addSubview 不起作用

Question

I'm beginner in Objective-C. When I use addSubview in method setupView to see image, this doesn't work.

h.


    @interface CollectionViewController : UICollectionViewController 

    @end

    @interface MyCell : UICollectionViewCell 

    @end

and

m.


    @interface MyCell ()

    @end

    @implementation MyCell

    - (instancetype)initWithFrame:(CGRect)frame {
            self = [super initWithFrame:frame];
        if (self) [self setupView];
            return self;

        }

    - (id)initWithCoder:(NSCoder *)aDecoder
    {
        self = [super initWithCoder:aDecoder];
        if (self) [self setupView];
        return self;
    }

    -(UIImageView *)myImageView {

        UIImageView *imageView = [UIImageView new];
        imageView.image = [UIImage imageNamed:@"photo.jpg"];
        imageView.contentMode = UIViewContentModeScaleAspectFill;
        imageView.layer.masksToBounds = true;
        return imageView;

    }

    -(void)setupView {

        self.backgroundColor = [UIColor whiteColor];

        [self addSubview:self.myImageView];

    }

    @end

Answer 1

There are a lot of potential issues, but most likely the frame of the imageView isn't correct. Try creating it with

UIImage *image = [UIImage imageNamed:@"photo.jpg"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];