在使用swift时碰到block 引用循环。特此记一笔。

取个网名用了半个小时

于 2014-09-28 17:23:09 发布

阅读量911

点赞数

本文介绍如何在Swift中使用弱引用来避免闭包引起的内存循环问题。通过使用弱引用，可以有效防止对象间相互持有强引用而导致的内存泄漏。Swift还提供了更简洁的捕获列表语法来进一步简化弱引用的管理。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

In objective c in order to avoid retain cycles when using blocks a weak reference is passed to the block

__weak SomeViewController *weakSelf =
self;
 
[self
performTask:^{
   [weakSelf callSomeMethod];
}];

In swift we can do something similar

weak var weakReference =
self
 
performTask() {
    weakReference.callSomeMethod()
}

Swift has a feature called Captureless that further simplifies managing weak references. Using captureless the code would look like

performTask() { [weak
self] in
    self.callSomeMethod()
}

Captureless also allows multiple weak references to be passed to the closure

performTask() { [weak
self, anotherVariableWithWeakReference] in
    self.callSomeMethod()
}

附上链接：http://aryaxt.wordpress.com