iOS ARC不取消分配视图 [英] iOS ARC Not deallocating views

问题描述

我们正在创建一个带有主菜单的应用程序，您可以从中导航到带有后退按钮的第二个视图，还有大约6个其他按钮，将6个不同的子视图加载到内存(数组)中，具体取决于您选择的那个视图.

We are creating an application with a main menu from which you can navigate to a second view with a back button and about 6 other buttons wich loads 6 different subviews into memory (array) depending wich one you selected.

当用户选择后退"按钮时，我想从屏幕上用6个按钮分配的内存中删除所有内容.

When the user selects the 'back' button I want to erase anything from memory that was allocated in the screen with the 6 buttons.

此刻，应用程序仅建立了内存，似乎没有任何释放. 请在下面的URL中查看屏幕截图:

At the moment the application just builds up memory amd nothing seems to get deallocated. Please see the screenshot in the URL below:

http://oi41.tinypic.com/jfi8ma.jpg

 //Load all tab views into memory before loading them into an array
TimeViewController *timeView = [[TimeViewController alloc]init];
LocationViewController *locationView = [[LocationViewController alloc]init];
DropOffViewController *dropOffView = [[DropOffViewController alloc]init];
CompanyViewController *companyView = [[CompanyViewController alloc]init];
PaymentViewController *paymentView = [[PaymentViewController alloc]init];

//Set delegates of the tab views
timeView .delegate = self;
locationView.delegate = self;

//Load all tab views into array
[tabViews insertObject:timeView atIndex:0];
[tabViews insertObject:locationView atIndex:1];
[tabViews insertObject:dropOffView atIndex:2];
[tabViews insertObject:companyView atIndex:3];
[tabViews insertObject:paymentView atIndex:4];

for(int x = 0; x<5;x++)
{
    UIViewController *tempView = [[UIViewController alloc]init];
    tempView = [tabViews objectAtIndex:x];

    [self addChildViewController:tempView];
}

感谢您的帮助

推荐答案

您创建了一个保留周期.

You created a retain cycle.

您宣布您的代表具有强大的财产.这意味着当你这样做

You declared your delegates as strong properties. It means that when you do

timeView .delegate = self;

timeView保留self.

将timeView作为子视图控制器添加到self时，self保留timeView.

When you add timeView as child view controller to self, self retains timeView.

如果self强烈引用tabViews，则它是tabViews的所有者，这是添加到其中的对象的所有者，这将导致另一个保留周期:self拥有tabViews并拥有<拥有self的c0>.

If self holds strong reference to tabViews, then it's an owner of tabViews, which is an owner of objects added to it, which makes another retain cycle: self owns tabViews which owns timeView which owns self.

如果您不希望保留周期，则您的子对象一定不要对父母或父母中的任何父母持有强烈的引用.永远不要将委托声明为强属性.

If you don't want retain cycles, your child objects must never hold strong references to their parents or any of their parents' parents. Never declare delegates as strong properties.

至于您的必须__弱"错误，请参见此答案.

As for your "must be __weak" error, please see this answer.

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