转自:http://www.writecodes.com/develop/395.html
前几天在工作中用到如何知道UIScrollView 的第一个page 和最后一个page ,是很小的问题了。个人感觉比叫常用,就分享下!
关键代码如下:
首先要加入代理“UIScrollViewDelegate”
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| @interface ScrollViewController : UIViewController<UIScrollViewDelegate> |
第二呢 就是在定义UIScrollView的对象时加入
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| _scrollView.delegate = self; |
最后就是判断了:
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| - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
[self loadPageViewsDelay];
if(scrollView.contentOffset.x >= scrollView.contentSize.width-scrollView.frame.size.width)
{
UIAlertView * alert = [[UIAlertView alloc]initWithTitle:@"" message:@"您已移动到最后一页" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil];
[alert show];
[alert release];
}
if(scrollView.contentOffset.x <= 0)
{
UIAlertView * alert = [[UIAlertView alloc]initWithTitle:@"" message:@"您已移动到第一页" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil];
[alert show];
[alert release];
}
} |
这样就ok了,哈哈!
效果图:

源代码demo下载