I am defining like a instance variable in kotlin
and want to initialize it onCreate
method of an activity
.
var count:
There are several ways to resolve this issue.
You can Initialise it with default value (e.i 0
or -1
or whatever) and then initialise it whenever your logic says.
Or tell compiler that count will be initialised later in this code by using Delegates.notNull
check notNull.
var count: Int by Delegates.notNull<Int>()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// You can not call `Int.inc()` in onCreate()` function until `count` is initialised.
// count.inc()
// **initialise count**
}
And if you need count value on demand (if not necessary to initialise in onCreate
), you can use lazy
function. Use this only if you have an intensive (Some calculation/Inflating a layout etc) task that you want to do on demand
, Not to just assign a value.
var count:Int by lazy {
// initialise
}
Now you can decide what to use.
I hope it helps.
There's no reason to leave it uninitialized. Just initialize it to 0 or -1.
lateinit
is for non-null object references that can't easily be initialized in the class body definition.