实现多选相册的图片 demo

1.首先准备3个图片

#import <UIKit/UIKit.h>

typedef void(^SelectBtnClickBlock) (BOOL isSelect);

@interface PhoCollectionViewCell : UICollectionViewCell

@PRoperty (weak ,nonatomic) IBOutlet UIImageView * imageView;

@property (weak ,nonatomic) IBOutlet UIImageView * selectImageView;

@property (nonatomic,copy) SelectBtnClickBlock selectBtnClickBlock;

- (IBAction)selectBtnClick:(id)sender; @property (weak, nonatomic) IBOutlet UIButton *selectBtn;

@end

#import "PhoCollectionViewCell.h"

@implementation PhoCollectionViewCell

- (void)awakeFromNib {
    // Initialization code

}

- (IBAction)selectBtnClick:(id)sender {
    UIButton *btn=(UIButton *)sender;
     btn.selected=!btn.selected;
    NSLog(@"%@",@"aaaa");
      _selectBtnClickBlock(btn.selected);
}
@end

3.创建相片Model

#import <Foundation/Foundation.h>
#import <AssetsLibrary/ALAssetsLibrary.h>

@interface PhoModel : NSObject

@property(nonatomic,strong) ALAsset *asset;
@property (nonatomic,assign) BOOL isSelected;
@end

#import "PhoModel.h"

@implementation PhoModel

@end

4.获取相册图片显示图片

#import "ViewController.h"
#import <AssetsLibrary/AssetsLibrary.h>

#import "AppDelegate.h"
#import "PhoModel.h"
#import "PhoCollectionViewCell.h"

#define applicationDelegate ((AppDelegate *)[UIApplication sharedApplication].delegate)

static NSInteger count = 0;

@interface ViewController ()
{
    NSMutableArray *mutableAssets;
}
@property (weak, nonatomic) IBOutlet UICollectionView *collectionView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    //获取相册中的全部照片
    [self getAllPictures];
    [_collectionView registerNib: [UINib nibWithNibName:@"PhoCollectionViewCell" bundle:nil] forCellWithReuseIdentifier:@"CollectionViewCell"];
}

//获取相册中的全部照片
-(void)getAllPictures {
    mutableAssets = [[NSMutableArray alloc]init];

    NSMutableArray *assetURLDictionaries = [[NSMutableArray alloc] init];
    NSMutableArray *assetGroups = [[NSMutableArray alloc] init];

    __block NSMutableArray *tempMutableAssets = mutableAssets;
    __block ViewController *tempSelf = self;
    __block NSMutableArray *tempAssetGroups = assetGroups;

    [ApplicationDelegate.library enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos usingBlock:^(ALAssetsGroup *group, BOOL *stop){
        if (group != nil) {
            count = [group numberOfAssets];
            __block int groupNum = 0;
            [group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop){
                if(asset != nil) {
                    ++ groupNum;
                    if([[asset valueForProperty:ALAssetPropertyType] isEqualToString:ALAssetTypePhoto]) {
                        [assetURLDictionaries addObject:[asset valueForProperty:ALAssetPropertyURLs]];
                        NSURL *url= (NSURL*) [[asset defaultRepresentation]url];
                        NSLog(@"%@,%@",[asset valueForProperty:ALAssetPropertyDate],url);

//                        [UIImage imageWithCGImage:[[result defaultRepresentation] fullScreenImage]];//图片
//                        [UIImage imageWithCGImage:[result thumbnail]];    //缩略图

                        PhoModel *phoModel=[[PhoModel alloc]init];
                        phoModel.asset=asset;
                        phoModel.isSelected=NO;
                        [tempMutableAssets addObject:phoModel];
                        if (tempMutableAssets.count == groupNum) {
                            [tempSelf allPhotosCollected:tempMutableAssets];
                        }
                    }
                }
            }];
            [tempAssetGroups addObject:group];
        }
    }failureBlock:^(NSError *error){
        NSLog(@"There is an error");
    }];
}

//所有asset
-(void)allPhotosCollected:(NSMutableArray *)mutableAsset{
    [self.collectionView reloadData];
}

#pragma mark -- UICollectionViewDataSource

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    CGSize itemSize = CGSizeMake(([UIScreen mainScreen].bounds.size.width-15)/4.0, ([UIScreen mainScreen].bounds.size.width-30)/4.0);
    return itemSize;
}

//定义展示的UICollectionViewCell的个数
-(NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
    return mutableAssets.count+1;
}
//每个UICollectionView展示的内容
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString * CellIdentifier = @"CollectionViewCell";
    PhoCollectionViewCell * cell = [collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier forIndexPath:indexPath];
    if (indexPath.row==0) {
        cell.imageView.image = [UIImage imageNamed:@"0.png"];
        cell.selectImageView.hidden=YES;
        cell.selectBtnClickBlock=^(BOOL isSelect)
        {
            NSLog(@"cell1 block");
        };
        return cell;
    }

    PhoModel *phoModel = mutableAssets[indexPath.row-1];

    cell.imageView.image = [UIImage imageWithCGImage:[phoModel.asset thumbnail]];

    if (phoModel.isSelected) {
        cell.selectImageView.image=[UIImage imageNamed:@"2.png"];
    }
    else
    {
        cell.selectImageView.image=[UIImage imageNamed:@"1.png"];
    }
    cell.selectImageView.hidden=NO;
    cell.selectBtn.selected=phoModel.isSelected;
    cell.selectBtnClickBlock=^(BOOL isSelect)
    {
        //单选多选标记 false 单选 true 多选
        BOOL issangal=false;
        if (issangal) {
            for (PhoModel *tmpPhotoModel in mutableAssets) {
                tmpPhotoModel.isSelected = NO;
            }
        }
        phoModel.isSelected=isSelect;
        [_collectionView reloadData];
    };

    return cell;
}
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
    NSLog(@"%ld",indexPath.row);
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

5.效果