對象泄漏：添加UIImageView並將其移除到UIScrollView

Question

我想動態添加圖像到ScrollView。在添加之前，我會檢查ScrollView中是否有子視圖，並在for循環中刪除它們。

當我釋放imageview時，我得到一個運行時錯誤，說明我試圖訪問一個釋放的實例。如果刪除了發佈聲明的應用程序將正常運行，但「建立與分析」顯示了泄漏，因爲日ImageView的不下降的引用計數..

if ([scrollView.subviews count]>0){ 
    for (int i=0; i<[scrollView.subviews count]; ++i) { 
     [[scrollView.subviews objectAtIndex:i] removeFromSuperview]; 
    } 
} 

//Making a scroller with results 
int scrollWidth = 0.0f; 
int scrollHeight = 0.0f; 
for (int i = 0; i<previewImages.count;++i) 
{ 
    UIImage *image=[previewImages objectAtIndex:i]; 
    scrollWidth = scrollWidth + image.size.width; // Width of all the images 
    if (image.size.height > scrollHeight)scrollHeight= image.size.height; // Maximum image height 
    [image release]; 
} 

float xC = 0.0f; 
for (int i=0; i<previewImages.count; ++i) { 

    UIImage *image=[previewImages objectAtIndex:i]; 
    UIImageView *imageview = [[UIImageView alloc] initWithFrame:CGRectMake(xC, 0.0f, image.size.width, image.size.height)]; 
    UILabel *subScript = [[UILabel alloc] initWithFrame:CGRectMake(xC, image.size.height-30.0f, image.size.width,30.0f)]; 

    subScript.textColor = [UIColor whiteColor]; 
    subScript.backgroundColor = [UIColor colorWithWhite:0.5f alpha:0.5f]; 
    subScript.text = [imagePaths objectAtIndex:i]; 

    imageview.image = image; 

    xC = xC + image.size.width; 
    [image release]; 
    [scrollView addSubview:imageview]; 
    [imageview release]; 
    [scrollView addSubview:subScript]; 
    [subScript release]; 
} 
[scrollView setContentSize:CGSizeMake(scrollWidth , scrollHeight)]; 

對內存泄漏或通用的最佳實踐添加任何建議並從數組中刪除視圖到scrollView非常感謝！

Answer 1

if ([scrollView.subviews count]>0){ 
    for (int i=0; i<[scrollView.subviews count]; ++i) { 
     [[scrollView.subviews objectAtIndex:i] removeFromSuperview]; 
    } 
} 

是錯誤的，因爲您要從子視圖數組中刪除子視圖。逆向迭代可以解決這個問題，但我建議將視圖保持在分隔數組中。