取消归档带有子视图的 UIImageView

Question

我有点疯狂地尝试归档和取消归档 UIImageView，它有许多子视图，这些子视图是从 UIImageView 派生的自定义视图。这是我所做的：

向项目添加一个类别，以允许 UIImage 不符合 NSCoding 的事实：

#import "UIImage-NSCoding.h"
#define kEncodingKey @"UIImage"

@implementation UIImage(NSCoding)

- (id)initWithCoder:(NSCoder *)decoder
{
    if ((self = [super init]))
    {
        NSData *data = [decoder decodeObjectForKey:kEncodingKey];
        self = [self initWithData:data];
    }        
    return self;
}

- (void)encodeWithCoder:(NSCoder *)encoder
{
    NSData *data = UIImagePNGRepresentation(self);
    [encoder encodeObject:data forKey:kEncodingKey];
}

@end

我正在存档的 UIImageView 是我的主视图控制器的一个属性，称为“背景”。我这样保存它：

NSData *dataToSave = [NSKeyedArchiver archivedDataWithRootObject:self.background];
[dataToSave dataWithContentsOfFile:imagePath options:NSDataWritingAtomic error:nil];

然后我像这样取消存档：

NSData *savedData = [NSData dataWithContentsOfFile:imagePath];    
UIImageView *restoredImageView = [NSKeyedUnarchiver unarchiveObjectWithData:savedData];
self.background.image = restoredImageView.image; // this works - archived image is displayed

现在我想让我的子视图（或至少其中之一！） 与未存档的根对象一起显示：

NSLog(@"Subviews: %d", [restoredImageView.subviews count]); // this tells me my subviews have been archived along with the root object
NSLog(@"Subview 0: %@", [restoredImageView.subviews objectAtIndex:0]); // and they exist as expected

NSLog(@"Subviews: %d", [self.background.subviews count]); // at this point no subviews are present
[self.background addSubview:[restoredImageView.subviews objectAtIndex:0]]; // subview is not visible on screen
NSLog(@"Subviews: %d", [self.background.subviews count]); // count is one, but where is it?

ORUImageView *oru = [[ORUImageView alloc] init]; // I try creating the subview myself
oru = [self.background.subviews objectAtIndex:0]; 
[self.background addSubview:oru]; // it still doesn't show on screen
[self.background bringSubviewToFront:oru]; // makes no difference

NSLog(@"String: %@", oru.testString); // this correctly logs the test string I added to my custom class

这是我添加到我的 ORUImageView 子类中的内容：

- (void)encodeWithCoder:(NSCoder *)aCoder
{
    [super encodeWithCoder:aCoder];    
    [aCoder encodeObject:self.testString forKey:@"theString"];
    [aCoder encodeObject:self.image forKey:@"theImage"]; // not sure if this is needed
}


- (id)initWithCoder:(NSCoder *)aDecoder
{
    self = [super initWithCoder:aDecoder];
    [self setTestString:[aDecoder decodeObjectForKey:@"theString"]];
    [self setImage:[aDecoder decodeObjectForKey:@"theImage"]]; // not sure if this is needed
    return self;
}

我已经尝试过使用和不使用图像属性的编码。

我怀疑问题与此属性有关，因为我显然已将子视图添加到未归档视图中 - 它只是不可见！我觉得图像属性没有设置，但我找不到自己设置它的方法，也找不到任何告诉我正确方法的信息。

Answer 1

唔。我刚刚尝试过这个：

- (IBAction)doButton1:(id)sender {
    theData = [NSKeyedArchiver archivedDataWithRootObject:iv];
    [iv removeFromSuperview];
    iv = nil;
}

- (IBAction)doButton2:(id)sender {
    iv = [NSKeyedUnarchiver unarchiveObjectWithData:theData];
    [self.view addSubview:iv];
}

它可以工作 - 使用普通的 UIImageView。所以现在我想我不明白你在说什么；看来 UIImageView 已与其图像一起存档。所以你一定是在尝试解决其他问题。但我不明白问题是什么。