IOS 将图片保存相册,以及自定义相册关联

1.请求访问权限 2.保存图片到默认相册 3.新建自定义相册,首先进行判断是否有相册 4.将默认相册中保存的图片进行引用到自定义相册中.

若是只是保存图片到默认相册,3,4能够不作.

- (IBAction)save {
    PHAuthorizationStatus oldStatus = [PHPhotoLibrary authorizationStatus];
    
    // 请求\检查访问权限 :
    // 若是用户尚未作出选择，会自动弹框，用户对弹框作出选择后，才会调用block
    // 若是以前已经作过选择，会直接执行block
    [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
        dispatch_async(dispatch_get_main_queue(), ^{
            if (status == PHAuthorizationStatusDenied) { // 用户拒绝当前App访问相册
                if (oldStatus != PHAuthorizationStatusNotDetermined) {
                    XMGLog(@"提醒用户打开开关")
                }
            } else if (status == PHAuthorizationStatusAuthorized) { // 用户容许当前App访问相册
                [self saveImageIntoAlbum];
            } else if (status == PHAuthorizationStatusRestricted) { // 没法访问相册
                [SVProgressHUD showErrorWithStatus:@"因系统缘由，没法访问相册！"];
            }
        });
    }];
}

//保存图片到默认相册

- (PHFetchResult<PHAsset *> *)createdAssets
{
     NSError *error = nil;
    __block NSString *assetID = nil;
    
    // 保存图片到【相机胶卷】
    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
        assetID = [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image].placeholderForCreatedAsset.localIdentifier;
    } error:&error];
    
    if (error) return nil;
    
    // 获取刚才保存的相片
    return [PHAsset fetchAssetsWithLocalIdentifiers:@[assetID] options:nil];
}

/**
 *  保存图片到相册
 */
- (void)saveImageIntoAlbum
{
    // 得到相片
    PHFetchResult<PHAsset *> *createdAssets = self.createdAssets;
    if (createdAssets == nil) {
        [SVProgressHUD showErrorWithStatus:@"保存图片失败！"];
        return;
    }
    
    // 得到相册
    PHAssetCollection *createdCollection = self.createdCollection;
    if (createdCollection == nil) {
        [SVProgressHUD showErrorWithStatus:@"建立或者获取相册失败！"];
        return;
    }
    
    // 添加刚才保存的图片到【自定义相册】
    NSError *error = nil;
    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
        PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:createdCollection];
        [request insertAssets:createdAssets atIndexes:[NSIndexSet indexSetWithIndex:0]];
    } error:&error];
    
    // 最后的判断
    if (error) {
        [SVProgressHUD showErrorWithStatus:@"保存图片失败！"];
    } else {
        [SVProgressHUD showSuccessWithStatus:@"保存图片成功！"];
    }
}

#pragma mark - 得到当前App对应的自定义相册
- (PHAssetCollection *)createdCollection
{
    // 得到软件名字
    NSString *title = [NSBundle mainBundle].infoDictionary[(__bridge NSString *)kCFBundleNameKey];
    
    // 抓取全部的自定义相册
    PHFetchResult<PHAssetCollection *> *collections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
    
    // 查找当前App对应的自定义相册
    for (PHAssetCollection *collection in collections) {
        if ([collection.localizedTitle isEqualToString:title]) {
            return collection;
        }
    }
    
    /** 当前App对应的自定义相册没有被建立过 **/
    // 建立一个【自定义相册】
    NSError *error = nil;
    __block NSString *createdCollectionID = nil;
    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
        createdCollectionID = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:title].placeholderForCreatedAssetCollection.localIdentifier;
    } error:&error];
    
    if (error) return nil;
    
    // 根据惟一标识得到刚才建立的相册
    return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[createdCollectionID] options:nil].firstObject;
}