import Foundation public class SwiftSingleton{
var name = "000"
public static let instance = SwiftSingleton() //这个位置使用 static,static修饰的变量会懒加载
private init(){
print( "create SwiftSingleton..." );
}
} |
然后看测试:
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override func viewDidLoad() { super.viewDidLoad()
print( "viewDidload" );
let s1 = SwiftSingleton.instance
let s2 = SwiftSingleton.instance
s1.name = "s1"
s2.name = "s2"
print( "s1.name:\(s1.name) s2.name:\(s2.name)" )
}
|
打印结果:
viewDidload
create SwiftSingleton...
s1.name:s2 s2.name:s2
从打印结果来看,这个单例确实是懒加载的,而且,确实是单例。
OK了