嵌套块和对self的引用 [英] Nested blocks and references to self

问题描述

我有一个块，其中我使用 self 所以我声明了对self的弱引用：

I have a block wherein I use self so I declare a weak reference to self:

__weak MyClass *weakSelf = self;

现在我的问题：

1. 我在定义 weakSelf 时遇到错误，我不明白这应该是什么意思。：

1. I get an error where I define weakSelf and I don't understand what this should mean.:

无法在自动变量上指定弱属性

weak attribute can not be specified on an automatic variable

在我的块中，我传递 weakSelf 到另一个区块，我不确定我现在是否必须再次做同样的事情：

Inside my block I pass weakSelf to another block and I am not sure if I now have to do the same thing again like so:

__weak MyClass *weakWeakSelf = weakSelf;

然后将 weakWeakSelf 传递给该区块？

And then pass weakWeakSelf to that block?

推荐答案

这很有可能发生在你瞄准iOS 4时你应该把它改成

This is most likely occurring as you are targeting down to iOS 4. You should change it to be

__unsafe_unretained MyClass *weakWeakSelf = weakSelf;

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