TTImageView問題

Question

我想在TTScrollView中顯示一些TTImageView。

- (UIView*)scrollView:(TTScrollView*)scrollView pageAtIndex:(NSInteger)pageIndex { 

TTView* pageView = nil; 
if (!pageView) { 
    pageView = [[[TTView alloc] init] autorelease]; 
    pageView.backgroundColor = [UIColor clearColor]; 
    pageView.userInteractionEnabled = NO; 
} 

NSString *imagePath = [self.screenShotImgPath objectAtIndex:pageIndex]; 
TTImageView *imageView = [[[TTImageView alloc] initWithFrame:CGRectZero] autorelease]; 
imageView.autoresizesToImage = YES; 
imageView.urlPath = imagePath; 
imageView.backgroundColor = [UIColor clearColor]; 
imageView.delegate = self; 


//here I need to rotate image 
if (imageView.width > imageView.height){ 
    CGAffineTransform tran = CGAffineTransformIdentity; 
    CGSize    bnds = imageView.size; 
    CGSize    bnds2 = imageView.size; 
    bnds = [self swapWidthAndHeight:bnds]; 
    tran = CGAffineTransformMakeTranslation(0.0,bnds2.width); 
    tran = CGAffineTransformRotate(tran, [self degreesToRadians:-90.0]); 
    imageView.transform = tran; 

} 

//here I need to scale image view frame to fit image actual scale 
CGFloat scale = imageView.width/imageView.height; 
CGFloat scaledWidth = (scrollView.height - 20.f) * scale; 
imageView.frame = CGRectMake((scrollView.width - scaledWidth)/2, 10.f, scaledWidth, scrollView.height - 20.f); 
[pageView addSubview:imageView]; 
return pageView; 
} 

但有一個問題：TTImageView異步下載圖像。所以這是退出可能，當代碼去

if (imageView.width > imageView.height){ 

此行圖像未加載。所以拋出異常。

由於圖像視圖在

- (UIView*)scrollView:(TTScrollView*)scrollView pageAtIndex:(NSInteger)pageIndex { 

添加，所以我不能移動下面的代碼旋轉出這個方法

if (imageView.width > imageView.height){ 
    CGAffineTransform tran = CGAffineTransformIdentity; 
    CGSize    bnds = imageView.size; 
    CGSize    bnds2 = imageView.size; 
    bnds = [self swapWidthAndHeight:bnds]; 
    tran = CGAffineTransformMakeTranslation(0.0,bnds2.width); 
    tran = CGAffineTransformRotate(tran, [self degreesToRadians:-90.0]); 
    imageView.transform = tran; 
    } 

我能做些什麼來solove這個問題的？

Answer 1

您可以在您的.h文件 添加<TTImageViewDelegate>，並在此.M功能：

#pragma mark TTImageViewDelegate 
-(void) imageView:(TTImageView *)imageView didLoadImage:(UIImage *)image{  
    if (image){ 
     //do your logic 
    } 
} 

當圖像完成加載，此功能將被觸發。