iOS-保存图片到(自定义)相册步骤

保存到相册步骤：

1.保存图片到【相机胶卷】

2.拥有一个【自定义相册】

3.将刚才保存到【相机胶卷中的图片】引用到【自定义相册】

①保存图片到【相机胶卷】

/*
 一、保存图片到【自定义相册】
 1.保存图片到【相机胶卷】
 1> C语言函数UIImageWriteToSavedPhotosAlbum
 2> AssetsLibrary框架
 3> Photos框架
 
 2.拥有一个【自定义相册】
 1> AssetsLibrary框架
 2> Photos框架
 
 3.添加刚才保存的图片到【自定义相册】
 1> AssetsLibrary框架
 2> Photos框架
 */
- (IBAction)save:(UIButton *)sender {
    /*
     保存到相册步骤：
     1.保存图片到【相机胶卷】
     2.拥有一个【自定义相册】
     3.将刚才保存到【相机胶卷中的图片】引用到【自定义相册】
     */
    UIImageWriteToSavedPhotosAlbum(self.imageView.image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
}
- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
    if (error) {
        [SVProgressHUD showErrorWithStatus:@"保存失败！"];
    } else {
        [SVProgressHUD showSuccessWithStatus:@"保存成功！"];
    }
}

/*
//补充
 错误信息：-[NSInvocation setArgument:atIndex:]: index (2) out of bounds [-1, 1]
 错误解释：参数越界错误，方法的参数个数和实际传递的参数个数不一致
 */

Photos框架详解和保存图片

1.Photos框架详解

/*
二、Photos框架须知
 1.PHAsset : 一个PHAsset对象就代表相册中的一张图片或者一个视频
 1> 查 : [PHAsset fetchAssets...]
 2> 增删改 : PHAssetChangeRequest(包括图片\视频相关的所有改动操作)
 
 2.PHAssetCollection : 一个PHAssetCollection对象就代表一个相册
 1> 查 : [PHAssetCollection fetchAssetCollections...]
 2> 增删改 : PHAssetCollectionChangeRequest(包括相册相关的所有改动操作)
 
 3.对相片\相册的任何【增删改】操作，都必须放到以下方法的block中执行
 -[PHPhotoLibrary performChanges:completionHandler:]
 -[PHPhotoLibrary performChangesAndWait:error:]
 */

/*
 Foundation和Core Foundation的数据类型可以互相转换，比如NSString *和CFStringRef
 NSString *string = (__bridge NSString *)kCFBundleNameKey;
 CFStringRef string = (__bridge CFStringRef)@"test";
 
 获得相机胶卷相册
 [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil]
 */

/*
 错误信息：This method can only be called from inside of -[PHPhotoLibrary performChanges:completionHandler:] or -[PHPhotoLibrary performChangesAndWait:error:]
 
 // 异步执行修改操作
 [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
 [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image];
 } completionHandler:^(BOOL success, NSError * _Nullable error) {
 if (error) {
 [SVProgressHUD showErrorWithStatus:@"保存失败！"];
 } else {
 [SVProgressHUD showSuccessWithStatus:@"保存成功！"];
 }
 }];
 
 // 同步执行修改操作
 NSError *error = nil;
 [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
 [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image];
 } error:&error];
 if (error) {
 [SVProgressHUD showErrorWithStatus:@"保存失败！"];
 } else {
 [SVProgressHUD showSuccessWithStatus:@"保存成功！"];
 }
*/

2.Photos框架保存图片到相机胶卷

- (IBAction)save:(UIButton *)sender {
    /*
     保存到相册步骤：
     1.保存图片到【相机胶卷】
     2.拥有一个【自定义相册】
     3.将刚才保存到【相机胶卷中的图片】引用到【自定义相册】
     */
    NSError *error = nil;

    // 保存图片到【相机胶卷】
    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
        [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image];
    } error:&error];

    if (error) {
        [SVProgressHUD showErrorWithStatus:@"保存失败！"];
    } else {
        [SVProgressHUD showSuccessWithStatus:@"保存成功！"];
    }
}

 

②拥有一个【自定义相册】

 Foundation和Core Foundation的数据类型可以互相转换，比如NSString *和CFStringRef

 NSString *string = (__bridge NSString *)kCFBundleNameKey;

