我正在使用一个项目,我正在使用UICollectionView来创建一个“图像报告器”,我在那里广告一系列标志. collectionView是一个项目高和十二个项目长,一次显示两到三个项目(取决于徽标的大小可见).
我想从第一个项目到最后一个缓慢的自动滚动动画,然后重复.
有没有人能够做这项工作？我可以使滚动工作
[myCollection scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:(myImages.count -1) inSection:0] atScrollPosition:UICollectionViewScrollPositionRight animated:YES];
但这太过分了！
[UIView animateWithDuration:10 delay:2 options:(UIViewAnimationOptionAutoreverse + UIViewAnimationOptionRepeat) animations:^{
[myCollection scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:(myImages.count -1) inSection:0] atScrollPosition:UICollectionViewScrollPositionRight animated:NO];
} completion:nil];
这产生了所需的滚动速度,但是只有最后几个单元格在系列中可见.我怀疑他们(甚至起始的可见细胞)正在出场.
有什么想法吗？
解决方法
你可以尝试这种方法：
@property (nonatomic,assign) CGPoint scrollingPoint,endPoint;
@property (nonatomic,strong) NSTimer *scrollingTimer;
@synthesize scrollingPoint,endPoint;
@synthesize scrollingTimer;
- (void)scrollSlowly {
// Set the point where the scrolling stops.
self.endPoint = CGPointMake(0,300);
// Assuming that you are starting at {0,0} and scrolling along the x-axis.
self.scrollingPoint = CGPointMake(0,0);
// Change the timer interval for speed regulation.
self.scrollingTimer = [NSTimer scheduledTimerWithTimeInterval:0.015 target:self selector:@selector(scrollSlowlyToPoint) userInfo:nil repeats:YES];
}
- (void)scrollSlowlyToPoint {
self.collectionView.contentOffset = self.scrollingPoint;
// Here you have to respond to user interactions or else the scrolling will not stop until it reaches the endPoint.
if (CGPointEqualToPoint(self.scrollingPoint,self.endPoint)) {
[self.scrollingTimer invalidate];
}
// Going one pixel to the right.
self.scrollingPoint = CGPointMake(self.scrollingPoint.x,self.scrollingPoint.y+1);
}
