iPhone：如何使用NSUserDefaults存儲UIImage？

Question

我無法使用nsuserdefaults保存圖像並使應用崩潰，並且我還使用了自定義類UserInfo

-(void)encodeWithCoder:(NSCoder *)encoder
{
   NSData *imageData = UIImagePNGRepresentation(categoryImage);
   [encoder encodeObject:categoryName forKey:@"name"];
   [encoder encodeObject:imageData forKey:@"image"];
}

-（id）initWithCoder：（NSCoder *）解碼器和userInfo.categoryImage是UIImage變量。

原因：'-[UIImage encodeWithCoder：]：無法識別的選擇器已發送到實例0x7676a70'

userInfo = [[UserInfo alloc] init];

userInfo.categoryName = categoryName.text;
NSLog(@"Category Name:--->%@",userInfo.categoryName);

userInfo.categoryImage = image;

appDelegate.categoryData = [[NSMutableDictionary dictionaryWithObjectsAndKeys:
                                 userInfo.categoryName, @"name",userInfo.categoryImage,@"image", nil] mutableCopy];


[appDelegate.categories addObject:appDelegate.categoryData];
NSLog(@"Category Data:--->%@",appDelegate.categories);

[appDelegate.categories addObject:userInfo.categoryName];
[appDelegate.categories addObject:userInfo.categoryImage];

[self saveCustomObject:userInfo.categoryName];

[self saveCustomObject:userInfo.categoryImage];


-(void)saveCustomObject:(UserInfo *)obj
{
    appDelegate.userDefaults = [NSUserDefaults standardUserDefaults];
    NSData *myEncodedObject = [NSKeyedArchiver archivedDataWithRootObject:obj];


    [appDelegate.userDefaults setObject:myEncodedObject forKey:@"myEncodedObjectKey"];
}

因此，請幫助我如何使用nsusedefaults存儲和檢索uiimage？

Answer 1

如果您是我，我將UIImage保存到文件中（使用[myImage hash];生成文件名），然后使用NSUserDefault ;-)將文件名另存為NSString。

Answer 2

UIImage沒有實現NSCoding協議，這就是為什么出現錯誤的原因。

商店：

NSData* imageData = UIImagePNGRepresentation(image);
NSData* myEncodedImageData = [NSKeyedArchiver archivedDataWithRootObject:imageData];
[appDelegate.userDefaults setObject:myEncodedImageData forKey:@"myEncodedImageDataKey"];
}

恢復：

NSData* myEncodedImageData = [appDelegate.userDefaults objectForKey:@"myEncodedImageDataKey"];
UIImage* image = [UIImage imageWithData:myEncodedImageData];

Answer 3

圖片保存在NSUserDefaults上：

      [[NSUserDefaults standardUserDefaults] setObject:UIImagePNGRepresentation(image) forKey:@"image"];   

在NSUserDefaults上檢索圖像：

NSData* imageData = [[NSUserDefaults standardUserDefaults] objectForKey:@"image"];
    UIImage* image = [UIImage imageWithData:imageData];