iPhone可笑的内存泄漏

Question

我已经被我的 iPhone 应用程序的内存泄漏问题困扰了很长时间了。我觉得我的数据读错了。似乎每当我分配内存时，都会有太多的开销导致泄漏，当我释放数据时，我的内存使用量要么几乎没有下降，要么根本没有下降。其中浪费了 2 天的时间是我的翻转视图控制器上的 UIWebview 加载了一个 url，并且我的应用程序的内存使用量从 3 mb 跳到了 7。我在 dealloc 方法中释放了 webview，但巨大的内存块仍然存在。有没有人有什么建议。

- (void)viewDidLoad {
self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];

nav_bar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0,0,self.view.frame.size.width+20,45)];
[self.view addSubview:nav_bar];
[UINavigationBar release];

rightButton = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(done)];
item = [[UINavigationItem alloc] initWithTitle:@"Flipside View"];
item.rightBarButtonItem = rightButton;
item.hidesBackButton = YES;
[nav_bar pushNavigationItem:item animated:NO];
[rightButton release];
[item release];

NSAutoreleasePool *initPool = [[NSAutoreleasePool alloc] init];

web_view = [[UIWebView alloc]initWithFrame:CGRectMake(0,45,self.view.frame.size.width,self.view.frame.size.height - 45)];

web_view.autoresizesSubviews = YES;
web_view.autoresizingMask=(UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth);

NSString *urlAddress = @"http://www.tutorialpark.com/wpcontent/uploads/3/HeartBlending.jpg";
NSURL *url = [NSURL URLWithString:urlAddress];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];

[web_view loadRequest:requestObj];
[self.view addSubview:web_view];
[web_view release];
[initPool release];

[super viewDidLoad];
}

- (void)dealloc {
   [nav_bar removeFromSuperview];
   [web_view removeFromSuperview];
   [rightButton release];
   [super dealloc];
}

我对缩进表示歉意，我现在很生气，不想处理它。

Answer 1

您似乎对引用计数的工作原理感到困惑。

请参阅下面的评论：

- (void)viewDidLoad {
  self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];

  UINavigationBar* nav_bar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0,0,self.view.frame.size.width+20,45)];
  // nav_bar retaincount 1
  [self.view addSubview:nav_bar];
  // nav_bar retaincount 2
  [nav_bar release];
  // nav_bar retaincount 1 - now controlled by self.view

  UIBarButtonItem* rightButton = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(done)];
  // rightButton retaincount 1

  UINavigationItem* item = [[UINavigationItem alloc] initWithTitle:@"Flipside View"];
  // item retaincount 1

  item.rightBarButtonItem = rightButton;
  // rightButton retaincount 2

  [rightButton release];
  // rightButton retaincount 1 - now controlled by item

  item.hidesBackButton = YES;
  [nav_bar pushNavigationItem:item animated:NO];
  // item retaincount 2

  [item release];
  // item retaincount 1 - now controlled by nav_bar

  UIWebView* web_view = [[UIWebView alloc]initWithFrame:CGRectMake(0,45,self.view.frame.size.width,self.view.frame.size.height - 45)];
  // web_view retaincount 1

  web_view.autoresizesSubviews = YES;
  web_view.autoresizingMask=(UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth);

  NSString *urlAddress = @"http://www.tutorialpark.com/wpcontent/uploads/3/HeartBlending.jpg";

  NSURL *url = [NSURL URLWithString:urlAddress];
  // url is autoreleased, you can ignore..

  NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
  // requestObj is autoreleased, you can ignore..

  [web_view loadRequest:requestObj];

  [self.view addSubview:web_view];
  // web_view retaincount 2

  [web_view release];
  // web_view retaincount 1 - now controlled by self.view

  [super viewDidLoad];
}

- (void)dealloc {
   // don't need to do anything because all the memory is controlled by self.view, will be released when the internal variable self.view is released.
   [super dealloc];
}

Answer 2

[UINavigationBar发布]； - 这是在做什么？它是否意味着 [nav_bar release] ？ - 如果是这样，应该稍后在您再次访问 nav_bar 的代码稍下方完成。但那好像是一个成员变量？所以应该在dealloc中释放。

rightButton 被释放两次 - 一次在 viewDidLoad 中，一次在 dealloc 中。

您能解释一下自动释放池的用途吗？