UI2_UICollectionViewPicture

//  AppDelegate.m

//  UI2_UICollectionViewPicture

//

//  Created by zhangxueming on 15/7/16.

//  Copyright (c) 2015年 zhangxueming. All rights reserved.

//



#import "AppDelegate.h"

#import "ViewController.h"



@interface AppDelegate ()



@end



@implementation AppDelegate





- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    // Override point for customization after application launch.

    ViewController *root = [[ViewController alloc] init];

    UINavigationController *nav =[[UINavigationController alloc] initWithRootViewController:root];

    self.window.rootViewController = nav;

    self.window.backgroundColor = [UIColor whiteColor];

    

    return YES;

}

 

//  ViewController.h

//  UI2_UICollectionViewPicture

//

//  Created by zhangxueming on 15/7/16.

//  Copyright (c) 2015年 zhangxueming. All rights reserved.

//



#import <UIKit/UIKit.h>



@interface ViewController : UIViewController





@end





//

//  ViewController.m

//  UI2_UICollectionViewPicture

//

//  Created by zhangxueming on 15/7/16.

//  Copyright (c) 2015年 zhangxueming. All rights reserved.

//



#import "ViewController.h"



#define kCellReuseId @"cellID"



@interface ViewController ()<UICollectionViewDataSource, UICollectionViewDelegate>

{

    UICollectionView *_collectionView;

    NSMutableArray *_dataList;

}



@end



@implementation ViewController



- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    //创建数据源

    [self createDataList];

    //创建UI

    [self createUI];

    //代理

    self.navigationController.navigationBar.barTintColor = [UIColor redColor];

}



- (void)createDataList

{

    _dataList = [NSMutableArray array];

    for (int i=0; i<10; i++) {

        NSString *name = [NSString stringWithFormat:@"superCar%i", i];

        NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:@"png"];

        UIImage *image = [UIImage imageWithContentsOfFile:path];

        [_dataList addObject:image];

    }

}



//创建UI



- (void)createUI

{

    //创建布局对象

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

    //上下左右边距

    layout.sectionInset = UIEdgeInsetsMake(10, 10, 10, 10);

    //cell的大小

    layout.itemSize = CGSizeMake(150, 100);

    //cell横向间距

    layout.minimumInteritemSpacing = 20;

    //cell纵向间距

    layout.minimumLineSpacing = 30;

    //创建collectionView

    _collectionView = [[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:layout];

    _collectionView.backgroundColor = [UIColor whiteColor];

    //设置代理

    _collectionView.delegate = self;

    _collectionView.dataSource = self;

    

    //注册cell

    

    [_collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:kCellReuseId];

    

    [self.view addSubview:_collectionView];

}



#pragma mark ---delegate---



//返回分区个数

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView

{

    return 1;

}



//返回分区cell 的个数



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

{

    return _dataList.count;

}



//返回cell



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

{

    UICollectionViewCell *cell  = [collectionView dequeueReusableCellWithReuseIdentifier:kCellReuseId forIndexPath:indexPath];

    

    for (UIView *view in cell.contentView.subviews) {

        [view removeFromSuperview];

    }

    

    UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 150, 100)];

    imageView.image = _dataList[indexPath.item];

    [cell.contentView addSubview:imageView];



    return cell;

}





- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}



@end