• testALAssetsLibrary

  • iOS开发中有时候会经常需要拍照和选取图片,拍照直接调用UIImageViewPicker就可以了,如若要自定义相机的话可以自己定义拍照页面,此先略过不讲。这篇文章只讲述如何自定义相册——利用系统的<AssetsLibrary/AssetsLibrary.h>框架。
  • 首先第一步,当然是要导入<AssetsLibrary/AssetsLibrary.h>框架 -

导入框架

#import <AssetsLibrary/AssetsLibrary.h>
#import <AssetsLibrary/ALAsset.h>
#import <AssetsLibrary/ALAssetsLibrary.h>
#import <AssetsLibrary/ALAssetsGroup.h>
#import <AssetsLibrary/ALAssetRepresentation.h>
  • 循环遍历ALAssetsLibrary,调用enumerateGroupsWithTypes的block。

      [_assetsLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop) {
      if (group)
      {
          //NSLog(@"*****相册个数***%@",self.groupMutArr);
          [self.groupMutArr addObject:group];
          //每个相册的名字
          NSString *groupName = [group valueForProperty:ALAssetsGroupPropertyName];
          [self.groupName addObject:groupName];
            
          for (ALAssetsGroup *_group in self.groupMutArr)
          {
              [_group enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {
                  if (result)
                  {
                      [self.imageArr addObject:result];
                      //NSLog(@"*****所有相册里的所有图片****%@",self.imageArr);
                      //UIImage *image = [UIImage imageWithCGImage: result.thumbnail];
                      //NSString *type=[result valueForProperty:ALAssetPropertyType];
                  }
              }];
          }
      }
        
      [self.collectionView reloadData];
        
      } failureBlock:^(NSError *error) {
      NSLog(@"获取相册失败");
      }];
    
  • 根据数据数组来定义collectionView,返回数组

      pragma mark - UICollectionViewDataSource
      - (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
      {
          NSMutableArray *testMutArr = [NSMutableArray array];
          ALAssetsGroup *testGroup = [self.groupMutArr objectAtIndex:section];
          [testGroup enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {
              if (result)
              {
                  [testMutArr addObject:result];
              }
          }];
            
          return testMutArr.count;
      }
        
      - (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
      {
          return self.groupMutArr.count;
      }
        
      - (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
      {
          YBTNFirstCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:TNFirstCell forIndexPath:indexPath];
            
          NSMutableArray *mutArr = [NSMutableArray array];
          ALAssetsGroup *testGroup = [self.groupMutArr objectAtIndex:indexPath.section];
          [testGroup enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {
              if (result){
                  [mutArr addObject:result];
              }}];
            
          ALAsset *result = [mutArr objectAtIndex:indexPath.item];
          UIImage *image = [UIImage imageWithCGImage: result.thumbnail];
          [cell setCellWithImage:image];
          return cell;
      }
    
  • 项目截图如下: 截图

参考在此项目demo