ios 如何将图片保存至自定义分组

一般我们照片存储都是直接存储在相机胶卷中，调用下面的方法就可以了：

void UIImageWriteToSavedPhotosAlbum (
UIImage *image,
id completionTarget,
SEL completionSelector,
void *contextInfo
);

       但是如果我们想将图片存储到自定义的分组该怎么做呢，我查了一下ALAssetsLibrary的文档，发现没有相应的方法，好吧，google一下，发现了一篇文章：点击打开链接。

       作者的解决思路如下：

1.将图片先保存到相机胶卷中；

2.在相机胶卷中找到这个图片所创建的AlAsset；

3.将此AlAsset添加到你需要存放的自定义分组中。

 

      主要代码如下所示，注释也很清楚了：

保存照片至相册：

-(void)saveImage:(UIImage*)image toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock
{
//write the image data to the assets library (camera roll)
[self writeImageToSavedPhotosAlbum:image.CGImage orientation:(ALAssetOrientation)image.imageOrientation
completionBlock:^(NSURL* assetURL, NSError* error) {

//error handling
if (error!=nil) {
completionBlock(error);
return;
}

//add the asset to the custom photo album
[self addAssetURL: assetURL
toAlbum:albumName
withCompletionBlock:completionBlock];

}];
}

增加图片至自定义相册：

-(void)addAssetURL:(NSURL*)assetURL toAlbum:(NSString*)albumName withCompletionBlock:(SaveImageCompletion)completionBlock
{
__block BOOL albumWasFound = NO;

//search all photo albums in the library
[self enumerateGroupsWithTypes:ALAssetsGroupAlbum
usingBlock:^(ALAssetsGroup *group, BOOL *stop) {

//compare the names of the albums
if ([albumName compare: [group valueForProperty:ALAssetsGroupPropertyName]]==NSOrderedSame) {

//target album is found
albumWasFound = YES;

//get a hold of the photo's asset instance
[self assetForURL: assetURL
resultBlock:^(ALAsset *asset) {

//add photo to the target album
[group addAsset: asset];

//run the completion block
completionBlock(nil);

} failureBlock: completionBlock];

//album was found, bail out of the method
return;
}

if (group==nil && albumWasFound==NO) {
//photo albums are over, target album does not exist, thus create it

__weak ALAssetsLibrary* weakSelf = self;

//create new assets album
[self addAssetsGroupAlbumWithName:albumName
resultBlock:^(ALAssetsGroup *group) {

//get the photo's instance
[weakSelf assetForURL: assetURL
resultBlock:^(ALAsset *asset) {

//add photo to the newly created album
[group addAsset: asset];

//call the completion block
completionBlock(nil);

} failureBlock: completionBlock];

} failureBlock: completionBlock];

//should be the last iteration anyway, but just in case
return;
}

} failureBlock: completionBlock];
}

如何添加分组：
[[DataCenter defaultAssetsLibrary] addAssetsGroupAlbumWithName:[alertView textFieldAtIndex:0].text
resultBlock:resulBlock
failureBlock:nil];

转载自：http://www.2cto.com/kf/201307/231293.html