scrollview的一些代理方法

• //隻要滾動了就會觸發

  - (void)scrollViewDidScroll:(UIScrollView *)scrollView;   

  {

    NSLog(@" scrollViewDidScroll");

  }

  //開始拖拽視圖

  - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView;   

     NSLog(@"scrollViewWillBeginDragging");

  //完成拖拽

  - (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate; 

     NSLog(@"scrollViewDidEndDragging");

  //将開始降速時

  - (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView;   

     NSLog(@"scrollViewWillBeginDecelerating");

  //減速停止了時執行，手觸摸時執行執行

  - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView;   

     NSLog(@"scrollViewDidEndDecelerating");

  //滾動動畫停止時執行,代碼改變時出發,也就是setContentOffset改變時

  - (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView;

     NSLog(@"scrollViewDidEndScrollingAnimation");

  //設定放大縮小的視圖，要是uiscrollview的subview

  - (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView;   

     NSLog(@"viewForZoomingInScrollView");

      return viewA;

  //完成放大縮小時調用

  - (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)view atScale:(float)scale; 

     NSLog(@"scale between minimum and maximum. called after any 'bounce' animations");

  //如果你不是完全滾動到滾軸視圖的頂部，你可以輕點狀态欄，那個可視的滾軸視圖會一直滾動到頂部，那是預設行為，你可以通過該方法傳回NO來關閉它

  - (BOOL)scrollViewShouldScrollToTop:(UIScrollView *)scrollView;   

      NSLog(@"scrollViewShouldScrollToTop");

     return YES;

  - (void)scrollViewDidScrollToTop:(UIScrollView *)scrollView;