我試圖在_pageControl.currentPage
處於確切頁碼時觸發一個方法,但問題在於當用戶滾動到另一個頁面時,編譯器在仍然滾動時檢測到新頁面!滾動完成後,我需要啓動我的方法!這是我的代碼:UIPageControl和scrollViewDidScroll問題
- (void)setupPageScroll {
_pageControl.currentPage = 0;
_pageControl.numberOfPages = 5;
[_scrollView setContentSize:CGSizeMake(_scrollView.frame.size.width * _pageControl.numberOfPages, _scrollView.frame.size.width)];
_scrollView.delegate = self;
[self createPageWithView:_logo forPage:0];
[self createPageWithView:_news forPage:1];
}
- (void)createPageWithView:(UIView *)iview forPage:(int)page
{
UIView *newView = [[UIView alloc] initWithFrame:
CGRectMake(_scrollView.frame.size.width * page, 0, _scrollView.frame.size.width, _scrollView.frame.size.height)];
[newView addSubview:iview];
[_scrollView addSubview:newView];
}
- (IBAction)pageChanged:(id)sender {
CGRect pageRect = CGRectMake(_pageControl.currentPage * _scrollView.frame.size.width, 0, _scrollView.frame.size.width, _scrollView.frame.size.height);
[_scrollView scrollRectToVisible: pageRect animated: YES];
}
- (void)scrollViewDidScroll: (UIScrollView *) sView
{
CGFloat offset = _scrollView.contentOffset.x;
CGFloat pageSize = _scrollView.frame.size.width;
int page = floor((offset + (pageSize/2))/pageSize);
_pageControl.currentPage = page;
switch (_pageControl.currentPage) {
case 0:
NSLog(@"1");
break;
case 1:
NSLog(@"2");
break;
default:
break;
}
}
這裏是編譯器的結果:
2014年8月27日13:48:35.344 TADAEX [45131:60B] 1 2014年8月27日13:48:35.361 TADAEX [45131:60b] 1 2014-08-27 13:48:35.378 TADAEX [45131:60b] 1 2014-08-27 13:48:37.248 TADAEX [45131:60b] 1 2014-08-27 13: 48:37.265 TADAEX [45131:60b] 1 2014-08-27 13:48:37.282 TADAEX [45131:60b] 1 2014-08-27 13:48:37.299 TADAEX [45131:60b] 2 2014-08- 27 13:48:38.076 TADAEX [45131:60b] 2 2014-08-27 13:48:38.076 TADAEX [45131:60b] 2 TADAEX [45131:60b] 2 2014-08-27 13:48:38.076 TADAEX [45131:60b] 2014-08-27 13:48:38.076 TADAEX [45131:60b] 2 2014-08-27 13:48:38.076 TADAEX [45131:60b] 2 2014-08-27 13:48:38.076 TADAEX [45131: 60b] 2
正如你看到編譯器重複給出NSLog
輸出!而不是pageControl是在確切的頁碼。
是的,這是正常的。 scrollViewDidScroll在用戶滾動時觸發。 – idmean 2014-08-27 09:24:53
更好的選擇是使用if - else而不是Switch case。你可以這樣做,如果(頁面== 1) - > NSLog(@「1」); – Mohit 2014-08-27 09:33:59