Question

如何在核心数据中保存由UIImagePickerController挑选的照片。在我的数据模型中，我将其设置为类型Binary Data并允许它存储在外部到目前为止，这是我的代码。

- (IBAction)addPhoto:(id)sender {
_picker = [[UIImagePickerController alloc]init];
_picker.delegate = self;
_picker.allowsEditing = NO;
_picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
[self presentViewController:_picker animated:YES completion:nil];


}
-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo {
AppDelegate *delegate = [UIApplication sharedApplication].delegate;
NSManagedObjectContext *context = [delegate managedObjectContext];
NSManagedObject *object = [NSEntityDescription insertNewObjectForEntityForName:@"Device" inManagedObjectContext:context];


[self dismissViewControllerAnimated:YES completion:nil];
[self.imageView reloadInputViews];



}

Answer 1

使用您的代码：

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo {
AppDelegate *delegate = [UIApplication sharedApplication].delegate;
NSManagedObjectContext *context = [delegate managedObjectContext];
NSManagedObject *object = [NSEntityDescription insertNewObjectForEntityForName:@"Device" inManagedObjectContext:context];

    // One option:
    NSData *imageData =  UIImageJPEGRepresentation(image, 0.7);
    // Second option.
   // NSData *imagenData2 = UIImagePNGRepresentation(image);

object.theNameOfYourBinaryDataAttribute = imageData;

[context save:nil]; // Or handling error.

[self dismissViewControllerAnimated:YES completion:nil];
[self.imageView reloadInputViews];



}

Answer 2

由于UIImage符合NSCoding，您需要做的就是将属性类型从“二进制”更改为“可转换”。然后，您可以直接为该属性分配UIImage，Core Data将自动在其上调用NSCoding方法以转换为二进制数据和从二进制数据转换。

在您的代码中，您只需添加以下内容：

[object setValue:image forKey:@"name of your image attribute here"];

在核心数据上保存UIImage

2 个答案: