改良UIScrollView滚动视图

#define HEIGHT  self.view.frame.size.height

#define WIDTH    self.view.frame.size.width

@interface ViewController : UIViewController<UIScrollViewDelegate>

@property (strong,nonatomic) UIScrollView *myScorolV;

@property (strong,nonatomic) UIPageControl *pageC;

@property (strong,nonatomic) NSMutableArray *arrPage;

@property (strong,nonatomic) UIImageView *threeImage;

@property (strong,nonatomic) UIImageView *secondImage;

@property (strong,nonatomic) UIImageView *firstImage;

@property (assign,nonatomic) int currentPage;

@end

//滚动视图创建

self.myScorolV = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, WIDTH, HEIGHT)];

self.myScorolV.contentSize = CGSizeMake(WIDTH * 3, 0);

self.myScorolV.pagingEnabled = YES;

self.myScorolV.showsHorizontalScrollIndicator = NO;

self.myScorolV.delegate = self;

[self.view addSubview:self.myScorolV];

//分页视图

self.pageC = [[UIPageControl alloc] initWithFrame:CGRectMake(WIDTH / 5 * 2, HEIGHT - 80, WIDTH / 5, 40)];

self.pageC.backgroundColor = [UIColor clearColor];

self.pageC.currentPage = 0;

self.pageC.numberOfPages = 5;

//指定页码颜色

self.pageC.currentPageIndicatorTintColor = [UIColor redColor];

self.pageC.pageIndicatorTintColor = [UIColor greenColor];

[self.view addSubview:self.pageC];

self.arrPage = [NSMutableArray arrayWithCapacity:10];

for (int i = 1; i < 6; i++)

{

UIImage *image = [UIImage imageNamed:[NSString stringWithFormat:@"%d.png",i]];

[self.arrPage addObject:image];

}

self.firstImage = [[UIImageView alloc] init];

self.secondImage = [[UIImageView alloc] init];

self.threeImage = [[UIImageView alloc] init];

self.currentPage = 0;

[self relodeImage];

}

-(void)relodeImage

{

if (self.currentPage == 0)

{

self.firstImage.image = [self.arrPage lastObject];

self.secondImage.image = [self.arrPage objectAtIndex:self.currentPage];

self.threeImage.image = [self.arrPage objectAtIndex:self.currentPage + 1];

}

else if (self.currentPage == self.arrPage.count - 1)

{

self.firstImage.image = [self.arrPage objectAtIndex:self.currentPage - 1];

self.secondImage.image = [self.arrPage objectAtIndex:self.currentPage];

self.threeImage.image = [self.arrPage objectAtIndex:0];

}

else

{

self.firstImage.image = [self.arrPage objectAtIndex:self.currentPage - 1];

self.secondImage.image = [self.arrPage objectAtIndex:self.currentPage];

self.threeImage.image = [self.arrPage objectAtIndex:self.currentPage + 1];

}

self.firstImage.frame = CGRectMake(0, 0, WIDTH, HEIGHT);

self.secondImage.frame = CGRectMake(WIDTH, 0, WIDTH, HEIGHT);

self.threeImage.frame = CGRectMake(WIDTH * 2, 0, WIDTH, HEIGHT);

[self.myScorolV addSubview:self.firstImage];

[self.myScorolV addSubview:self.secondImage];

[self.myScorolV addSubview:self.threeImage];

self.myScorolV.contentOffset = CGPointMake(WIDTH, 0);

}

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView

{

int number = (int)self.myScorolV.contentOffset.x;

if (number < 0 || number == 0)

{

if (self.currentPage == 0)

{

self.currentPage = (int)(self.arrPage.count - 1);

}

else

{

self.currentPage--;

}

}

else if (number > WIDTH * 2 || number == WIDTH * 2)

{

if (self.currentPage == (int)self.arrPage.count - 1)

{

self.currentPage = 0;

}

else

{

self.currentPage++;

}

}

self.pageC.currentPage = self.currentPage;

[self relodeImage];

}