我是創建一個scrollview，然後在裡面添加imageview,imageView的創建主要代碼如下：

@interface ImagePageView : UIView

@property (nonatomic,retain)UIImageView *imageViewOne;

@property (nonatomic,retain)UIImageView *imageViewTwo；

- (void)imageViewV:(int)pageNum;

- (void)imageViewH:(int)pageNum;

 

 

@implementation ImagePageView

 

@synthesize imageViewOne = _imageViewOne;

@synthesize imageViewTwo = _imageViewTwo;

- (UIImageView *)imageViewOne

{

    if (!_imageViewOne) {

        _imageViewOne = [[UIImageView alloc] init];

        [self addSubview:_imageViewOne];

    }

    return _imageViewOne;

}

 

- (UIImageView *)imageViewTwo

{

    if (!_imageViewTwo) {

        _imageViewTwo = [[UIImageView alloc] init];

        [self addSubview:_imageViewTwo];

    }

    return _imageViewTwo;

}

 

- (void)imageViewV:(int)pageNum

{

    _imageViewOne.image = [[[UIImage alloc] initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[array objectAtIndex:pageNum] ofType:nil]] autorelease];

    _imageViewOne.frame = self.bounds;

  

}

   就是這樣的代碼，結果不能顯示。不久找到了問題，紅色部分應該改為：

self.imageViewOne.image = [[[UIImage alloc] initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[array objectAtIndex:pageNum] ofType:nil]] autorelease];

 self.imageViewOne.frame = self.bounds;

 原因是這樣的，紅色代碼並不會調用初始化的代碼（- (UIImageView *)imageViewTwo/- (UIImageView *)imageViewOne），所以imageViewOne為nil，導致無法顯示圖片。

而self.imageViewOne則會調用get方法。