.h文件
[plain]
@interface Interface1 : UIViewController {
IBOutlet UIScrollView *scroller;
IBOutlet UILabel *warnung;
}
@property (nonatomic, retain) IBOutlet UIScrollView* scrollView;
.m文件
[plain]
– (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
CGPoint bottomOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentSize.height – self.scrollView.bounds.size.height);
[self.scrollView setContentOffset:bottomOffset animated:NO];
CGPoint newOffset = self.scrollView.contentOffset;
newOffset.y = 0;
[self.scrollView setContentOffset:newOffset animated:YES];
}
– (void)viewDidLoad
{
[scroller setScrollEnabled:YES];
[scroller setContentSize:CGSizeMake(320, 420)];
[super viewDidLoad];
}
使用setContentOffset:animated:
[plain]
UIScrollView *scrollView = …;
CGPoint newOffset = scrollView.contentOffset;
newOffset.y = 0;
[scrollView setContentOffset:newOffset animated:YES];
如果需要開場動畫的效果，在scrollView的viewcontroller實現
[plain]
– (void)viewDidLoad
{
[super viewDidLoad];
// …
CGPoint bottomOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentSize.height – self.scrollView.bounds.size.height);
[self.scrollView setContentOffset:bottomOffset animated:NO];
}
– (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
CGPoint newOffset = self.scrollView.contentOffset;
newOffset.y = 0;
[self.scrollView setContentOffset:newOffset animated:YES];
}
移動的慢點，用timer實現：
[plain]
– (void)viewDidLoad
{
[super viewDidLoad];
// …
CGPoint bottomOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentSize.height – self.scrollView.bounds.size.height);
[self.scrollView setContentOffset:bottomOffset animated:NO];
}
– (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
CGPoint bottomOffset = CGPointMake(self.scrollView.contentOffset.x, self.scrollView.contentSize.height – self.scrollView.bounds.size.height);
//設置延遲時間
float scrollDurationInSeconds = 4.0;
//計算timer間隔
float totalScrollAmount = bottomOffset.y;
float timerInterval = scrollDurationInSeconds / totalScrollAmount;
[NSTimer scheduledTimerWithTimeInterval:timerInterval target:self selector:@selector(scrollScrollView:) userInfo:nil repeats:YES];
}
– (void)scrollScrollView:(NSTimer *)timer
{
CGPoint newScrollViewContentOffset = self.scrollView.contentOffset;
//向上移動 1px
newScrollViewContentOffset.y -= 1;
newScrollViewContentOffset.y = MAX(0, newScrollViewContentOffset.y);
//如果到頂瞭，timer中止
if (newScrollViewContentOffset.y == 0) {
[timer invalidate];
}
//最後設置scollView's contentOffset
self.scrollView.contentOffset = newScrollViewContentOffset;
}