OKProject/Tools/LD_Def.swift
@@ -52,3 +52,26 @@ class TapButton:UIButton{ } final class Box<T> { // 声明一个别名 typealias Listener = (T) -> Void var listener: Listener? var value: T? { didSet { guard let v = value else { return } listener?(v) } } init(_ value: T? = nil){ self.value = value } func bind(listener: Listener?) { self.listener = listener guard let v = value else { return } listener?(v) } }