Android Interface Kotlin Example

Here is the tutorial for Java

Interface Kotlin  Example

1/ Create A New Project And Create an array  and add some value

package com.example.interfacetest

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log

class MainActivity : AppCompatActivity(){


    override fun onCreate(savedInstanceState: Bundle?) {

        val bookList =ArrayList<String>()
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        bookList.add("Java Book")
        bookList.add("Kotlin Book")
        bookList.add("Flutter Book")

    }

}

2/ Crate an Interface name is BookData

package com.example.interfacetest

interface BookData {

    fun myBook(bookName:String)
}

3/ Create a class BookClass

package com.example.interfacetest

class BookClass() {


}

4/ Add parameter  and create function

package com.example.interfacetest

class BookClass(val bookList:ArrayList<String>, val bookData: BookData) { // Add Parameter
    
    fun getMyBook( index:Int){ //Create Function
       var myBookName= bookList.get(index)
        bookData.myBook(myBookName) // Sent Data
    }
}

5/ In MainActivity Implement BookData and Override myBook

package com.example.interfacetest

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log

class MainActivity : AppCompatActivity() , BookData{// Implement BookData
    
    override fun onCreate(savedInstanceState: Bundle?) {

        val bookList =ArrayList<String>()
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        bookList.add("Java Book")
        bookList.add("Kotlin Book")
        bookList.add("Flutter Book")

   
    }

    override fun myBook(bookName: String) {// Add Override Function 
     

    }
}

package com.example.interfacetest

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log

class MainActivity : AppCompatActivity() , BookData{
    
    override fun onCreate(savedInstanceState: Bundle?) {

        val bookList =ArrayList<String>()
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        bookList.add("Java Book")
        bookList.add("Kotlin Book")
        bookList.add("Flutter Book")

       var bookClass= BookClass(bookList,this)// Send data in to class
        bookClass.getMyBook(1) // Call to function
    }

    override fun myBook(bookName: String) {
       Log.d("Output : ",bookName) // Output

    }
}