厦门好的网站设计,百度营销是什么,wordpress 文章阅读次数,广州天河区是富人区吗个人觉得 collection view 做轮播是最方便的#xff0c;设置下flowlayout 其他不会有很大的变动#xff0c;没有什么逻辑的代码 lets begin…… 创建自定义的view .h 声明文件 interface CollectionViewShuffling : UIViewproperty (nonatomic,strong)NSArray *array;end .m …个人觉得 collection view 做轮播是最方便的设置下flowlayout 其他不会有很大的变动没有什么逻辑的代码 lets begin…… 创建自定义的view .h 声明文件 interface CollectionViewShuffling : UIViewproperty (nonatomic,strong)NSArray *array;end .m 实现文件 interface CollectionViewShuffling ()UICollectionViewDelegate, UICollectionViewDataSourceproperty (nonatomic,strong)UICollectionView *collectionView;
property (nonatomic,strong)NSMutableArray *collectionArray;endimplementation CollectionViewShuffling
synthesize array _array;-(instancetype)initWithFrame:(CGRect)frame{if (self [super initWithFrame:frame]) {}return self;
}
/**这个是横向滚动轮播的重点研究对象*/
-( UICollectionViewFlowLayout *)creatFlowLayout{// 创建UICollectionViewFlowLayout约束对象UICollectionViewFlowLayout *flowLayout [[UICollectionViewFlowLayout alloc] init];// 设置item的Size大小flowLayout.itemSize CGSizeMake(self.frame.size.width, self.frame.size.height);// 设置uicollection 的 横向滑动flowLayout.scrollDirection UICollectionViewScrollDirectionHorizontal;flowLayout.minimumLineSpacing 0;return flowLayout;
}- (UICollectionView *)collectionView
{if (!_collectionView) {UICollectionViewFlowLayout *flowLayout [self creatFlowLayout];_collectionView [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height) collectionViewLayout:flowLayout];[self addSubview:_collectionView];// 设置代理_collectionView.delegate self;_collectionView.dataSource self;
// _collectionView.showsHorizontalScrollIndicator NO;// 设置不展示滑动条_collectionView.pagingEnabled YES; // 设置整页滑动// 设置当前collectionView 到哪个位置(indexPath row 0 section 取中间(50个))[_collectionView registerNib:[UINib nibWithNibName:ShufflingItem bundle:nil] forCellWithReuseIdentifier:ShufflingItem];}return _collectionView;
}-(void)setArray:(NSArray *)array{NSAssert(array.count ! 0, 传入的滚动数组是 空的);_array array;[self prepareData];[self prepareUI];
}-(void)prepareUI{[self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:1 inSection:0] atScrollPosition:UICollectionViewScrollPositionLeft animated:false];[self.collectionView reloadData];
}- (void)prepareData{self.collectionArray [NSMutableArray new];// 首位 添加数组最后的元素[self.collectionArray addObject:_array.lastObject];// 添加数组元素[self.collectionArray addObjectsFromArray:_array];// 末尾 补充第一个元素[self.collectionArray addObject:_array.firstObject];
}
/*collection view delegate*/
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{return 1;
}
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{return self.collectionArray.count;
}- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{ShufflingItem *item [collectionView dequeueReusableCellWithReuseIdentifier:ShufflingItem forIndexPath:indexPath];if (!item) {item [[ShufflingItem alloc] init];}item.imageView.backgroundColor self.collectionArray[indexPath.row];return item;
}-(void)scrollViewDidScroll:(UIScrollView *)scrollView{if (scrollView self.collectionView) {NSLog(scroll content %,NSStringFromCGPoint(scrollView.contentOffset));//检测移动的位移if (scrollView.contentOffset.x (self.collectionArray.count-1)*(self.frame.size.width) ) {[self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:1 inSection:0] atScrollPosition:UICollectionViewScrollPositionLeft animated:false];}else if (scrollView.contentOffset.x 0){[self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForItem:(self.collectionArray.count-2) inSection:0] atScrollPosition:UICollectionViewScrollPositionLeft animated:false];}else{// 正常滚动}}
} 最简单的collection 轮播实现啦…… 总结下他的实现为什么如此简单 collection view 有个flow layout 设置这个属性就可以让他横向滚动竖向滚动还有一个重点 声明下 collection view 使用 item cell 的时候是必须注册的调用方法 -(void)prepareCollectShuffling{CollectionViewShuffling *collectShuffling [[CollectionViewShuffling alloc]initWithFrame:CGRectMake(10, 320, self.view.frame.size.width -20, 220)];[self.view addSubview:collectShuffling];;collectShuffling.array self.arr;
} 这个写完距离成功又进了一步继续………………转载于:https://www.cnblogs.com/Bob-blogs/p/6773070.html
