iOS开发--UICollectionView网格视图

UICollectionViewFlowLayout: 确定网格视图的布局

上下左右的间距 : sectionInset(left, top, bottom, right)
每一个Cell的大小 : itemSize(width, height)
横向Cell之间的间距 : minimumInteritemSpacing
纵向Cell之间的间距 : minimumLineSpacing

首先：定制Cell#import "CollectionViewCell.h"@implementation CollectionViewCell- (instancetype)initWithFrame:(CGRect)frame{    self = [super initWithFrame:frame];    if (self) {      self.backgroundColor = [UIColor lightGrayColor];        self.imgView = [[UIImageView alloc] initWithFrame:CGRectMake(5, 5, CGRectGetWidth(self.frame)-10, CGRectGetHeight(self.frame)-10)];        self.imgView.backgroundColor = [UIColor groupTableViewBackgroundColor];        [self addSubview:self.imgView];        self.text = [[UILabel alloc] initWithFrame:CGRectMake(5, CGRectGetMaxY(self.imgView.frame)-50, CGRectGetWidth(self.frame)-10, 20)];        self.text.backgroundColor = [UIColor brownColor];        self.text.textAlignment = NSTextAlignmentCenter;        [self addSubview:self.text];        self.btn = [UIButton buttonWithType:UIButtonTypeCustom];        self.btn.frame = CGRectMake(5, CGRectGetMaxY(self.text.frame), CGRectGetWidth(self.frame)-10, 30);        [self.btn setBackgroundColor:[UIColor orangeColor]];        [self.btn setTitle:@"按钮" forState:UIControlStateNormal];        [self addSubview:self.btn];    }    return self;}@end

#define fDeviceWidth [UIScreen mainScreen].bounds.size.width#define fDeviceHeight [UIScreen mainScreen].bounds.size.height#import "JCollectionController.h"#import "CollectionViewCell.h"#import "CustomHeaderView.h"static const float fHeaderHeight = 200.0f;@interface JCollectionController ()<UICollectionViewDataSource,UICollectionViewDelegateFlowLayout>{    CustomHeaderView *_headerView;}@end@implementation JCollectionController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view from its nib.    [self setupCollectionView];}- (void)setupCollectionView{    UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc]init];    [flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];    //头部大小    flowLayout.headerReferenceSize = CGSizeMake(fDeviceWidth, fHeaderHeight);    self.collectionView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 0, fDeviceWidth , fDeviceHeight) collectionViewLayout:flowLayout];    //注册Cell，必须要有 、、、注册ReuseableView---头部（尾部同理）    [self.collectionView registerClass:[CollectionViewCell class] forCellWithReuseIdentifier:@"myCell"];    [self.collectionView registerClass:[UICollectionReusableView class] forSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"ReuseableView"];    self.collectionView.delegate = self;    self.collectionView.dataSource = self;    [self.view addSubview:self.collectionView];    _headerView = [[CustomHeaderView alloc] initWithFrame:CGRectMake(5, 0, fDeviceWidth-10, fHeaderHeight)];    [self.view addSubview:_headerView];}#pragma mark ---UICollectionViewDataSource/** *  UICollectionViewCell的个数 */- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{    return 10;}/** *  section的个数 */- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{    return 2;}/** *  每个UICollectionView展示的内容 */-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{    static NSString * CellIdentifier = @"myCell";    CollectionViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier forIndexPath:indexPath];    if (!cell) {        NSLog(@"----------------");    }    cell.imgView.image = [UIImage imageNamed:@"aaa"];    cell.text.text = [NSString stringWithFormat:@"cell-%ld",indexPath.row];    return cell;}/** *  头部显示的内容 */- (UICollectionReusableView *)collectionView:(UICollectionView *)collectionView viewForSupplementaryElementOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath{    UICollectionReusableView *headerView = [collectionView dequeueReusableSupplementaryViewOfKind:UICollectionElementKindSectionHeader withReuseIdentifier:@"ReuseableView" forIndexPath:indexPath];    [headerView addSubview:_headerView];    return headerView;}#pragma mark --UICollectionViewDelegateFlowLayout/** *  定义每个UICollectionView 的大小 */- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath{    CGFloat spacing = 10.0;    CGFloat itemWidth = (fDeviceWidth - spacing *3)/2.0;    CGFloat itemHeight = itemWidth;    return CGSizeMake(itemWidth,itemHeight);}/** *  定义每个UICollectionView 的 margin */-(UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{    return UIEdgeInsetsMake(10.0, 10.0, 10.0, 10.0);}/** *  定义每个UICollectionView 的横向间距 */- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section{    return 10;}/** *  定义每个UICollectionView 的 竖向间距 */- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section{    return 10;}#pragma mark --UICollectionViewDelegate/** *  UICollectionView被选中时调用的方法 */-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath{    UICollectionViewCell * cell = (UICollectionViewCell *)[collectionView cellForItemAtIndexPath:indexPath];    cell.backgroundColor = [UIColor whiteColor];    NSLog(@"点击：{区%ld,%ld个}宽：%f",indexPath.section,indexPath.row,cell.frame.origin.x);}/** *  返回这个UICollectionView是否可以被选择 */-(BOOL)collectionView:(UICollectionView *)collectionView shouldSelectItemAtIndexPath:(NSIndexPath *)indexPath{    return YES;}@end