iOS保存图片到新建相册(iOS Photos)

1.直接保存图片相册中(不需要自己创建新的相簿)

- (void)saveImage2Photo:(UIImage *)img {        UIImageWriteToSavedPhotosAlbum(img, self, @selector(image:didFinishSavingWithError:contextInfo:),nil);}- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo{    if (error == nil) {        NSLog(@"保存成功");    }}

2.保存图片到自己创建相册中

有点复杂。。。这里不进行一些文字的概述，跟分析，直接上代码。

没经验的需要理解一些原理可参考以下两篇文章：

ObjC中国 Photos

Photos 框架实践以及坑(简书上一个兄弟的文章，挺不错)

四步骤进行：

1.授权判断

2.创建图片的请求(保存图片到相机胶卷中)

5.创建相簿请求

4.将刚刚添加到"相机胶卷"中的图片到"自己创建相簿"中请求

定一个全局的相册名字

//定义一个全局变量的相册名字static NSString *photoAssetCollectionName = @"loukitphoto";

判断是否有权限访问相簿

//判断是否有权限访问相簿-(void)phAuthorizationCheck{    /*     PHAuthorizationStatusNotDetermined,     用户还没有做出选择     PHAuthorizationStatusDenied,            用户拒绝当前应用访问相册(用户当初点击了"不允许")     PHAuthorizationStatusAuthorized         用户允许当前应用访问相册(用户当初点击了"好")     PHAuthorizationStatusRestricted,        因为家长控制, 导致应用无法方法相册(跟用户的选择没有关系)     */        // 判断授权状态    PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];    if (status == PHAuthorizationStatusRestricted) {        NSLog(@"无法访问相簿--PHAuthorizationStatusRestricted");    } else if (status == PHAuthorizationStatusDenied) {        NSLog(@"无法访问相簿--PHAuthorizationStatusDenied");    } else if (status == PHAuthorizationStatusAuthorized) {        NSLog(@"可以访问相簿--PHAuthorizationStatusAuthorized");        [self saveImage];    } else if (status == PHAuthorizationStatusNotDetermined) {        // 弹框请求用户授权        NSLog(@"第一次访问--PHAuthorizationStatusNotDetermined");        [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {            if (status == PHAuthorizationStatusAuthorized) { // 用户点击了好                [self saveImage];            }        }];    }}

获取相簿(没有就创建，有就用)

//  获得相簿-(PHAssetCollection *)createAssetCollection{        //判断是否已存在    PHFetchResult<PHAssetCollection *> *assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];    for (PHAssetCollection * assetCollection in assetCollections) {        if ([assetCollection.localizedTitle isEqualToString:photoAssetCollectionName]) {            //说明已经有哪对象了            return assetCollection;        }    }        //创建新的相簿    __block NSString *assetCollectionLocalIdentifier = nil;    NSError *error = nil;    //同步方法    [[PHPhotoLibrary sharedPhotoLibrary]performChangesAndWait:^{        // 创建相簿的请求        assetCollectionLocalIdentifier = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:photoAssetCollectionName].placeholderForCreatedAssetCollection.localIdentifier;    } error:&error];        if (error)return nil;        return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[assetCollectionLocalIdentifier] options:nil].lastObject;}

保存图片

//保存图片-(void)saveImage{        __block  NSString *assetLocalIdentifier;    [[PHPhotoLibrary sharedPhotoLibrary]performChanges:^{                //1.保存图片到相机胶卷中----创建图片的请求        assetLocalIdentifier = [PHAssetCreationRequest creationRequestForAssetFromImage:self.imageView.image].placeholderForCreatedAsset.localIdentifier;    } completionHandler:^(BOOL success, NSError * _Nullable error) {        if(success == NO){            NSLog(@"保存图片失败----(创建图片的请求)");            return ;        }                // 2.获得相簿        PHAssetCollection *createdAssetCollection = [self createAssetCollection];        if (createdAssetCollection == nil) {            NSLog(@"保存图片成功----(创建相簿失败!)");            return;        }                // 3.将刚刚添加到"相机胶卷"中的图片到"自己创建相簿"中        [[PHPhotoLibrary sharedPhotoLibrary]performChanges:^{                        //获得图片            PHAsset *asset = [PHAsset fetchAssetsWithLocalIdentifiers:@[assetLocalIdentifier] options:nil].lastObject;            //添加图片到相簿中的请求            PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:createdAssetCollection];            // 添加图片到相簿            [request addAssets:@[asset]];        } completionHandler:^(BOOL success, NSError * _Nullable error) {            if(success){                NSLog(@"保存图片到创建的相簿成功");            }else{                NSLog(@"保存图片到创建的相簿失败");            }        }];    }];}