Kotlin : Extension Functions (Post 9)

Hi ,

Here is another post related to Kotlin basics for beginners , in this post I will discuss the Kotlin Extension Function ,let's get started :

So sometimes , we feel that one important functionality is missing from a class and
 we want to add that function :
we need to extend that class, and then add that function and then use that extended class.

But in Kotlin , helps definitely on this by providing Extension Functions

Extension Functions are:

• - can "add" new functions to a class without declaring it 
• - the new functions added behaves like "static" in java

So let's take a look in code first , then we will discuss briefly on this :

override fun onCreate(savedInstanceState: Bundle?) {
  super.onCreate(savedInstanceState)
  setContentView(R.layout.activity_main)
  var  i : Int  = 45
  var j : Int = 91
  println("In I: $i & in J: $j , greater number is : "+ i.findTheGreaterNum(j))
}

/**
 * Extension Function
*/
fun Int.findTheGreaterNum(j :Int) : Int {
        if(this > j)
            return this
        else
            return j
 }

Here we can see the there was no function "findTheGreaterNum()" in Int class , but we can make this like extension function of Int class .

Here this will annotate for i , bcoz  the function is class for i object.

Same like this we can make the extension functions for our own classes as well.

That's all for extension functions , will post more for kotlin , till then Happy Coding :)