.pageControl];
    
    if (scrollView.dragging || scrollView.isDecelerating || scrollView.tracking) {
        //背景线条动画
        [self.pageControl.pageControlLine animateSelectedLineWithScrollView:scrollView];
    }
    
}

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
    
    self.pageControl.indicator.lastContentOffset = scrollView.contentOffset.x;
    
}

-(void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView{
    
    
    [self.pageControl.indicator restoreAnimation:@(1.0/self.pageControl.pageCount)];
    
}

- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView{
    self.pageControl.indicator.lastContentOffset = scrollView.contentOffset.x;
}

demo下载地址：http://pan.baidu.com/s/1pJn66pX

效果图：