使用CollectionView做横向滑动分页效果:

一开始几页滑动是没有问题的,等滑到三四个页面之后,就出现奇怪的缝隙,一开始死活找不到原因,最后在layout的代理方法minimumLineSpacingForSectionAtIndex返回值设置为0才解决,一开始想我只显示一行,跟这个应该没什么关系吧,就没设置,其他的两个代理方法minimumInteritemSpacingForSectionAtIndex和insetForSectionAtIndex都返回的是0.最后没辙了,1个晚上过去了,加了一个代理方法,然后问题就奇妙的解决了。

//添加UICollectionView

{

MyBigPictureFlowLayout *layout = [[MyBigPictureFlowLayout alloc] init];

//UICollectionViewFlowLayout *layout = [[UICollectionViewFlowLayout alloc] init];

[layout setScrollDirection:UICollectionViewScrollDirectionHorizontal];

self.albumCollection = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 64, kAllWidth, kAllHeight - 64) collectionViewLayout:layout];

self.albumCollection.backgroundColor = [UIColor clearColor];

self.albumCollection.dataSource = self;

self.albumCollection.delegate = self;

self.albumCollection.pagingEnabled = YES;

self.albumCollection.bounces = YES;

self.albumCollection.showsVerticalScrollIndicator = NO;

self.albumCollection.showsHorizontalScrollIndicator = NO;

self.albumCollection.contentSize = CGSizeMake(kAllWidth*self.dataSource.count, kAllHeight-64);

self.albumCollection.contentOffset = CGPointMake(kAllWidth*(self.index-1), 0);

[vContainer addSubview:self.albumCollection];

//注册cell的视图

static NSString *identifer = @"BigPictureCell";

[self.albumCollection registerClass:[BigPictureCell class] forCellWithReuseIdentifier:identifer];

}

#pragma mark-Delegate的代理方法

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{

return 0;

}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{

return 0;

}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{

return CGSizeMake(kAllWidth, kAllHeight - 64);

}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{

return UIEdgeInsetsMake(0, 0, 0, 0);

}

UICollectionViewFlowLayout的写法:

#import <UIKit/UIKit.h>

@interface MyBigPictureFlowLayout : UICollectionViewFlowLayout

@end

#import "MyBigPictureFlowLayout.h"

@implementation MyBigPictureFlowLayout

-(NSArray *)layoutAttributesForElementsInRect:(CGRect)rect{

NSArray *answer=[[super layoutAttributesForElementsInRect:rect] mutableCopy];

for (int i=1; i<[answer count]; i++) {

UICollectionViewLayoutAttributes *currentLayoutAttributes=answer[i];

UICollectionViewLayoutAttributes *prevLayoutAttributesans=answer[i-1];

NSInteger maximumSpacing=0;

//NSInteger origin=CGRectGetMaxX(prevLayoutAttributesans.frame);

float origin = prevLayoutAttributesans.frame.origin.x + prevLayoutAttributesans.frame.size.width;

CGRect frame=currentLayoutAttributes.frame;

frame.origin.x=origin+maximumSpacing;

currentLayoutAttributes.frame=frame;

}

NSLog(@"%@",answer);

return answer;

}

@end

代码地址:http://git.oschina.net/hyp.cn/demo

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