iOS UI基礎-19.0 UICollectionView

直接上代碼，說明請看註釋吧

1.繼承三個代理 UICollectionViewDataSource,UICollectionViewDelegate,UICollectionViewDelegateFlowLayout

2.直接看代碼

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    //肯定是水平滾動，仍是垂直滾動
    UICollectionViewFlowLayout *flowLayout=[[UICollectionViewFlowLayout alloc] init];
    [flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];
   // 能夠不使用flowLayout 代理，直接像下面這樣給值
    //[flowLayout setMinimumLineSpacing:0]; // 底部空白清空
    //[flowLayout setMinimumInteritemSpacing:0]; // 左右空白清空
    //flowLayout.sectionInset = UIEdgeInsetsMake(0, 0, 8, 0); // 定義每一個的margin
        
    self.collectionView=[[UICollectionView alloc] initWithFrame:CGRectMake(0, 64, 320, 200) collectionViewLayout:flowLayout];
    self.collectionView.dataSource=self;
    self.collectionView.delegate=self;
    [self.collectionView setBackgroundColor:[UIColor clearColor]];
    
    //註冊Cell，必需要有
    [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"UICollectionViewCell"];
    
    [self.view addSubview:self.collectionView];
}


#pragma mark -- UICollectionViewDataSource

//定義展現的UICollectionViewCell的個數
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    return 10;
}

//定義展現的Section的個數
-(NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
    return 2;
}

//每一個UICollectionView展現的內容
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString * CellIdentifier = @"UICollectionViewCell";
    UICollectionViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier forIndexPath:indexPath];
    
    cell.backgroundColor = [UIColor colorWithRed:((10 * indexPath.row) / 255.0) green:((20 * indexPath.row)/255.0) blue:((30 * indexPath.row)/255.0) alpha:1.0f];
    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 20, 20)];
    label.textColor = [UIColor redColor];
    label.text = [NSString stringWithFormat:@"%d",indexPath.row];
 
    for (id subView in cell.contentView.subviews) {
        [subView removeFromSuperview];
    }
    [cell.contentView addSubview:label];
    return cell;
}

#pragma mark --UICollectionViewDelegateFlowLayout

//定義每一個Item 的大小
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
    return CGSizeMake(60, 60);
}

//定義每一個UICollectionView 的 margin
-(UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section
{
    return UIEdgeInsetsMake(5, 5, 5, 5);
}

#pragma mark --UICollectionViewDelegate

//UICollectionView被選中時調用的方法
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    UICollectionViewCell * cell = (UICollectionViewCell *)[collectionView cellForItemAtIndexPath:indexPath];
    //臨時改變個顏色，看好，只是臨時改變的。若是要永久改變，能夠先改數據源，而後在cellForItemAtIndexPath中控制。（和UITableView差很少吧！O(∩_∩)O~）
    cell.backgroundColor = [UIColor greenColor];
    NSLog(@"item======%d",indexPath.item);
    NSLog(@"row=======%d",indexPath.row);
    NSLog(@"section===%d",indexPath.section);
}

//返回這個UICollectionView是否能夠被選擇
-(BOOL)collectionView:(UICollectionView *)collectionView shouldSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}

@end

快捷頭部

        //定義每一個UICollectionView 的大小
        flowLayout.itemSize = CGSizeMake((fDeviceWidth-20)/2, (fDeviceWidth-20)/2+50);
        //定義每一個UICollectionView 橫向的間距
        flowLayout.minimumLineSpacing = 5;
        //定義每一個UICollectionView 縱向的間距
        flowLayout.minimumInteritemSpacing = 0;
        //定義每一個UICollectionView 的邊距距
        flowLayout.sectionInset = UIEdgeInsetsMake(0, 5, 5, 5);//上左下右

 

參考博客：http://blog.csdn.net/u011439689/article/details/39551163?utm_source=tuicool&utm_medium=referral