如何在同伴对象外部检查它内部的lateinit var是否初始化[重复]

Question

class MyClass
{
    companion object
    {
        lateinit var user:User
    }

    init
    {
        //initialize if not initialized
        //user.isInitialized
        user = User
    }
}

Answer 1

只需使用一个可空变量。

1. 不安全方法（不安全的方式与lateinit相同）:

class MyClass {
    companion object {
        val user get() = user_ ?: throw UninitializedPropertyAccessException("property has not been initialized")
        private var user_: User? = null
    }

    init {
        if (user_ == null) user_ = User()
    }
}

现在您可以访问该属性：

MyClass.user.example()

class MyClass {
    companion object {
        var user: User? = null; private set
    }

    init {
        if (user == null) user = User()
    }
}

MyClass.user?.example()