我怎样才能使scrollView autoscroll？

Question

我有这样的滚动视图：

self.scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds]; 
self.scrollView.autoresizingMask = UIViewAutoresizingFlexibleHeight; 
self.scrollView.contentSize = CGSizeMake(320,3000); 


_scrollView.frame = CGRectMake(0, 45, 320, 420); 

，我希望把它向下自动滚动速度非常慢到年底，使用户可以看到的内容（如电影学分），最终与键停止/播放，但在触摸界面时遵循用户手势。

我该怎么做？ 谢谢，

Answer 1

这适于代码并获得成功（源http://sugartin.info/2012/01/21/image-sliding-page-by-page-uiscrollview-auto-scrolling-like-image-slider/）

PS：每个图像是280由200

- (void)viewDidLoad 
{ 
[super viewDidLoad]; 

UIScrollView *scr=[[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)]; 
scr.tag = 1; 
scr.autoresizingMask=UIViewAutoresizingNone; 
[self.view addSubview:scr]; 
[self setupScrollView:scr]; 
UIPageControl *pgCtr = [[UIPageControl alloc] initWithFrame:CGRectMake(0, 264, 480, 36)]; 
[pgCtr setTag:12]; 
pgCtr.numberOfPages=10; 
pgCtr.autoresizingMask=UIViewAutoresizingNone; 
[self.view addSubview:pgCtr]; 
} 

    - (void)setupScrollView:(UIScrollView*)scrMain { 
// we have 10 images here. 
// we will add all images into a scrollView & set the appropriate size. 

for (int i=1; i<=10; i++) { 
    // create image 
    UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"sti%02i.jpg",i]]; 
    // create imageView 
    UIImageView *imgV = [[UIImageView alloc] initWithFrame:CGRectMake(20, ((i-1)*scrMain.frame.size.height+100), 280, 200)]; 
    // set scale to fill 
    imgV.contentMode=UIViewContentModeScaleToFill; 
    // set image 
    [imgV setImage:image]; 
    // apply tag to access in future 
    imgV.tag=i+1; 
    // add to scrollView 
    [scrMain addSubview:imgV]; 
} 
// set the content size to 10 image width 
[scrMain setContentSize:CGSizeMake(scrMain.frame.size.width, scrMain.frame.size.height*10)]; 
// enable timer after each 2 seconds for scrolling. 
[NSTimer scheduledTimerWithTimeInterval:2 target:self selector:@selector(scrollingTimer) userInfo:nil repeats:YES]; 


} 

- (void)scrollingTimer { 
// access the scroll view with the tag 
UIScrollView *scrMain = (UIScrollView*) [self.view viewWithTag:1]; 
// same way, access pagecontroll access 
UIPageControl *pgCtr = (UIPageControl*) [self.view viewWithTag:12]; 
// get the current offset (which page is being displayed) 
CGFloat contentOffset = scrMain.contentOffset.y; 
// calculate next page to display 
int nextPage = (int)(contentOffset/scrMain.frame.size.height) + 1 ; 
// if page is not 10, display it 
if(nextPage!=10) { 


    [scrMain scrollRectToVisible:CGRectMake(0, nextPage*scrMain.frame.size.height, scrMain.frame.size.width, scrMain.frame.size.height) animated:YES]; 
    pgCtr.currentPage=nextPage; 
    // else start sliding form 1 :) 


} else { 

    [scrMain scrollRectToVisible:CGRectMake(0, 0, scrMain.frame.size.width, scrMain.frame.size.height) animated:YES]; 
    pgCtr.currentPage=0; 
} 
} 

Answer 2

如果你想水平滚动，你可以设置x，否则设置y滚动垂直。

[_scrollView setContentOffset:CGPointMake(x, y) animated:YES]; 

并相应地修改坐标。

Answer 3

您可以使用：

[_scrollView setContentOffset:CGPointMake(x,y) animated:YES]; 

，并使用X和Y，你可以捕获屏幕上的触摸点。

你也可以做一个动画与CoreAnimation：

[UIScrollView beginAnimations:@"scrollAnimation" context:nil]; 
[UIScrollView setAnimationDuration:1.0f]; 
[scroll setContentOffset:CGPointMake(x, y)]; 
[UIScrollView commitAnimations];