In Kotlin there appears to be two method of declaring a variable inside an object that can be null and instantiated after the object is created.
var myObject : Any? = null
or
var lateinit myObject : Any
I am confused about why the lateinit keyword is needed if we can just make the var nullable and assign it later. What are the pros and cons of each method and in what situation should each one be used?
Here is how I see the difference according to my current knowledge in Kotlin.
第一个:
var myObject1 : Any? = null
这里的myObject1是一个可以为空的属性.这意味着您可以将null分配给它.
Second one:
lateinit var myObject2 : Any
这里myObject2是一个非空属性.这意味着你不能给它分配null.通常，如果属性为非null，则必须在声明时对其进行初始化.但是添加关键字lateinit可以推迟初始化.如果在初始化lateinit属性之前try 访问它，则会出现异常.
In short the main difference is that myObject1 is a nullable and myObject2 is a non-null. The keyword lateinit provide you a convenience mechanism to allow a non-null property to be initialize at a later time rather than initializing it at the declaration.
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