UICollectionView 基礎

  UICollectionViewFlowLayout *flowLayout= [[UICollectionViewFlowLayout alloc] init];

     flowLayout.scrollDirection = UICollectionViewScrollDirectionVertical; //滾動方向

     flowLayout.minimumLineSpacing = 10.0 ; //行間距(最小值)

     flowLayout.minimumInteritemSpacing = 50.0 ; //item間距(最小值)

     flowLayout.itemSize = CGSizeMake( 50 , 50 ); //item的大小

     flowLayout.sectionInset = UIEdgeInsetsMake( 10 , 10 , 10 , 10 ); //設置section的邊距

     flowLayout.headerReferenceSize = CGSizeMake( 320 , 20 );

     flowLayout.footerReferenceSize = CGSizeMake( 320 , 20 );

     //第二個參數是cell的佈局

     UICollectionView *collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake( 0 , 0 , 320 , 568 ) collectionViewLayout:flowLayout];

     [flowLayout release];

     collectionView.dataSource = self;

     collectionView.delegate = self;

     collectionView.backgroundColor = [UIColor orangeColor];

     //1 註冊複用cell(cell的類型和標識符)(能夠註冊多個複用cell, 必定要保證重用標示符是不同的)註冊到了collectionView的複用池裏

     [collectionView registerClass:[CLCollectionViewCell class ] forCellWithReuseIdentifier:cellIdentifier];

     

     //第一個參數:返回的View類型

     //第二個參數:設置View的種類(header, footer)

     //第三個參數:設置重用標識符

 　　 [collectionView registerClass:[HeadView class ] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:headerIdentifier];

     [collectionView registerClass:[FootView class ] forSupplementaryViewOfKind:UICollectionElementKindSectionFooter withReuseIdentifier:footerIdentifier];

     [self.view addSubview:collectionView];

 

 

#pragma mark - UICollectionViewDataSource

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView

{

     return 10 ;

}

 

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section

{

     return 10 ;

}

 

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath

{

     //2 從複用池中找cell(1:cell的標示符 2:indexPath決定系統用不用再給你建立cell, 不用建立的話, 就直接使用以前的cell)

     CLCollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];

     cell.backgroundColor = [UIColor yellowColor];

     cell.textLabel.text = [NSString stringWithFormat:@ "%ld" , ( long )indexPath.row];

     return cell;

}

 

- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath

{

     if (kind == UICollectionElementKindSectionHeader) {

         HeadView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:headerIdentifier forIndexPath:indexPath];

         headerView.textLabel.text = @ "讓我組成頭部!" ;

         headerView.textLabel.textAlignment = NSTextAlignmentCenter;

         headerView.textLabel.textColor = [UIColor whiteColor];

         return headerView;

     }

     FootView *footerView = [collectionView dequeueReusableSupplementaryViewOfKind:kind withReuseIdentifier:footerIdentifier forIndexPath:indexPath];

     footerView.textLabel.text = @ "讓我組成尾部!" ;

     footerView.textLabel.textAlignment = NSTextAlignmentCenter;

     footerView.textLabel.textColor = [UIColor whiteColor];

     return footerView;

}

 

#pragma mark - UICollectionViewDelegate

- ( void )collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath

{

     NSLog(@ "%d %d" , indexPath.section, indexPath.row);

}

 

 

#pragma mark - UICollectionViewDelegateFlowLayout

/*

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

{

}

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

{

     

}

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

{

     

}

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

{

     

}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout referenceSizeForHeaderInSection:(NSInteger)section

{

     

}

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout referenceSizeForFooterInSection:(NSInteger)section

{

     

}

  */

 

 

 

 

 

 

 

 

 

 

     [collectionView registerClass:[FootView class ] forSupplementaryViewOfKind:UICollectionElementKindSectionFooter withReuseIdentifier:footerIdentifier];

     [self.view addSubview:collectionView];