Question

我创建了一个customView，在customView中，有一个imageView。当我将控件传递给customView并打印出我的imageView时，它返回null。不知道为什么。

·H

#import <UIKit/UIKit.h>

@interface GalleryImage : UIView
{
    IBOutlet UIImageView *galleryImageView;
}
- (id)initWithImage:(UIImage*) image;
@property(strong,nonatomic) IBOutlet UIImage *galleryImage;
@end

的.m

#import "GalleryImage.h"

@implementation GalleryImage

@synthesize galleryImage;

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Initialization code
    }
    return self;
}
- (id)initWithImage:(UIImage*) image
{
    self = [super init];
    if (self) {
        galleryImage = image;
        [galleryImageView setImage:galleryImage];
    }
    return self;
}

以这种方式传递控件：

UIImage *infoImage = [UIImage imageNamed:imageName];

GalleryImage *galleryItem = [[GalleryImage alloc] initWithImage:infoImage];

但我的galleryImageView返回null。知道为什么吗？

Answer 1

galleryImageView是一个IBOutlet，只有在从nib加载后才会获取内存。在它之前执行init方法.Hence imageview没有有效的内存，它返回null

在

中进行

awakeFromNib
Prepares the receiver for service after it has been loaded from an Interface Builder archive, or nib file.

所以使用这个

- (void)awakeFromNib {
        [galleryImageView setImage:galleryImage];
}

UIImageView在customView中返回nil

1 个答案: