我在滾動視圖中有一個問題。如何在UIScrollView中自定義分頁?
現在我寫了一個關於圖片庫與滾動視圖的示例。我有大量的圖像添加到滾動視圖。每次顯示3張圖像,問題是如何正確測量滾動。例如:每個滾動的最小值正在移動1個圖像。現在,我認爲每次滾動時,移動的最小圖像都是3.這使我不能停在我想看到的正確圖像上。 以下是代碼。
- (void)layoutScrollImages
{
UIImageView *view = nil;
NSArray *subviews = [scroll subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIImageView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
[scroll setContentSize:CGSizeMake((kNumImages * kScrollObjWidth), [scroll bounds].size.height)];
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
// 1. setup the scrollview for multiple images and add it to the view controller
//
// note: the following can be done in Interface Builder, but we show this in code for clarity
[scroll setBackgroundColor:[UIColor blackColor]];
[scroll setCanCancelContentTouches:NO];
scroll.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scroll.clipsToBounds = YES; // default is NO, we want to restrict drawing within our scrollview
scroll.scrollEnabled = YES;
// pagingEnabled property default is NO, if set the scroller will stop or snap at each photo
// if you want free-flowing scroll, don't set this property.
scroll.pagingEnabled = YES;
// load all the images from our bundle and add them to the scroll view
NSUInteger i;
for (i = 1; i <= kNumImages; i++)
{
NSString *imageName = [NSString stringWithFormat:@"image%d.jpg", i];
UIImage *image = [UIImage imageNamed:imageName];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect rect = imageView.frame;
rect.size.height = kScrollObjHeight;
rect.size.width = kScrollObjWidth;
imageView.frame = rect;
imageView.tag = i; // tag our images for later use when we place them in serial fashion
[scroll addSubview:imageView];
[imageView release];
}
[self layoutScrollImages];
}