 CFStringRef string = (__bridge CFStringRef)@"test";

1.创建一个【自定义相册】

/** 当前App对应的自定义相册 */
- (PHAssetCollection *)createdCollection;

- (IBAction)save:(UIButton *)sender {
    /*
     保存到相册步骤：
     1.保存图片到【相机胶卷】
     2.拥有一个【自定义相册】
     3.将刚才保存到【相机胶卷中的图片】引用到【自定义相册】
     */
    [self createdCollection];
}

#pragma mark - 获得当前App对应的自定义相册
- (PHAssetCollection *)createdCollection
{
    // 获得软件名字
    NSString *title = [NSBundle mainBundle].infoDictionary[(__bridge NSString *)kCFBundleNameKey];
    
    // 抓取所有的自定义相册
    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创建过 **/
    // 创建一个【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) {
        [SVProgressHUD showErrorWithStatus:@"创建相册失败！"];
        return nil;
    }
    
    // 根据唯一标识获得刚才创建的相册
    return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[createdCollectionID] options:nil].firstObject;
}
/*
 Foundation和Core Foundation的数据类型可以互相转换，比如NSString *和CFStringRef
 NSString *string = (__bridge NSString *)kCFBundleNameKey;
 CFStringRef string = (__bridge CFStringRef)@"test";
 
 获得相机胶卷相册
 [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary options:nil]
 */

2.获取相册

#pragma mark - 获得当前App对应的自定义相册
// 根据唯一标识获得刚才创建的相册
 return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[createdCollectionID] options:nil].firstObject;

3.保存图片到自定义相册

/** 当前App对应的自定义相册 */
- (PHAssetCollection *)createdCollection;
/** 返回刚才保存到【相机胶卷】的图片 */
- (PHFetchResult<PHAsset *> *)createdAssets;

- (IBAction)save:(UIButton *)sender {
    PHAuthorizationStatus oldStatus = [PHPhotoLibrary authorizationStatus];
    
    // 请求\检查访问权限 :
    // 如果用户还没有做出选择，会自动弹框，用户对弹框做出选择后，才会调用block
    // 如果之前已经做过选择，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) {
                    HKLog(@"提醒用户打开开关")
                }
            } else if (status == PHAuthorizationStatusAuthorized) { // 用户允许当前App访问相册
                [self saveImageIntoAlbum];
            } else if (status == PHAuthorizationStatusRestricted) { // 无法访问相册
                [SVProgressHUD showErrorWithStatus:@"因系统原因，无法访问相册！"];
            }
        });
    }];
}

/**
 *  保存图片到相册
 */
- (void)saveImageIntoAlbum
{
    // 获得相片
    PHFetchResult<PHAsset *> *createdAssets = self.createdAssets;
    if (createdAssets == nil) {
        [SVProgressHUD showErrorWithStatus:@"保存图片失败！"];
        return;
    }
    
    // 获得相册
    PHAssetCollection *createdCollection = self.createdCollection;
    if (createdCollection == nil) {
        [SVProgressHUD showErrorWithStatus:@"创建或者获取相册失败！"];
        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 - 获得当前App对应的自定义相册
- (PHAssetCollection *)createdCollection
{
    // 获得软件名字
    NSString *title = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleDisplayName"];
    
    // 抓取所有的自定义相册
    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创建过 **/
    // 创建一个【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;
    
    // 根据唯一标识获得刚才创建的相册
    return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[createdCollectionID] options:nil].firstObject;
}

- (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];
}

//补充：不带权限判断
//- (IBAction)save {
//    NSError *error = nil;
//
//    // 保存图片到【相机胶卷】
//    __block PHObjectPlaceholder *placeholder = nil;
//    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
//        placeholder = [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image].placeholderForCreatedAsset;
//    } error:&error];
//    if (error) {
//        [SVProgressHUD showErrorWithStatus:@"保存图片失败！"];
//        return;
//    }
//
//    // 获得相册
//    PHAssetCollection *createdCollection = self.createdCollection;
//    if (createdCollection == nil) {
//        [SVProgressHUD showErrorWithStatus:@"创建相册失败！"];
//        return;
//    }
//
//    // 添加刚才保存的图片到【自定义相册】
//    [[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
//        PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:createdCollection];
//        [request insertAssets:@[placeholder] 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！"];
//    }
//}