UICollectionView的知识点
#pragma mark - UICollectionViewDelegateFlowLayout
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.section == 0 || indexPath.section == 1) {
return CGSizeMake(SCREEN_WIDTH, 80);
} else if (indexPath.section == 2) {
return CGSizeMake(SCREEN_WIDTH / 3 - 15, 200);
} else if (indexPath.section == 3) {
return CGSizeMake(SCREEN_WIDTH / 2 - 25, 100);
} else {
return CGSizeMake(SCREEN_WIDTH, 250);
}
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{
if (section == 2) {
return UIEdgeInsetsMake(5, 5, 5, 5);
} else if (section == 3) {
return UIEdgeInsetsMake(10, 10, 10, 10);
} else {
return UIEdgeInsetsMake(0, 0, 0, 0);
}
}
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section {
if (section == 0) {
return CGSizeMake(SCREEN_WIDTH, 1);
} else if (section == 1) {
return CGSizeMake(SCREEN_WIDTH, 15);
} else {
return CGSizeMake(SCREEN_WIDTH, 45);
}
}
#pragma mark - UICollectionViewDataSource
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
if (section == 0 || section == 1) {
return 1;
} else if (section == 2) {
return 3;
} else if (section == 3) {
return 4;
} else {
return 2;
}
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.section == 0 || indexPath.section == 1) {
CustomCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"customCell" forIndexPath:indexPath];
NSDictionary *dic = _customArr[indexPath.section];
cell.titleLabel.text = dic[@"title"];
cell.subTitleLabel.text = dic[@"sub"];
cell.picImageView.image = [UIImage imageNamed:dic[@"image"]];
return cell;
} else if (indexPath.section == 2) {
SceneCollectionCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"sceneCollection" forIndexPath:indexPath];
// 本地数据
SceneModel *scene = _sceneArr[indexPath.row];
cell.sceneLabel.text = scene.journeyName;
[cell.sceneImage sd_setImageWithURL:[NSURL URLWithString:scene.imageUrl] placeholderImage:[UIImage imageNamed:@"baobao"]];
[cell.userImage sd_setImageWithURL:[NSURL URLWithString:scene.userAvatar] placeholderImage:[UIImage imageNamed:@"baobao"]];
return cell;
} else if (indexPath.section == 3){
SelectionCollectionCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"selectionCollection" forIndexPath:indexPath];
SelectModel *select = _selectionArr[indexPath.row];
cell.selectLabel.text = select.title;
[cell.selectPic sd_setImageWithURL:[NSURL URLWithString:select.imageUrl] placeholderImage:[UIImage imageNamed:@"baobao"]];
return cell;
} else {
DigestCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"DigestCell" forIndexPath:indexPath];
TravelModel *travel = _travelArr[indexPath.row];
cell.digestTitleL.text = travel.title;
cell.digestSubTitleL.text = travel.subTitle;
cell.digestSeeCountL.text = travel.follow;
cell.digestTimeL.text = travel.date;
[cell.disgestBackImg sd_setImageWithURL:[NSURL URLWithString:travel.imageUrl] placeholderImage:[UIImage imageNamed:@"baobao"]];
return cell;
}
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
return 5;
}
下面这个方法是用来处理分区的,如果返回nil或者0程序会崩溃.很重要!!!
//返回对应section里 头UICollectionReusableView和脚View
- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath {
if (indexPath.section == 0 || indexPath.section == 1) {
FindDivisionReusableView *reusableView = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:@"FindDivisionReusableView" forIndexPath:indexPath];
if (indexPath.section == 0) {
reusableView.hidden = YES;
return reusableView;
} else {
return reusableView;
}
} else {
FindCollectionReusableView *reusableView = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:@"FindCollectionReusableView" forIndexPath:indexPath];
reusableView.sectionLabel.text = _sectionArr[indexPath.section - 2];
return reusableView;
}
}
#pragma mark - UICollectionViewDelegate
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.section == 0) {
RouteViewController *routeVc = [[RouteViewController alloc] initWithNibName:NSStringFromClass([RouteViewController class]) bundle:nil];
[self.navigationController pushViewController:routeVc animated:YES];
} else if (indexPath.section == 1){
} else if (indexPath.section == 2){
} else if (indexPath.section == 3) {
} else {
}
}
