项目中为了方便查看保存的图片，需要把图片保存到自定义的相册中，具体代码如下：
1、先检查相册权限
- (void)saveImageToAlbumWithName:(NSString *)albumName image:(UIImage *)image {
//判断授权状态
PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
if (status == PHAuthorizationStatusAuthorized) { //已授权
[self saveImageWithImage:image albumName:albumName];
} else if (status == PHAuthorizationStatusDenied) { //拒绝
NSLog(@"请打开访问相册的权限");
} else if (status == PHAuthorizationStatusNotDetermined) { //未决定
// 弹框请求用户授权
[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
if (status == PHAuthorizationStatusAuthorized) { // 用户点击了好
[self saveImageWithImage:image albumName:albumName];
}
}];
} else if (status == PHAuthorizationStatusRestricted) { //家长控制模式限制
NSLog(@"因为系统原因, 无法访问相册");
}
}
2、创建自定义相册
- (PHAssetCollection *)creatPHAssetWithAlbumName:(NSString *)albumName {
//从已经存在的相簿中查找应用对应的相册
PHFetchResult<PHAssetCollection *> *assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
for (PHAssetCollection *collection in assetCollections) {
if ([collection.localizedTitle isEqualToString:albumName]) {
return collection;
}
}
// 没找到，就创建新的相簿
NSError *error;
__block NSString *assetCollectionLocalIdentifier = nil;
//这里用wait请求，保证创建成功相册后才保存进去
[[PHPhotoLibrary sharedPhotoLibrary]performChangesAndWait:^{
assetCollectionLocalIdentifier = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:albumName].placeholderForCreatedAssetCollection.localIdentifier;
} error:&error];
if (error) return nil;
return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[assetCollectionLocalIdentifier] options:nil].lastObject;
}
3、保存图片
- (void)saveImageWithImage:(UIImage *)image albumName:(NSString *)albumName {
// PHAsset : 一个资源，一个图片
// PHAssetCollection : 一个相簿 （也可以说是一个相册）
// PHotoLibrary 整个照片库（里面会有很多相册）
__block NSString *assetLocalIdentifier = nil;
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
// 1.保存图片到相机胶卷中
assetLocalIdentifier = [PHAssetChangeRequest creationRequestForAssetFromImage:image].placeholderForCreatedAsset.localIdentifier;
} completionHandler:^(BOOL success, NSError * _Nullable error) {
if (success == NO || error) {
dispatch_async(dispatch_get_main_queue(), ^{
NSLog(@"保存照片失败");
});
return;
}
// 2. 获得相册
PHAssetCollection *creatAssetCollction = [self creatPHAssetWithAlbumName:albumName];
if (creatAssetCollction == nil) {
dispatch_async(dispatch_get_main_queue(), ^{
NSLog(@"创建相册失败");
});
return;
}
//创建成功，就把图片保存到相册中
[[PHPhotoLibrary sharedPhotoLibrary]performChanges:^{
//添加相机胶卷中的图片到相簿中去
PHAsset *asset = [PHAsset fetchAssetsWithLocalIdentifiers:@[assetLocalIdentifier] options:nil].lastObject;
//添加图片到相册中的请求
PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:creatAssetCollction];
[request addAssets:@[asset]];
} completionHandler:^(BOOL success, NSError * _Nullable error) {
if (success == NO || error) {
dispatch_async(dispatch_get_main_queue(), ^{
NSLog("保存图片失败");
});
} else {
dispatch_async(dispatch_get_main_queue(), ^{
NSLog(@"保存图片成功");
});
}
}];
}];
}
