Swift 闭包中循环引用解决方式
示例说明:开启一个定时器,然后每隔一秒钟加1秒,直到60秒
变量声明
- //声明一个定时器变量
- var timer: Timer?
- var currentSeconds: Int = 0
weak 方式
- func testTimer(){
-
- weak var weakSelf : CurrentController? = self
- timer = Timer.scheduledTimer(withTimeInterval: 1.0,repeats: true,block: { _ in
-
- weakSelf?.currentSeconds += 1
-
- if weakSelf?.currentSeconds == 60{
-
- weakSelf?.timer?.invalidate()
- weakSelf?.timer = nil
- }
- })
- }
[weak self] 方式
- func testTimer(){
- timer = Timer.scheduledTimer(withTimeInterval: 1.0,repeats: true,block: {[weak self] (_) in
-
- self?.currentSeconds += 1
-
- if self?.currentSeconds == 60{
-
- self?.timer?.invalidate()
- self?.timer = nil
- }
- })
- }
[unowned self] 方式
- func testTimer(){
-
- timer = Timer.scheduledTimer(withTimeInterval: 1.0,block: {[unowned self] (_) in
-
- self.currentSeconds += 1
-
- if self.currentSeconds == 60{
- self.timer?.invalidate()
- self.timer = nil
- }
- })
- }