Question

我正在制作一个绘图应用程序，用户将图形保存为在照片中以编程方式创建的自定义相册中的图像。我想删除这些保存的图像，请告诉我如何从自定义相册中删除图像。

感谢。

Answer 1

它会起作用，

导入断言库#import <AssetsLibrary/AssetsLibrary.h>

首先，您应检索并存储任何数据库的图像路径

您可以使用以下代码检索存储的图像路径

ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];

[library writeImageToSavedPhotosAlbum:[[UIImage imageNamed:@"Dhoni.jpg"] CGImage] orientation:(ALAssetOrientation)[[UIImage imageNamed:@"Dhoni.jpg"] imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){
    if (error) {
        NSLog(@"error");
    } else {
        NSLog(@"url %@", assetURL);
    }  
}];

之后，通过使用路径，您可以删除图像

NSURL *deleteurl = [NSURL URLWithString: assetURL];
NSArray *arrDelete = [[NSArray alloc] initWithObjects:deleteurl , nil];
PHFetchResult *asset = [PHAsset fetchAssetsWithALAssetURLs:arrDelete  options:nil];

[asset enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    NSLog(@"%@",[obj class]);
    [[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
        BOOL req = [obj canPerformEditOperation:PHAssetEditOperationDelete];
        if (req) {
            NSLog(@"true");
            [PHAssetChangeRequest deleteAssets:@[obj]];
        }
    } completionHandler:^(BOOL success, NSError *error) {
        NSLog(@"Finished Delete asset. %@", (success ? @"Success." : error));
        if (success) {
            NSLog(@"delete successfully");
        }else{
            NSLog(@"delete Cancel");

        }
    }];

}];

Answer 2

删除自定义相册

IOS 10及以上：

注意：用户将获得弹出确认。

__block PHFetchResult *photosAsset;
        __block PHAssetCollection *collection;
        __block PHObjectPlaceholder *placeholder;

// Find the album
PHFetchOptions *fetchOptions = [[PHFetchOptions alloc] init];
NSString * collectionTitle = //.. the custom album name
fetchOptions.predicate = [NSPredicate predicateWithFormat:@"title = %@", collectionTitle];
// this is how we get a match for album Title held by 'collectionTitle'



NSArray * collections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAny options:fetchOptions];


[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{


    [collections enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        NSLog(@"Item %li = %@", (unsigned long)idx, obj);
        [PHAssetCollectionChangeRequest deleteAssetCollections:@[obj]];
    }];




} completionHandler:^(BOOL success, NSError *error) {

    if (success)
    {                  
        NSLog(@"success");
        NSLog(@"placeholder holds %@", placeholder.debugDescription );

    }
    else
    {
        NSLog(@"%@", error);
    }

}];

如何以编程方式从iOS中删除自定义相册中的图像？

2 个答案: