Vfrdtyky

I was trying to send the word ArrayList in other ArrayDapter class, but the error arises that it has too many arguments and super keyword in kotlin can only be used on the left side of "." operator.

    package com.example.android.miwok



import android.support.v7.app.AppCompatActivity

import android.os.Bundle

import android.util.Log

import android.widget.LinearLayout

import android.widget.TextView

import android.widget.ArrayAdapter

import android.widget.ListView





class NumbersActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {

    super.onCreate(savedInstanceState)

    setContentView(R.layout.activity_numbers)



    val words = ArrayList<Word>()

    words.add(Word("one","lutti"))

    words.add( Word("two", "otiiko"));

    words.add( Word("three", "tolookosu"));

    words.add( Word("four", "oyyisa"));

    words.add( Word("five", "massokka"));

    words.add( Word("six", "temmokka"));

    words.add( Word("seven", "kenekaku"));

    words.add( Word("eight", "kawinta"));

    words.add( Word("nine", "wo’e"));

    words.add( Word("ten", "na’aacha"));



    val adapter = WordAdapter(this,words)



    val listView = findViewById(R.id.list) as ListView?



    listView!!.setAdapter(adapter)

    }

}

The WordAdapter.kt file:-

package com.example.android.miwok



    import android.view.View

    import android.view.ViewGroup

    import android.widget.ArrayAdapter

    import android.app.Activity

    import android.content.Context

    import android.widget.TextView

    import android.view.LayoutInflater





    class WordAdapter : ArrayAdapter<Word>() {



        fun WordAdapter(context: Activity, words: ArrayList<Word>){

            super.ArrayAdapter<Word>(context, 0, words)

        }



        override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {

            // Check if the existing view is being reused, otherwise inflate the view

            var listItemView = convertView

            if (listItemView == null) {

                listItemView = LayoutInflater.from(context).inflate(

                        R.layout.list_item, parent, false)

            }



            val currentWord = getItem(position)



            val nameTextView = listItemView!!.findViewById(R.id.miwok_text_view) as TextView



            nameTextView.setText(currentWord!!.getDefaultTranslation())



            val numberTextView = listItemView.findViewById(R.id.default_text_view) as TextView



            numberTextView.setText(currentWord!!.getMiwokTranslation())



            return listItemView

        }

    }

I am not able to find the error in this.

The word super should be linked to which part is also confusable to me.

There are a few things you can improve upon:

You are currently writing Javlin, or Kotva, i.e. a mix of Java and Kotlin.

You should not be inflating the layout for every getView, and you should ideally be using the ViewHolder pattern (now shown below).

But the reason for your question, the compiler error calling super. You are defining your constructor as a function, not a constructor.

In Java constructors are defined by writing methods with the same name as the class. In Kotlin you just pass the constructor parameters in the class definition. e.g.

class WordAdapter(context: Context, objects: List<Word>)

and pass those parameters through to the extended class as such:

class WordAdapter(context: Context, objects: List<Word>) :

    ArrayAdapter<Word>(context, R.layout.list_item, R.id.default_text_view, objects) 

an alternative approach, usually reserved for secondary constructors:

class WordAdapter : ArrayAdapter<Word> {  

    constructor(context: Context, objects: List<Word>) : super(

        context, R.layout.list_item, R.id.default_text_view, objects

    )

}

Here is a somewhat Kotlinified version of your code (I saw that you were swapping default and miwok in your getView, I assumed that was a mistake and did not copy that). I've also put a copy up on Github.

class MainActivity : AppCompatActivity() {



    private val words = arrayListOf(

        Word("one", "lutti"),

        Word("two", "otiiko"),

        Word("three", "tolookosu"),

        Word("four", "oyyisa"),

        Word("five", "massokka"),

        Word("six", "temmokka"),

        Word("seven", "kenekaku"),

        Word("eight", "kawinta"),

        Word("nine", "wo’e"),

        Word("ten", "na’aacha")

    )



    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)

        setContentView(R.layout.activity_main)



        val listView = findViewById<ListView>(R.id.list)

        val adapter = WordAdapter(this, words)



        listView.adapter = adapter

    }

}



data class Word(val defaultTranslation: String, val miwokTranslation: String)



class WordAdapter(context: Context, objects: List<Word>) :

    ArrayAdapter<Word>(context, R.layout.list_item, R.id.default_text_view, objects) {



    override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {

        val listItemView = super.getView(position, convertView, parent)

        val defaultTextView = listItemView.findViewById<TextView>(R.id.default_text_view)

        val miwokTextView = listItemView.findViewById<TextView>(R.id.miwok_text_view)



        getItem(position)?.run {

            defaultTextView.text = defaultTranslation

            miwokTextView.text = miwokTranslation

        }

        return listItemView

    }

}

Here is an example adapter using (a version of) the ViewHolder pattern (if you put a logging breakpoint on any of the row.findViewByIds you will see they are only called for as many items as are being displayed, not for every item in the list):

class WordAdapter(context: Context, objects: List<Word>) :

    ArrayAdapter<Word>(context, R.layout.list_item, R.id.default_text_view, objects) {



    class ViewHolder(row: View) {

        init {

            row.tag = this

        }



        val defaultTextView = row.findViewById<TextView>(R.id.default_text_view)!!

        val miwokTextView = row.findViewById<TextView>(R.id.miwok_text_view)!!

    }



    override fun getView(position: Int, convertView: View?, parent: ViewGroup): View {

        val listItemView = super.getView(position, convertView, parent)



        val holder = listItemView.tag as? ViewHolder ?: ViewHolder(listItemView)



        getItem(position)?.run {

            holder.defaultTextView.text = defaultTranslation

            holder.miwokTextView.text = miwokTranslation

        }



        return listItemView

    }

}

If you want to go overboard [:)] with Kotlin idioms:

override fun getView(position: Int, convertView: View?, parent: ViewGroup): View =

    super.getView(position, convertView, parent).also { row ->

        (row.tag as? ViewHolder ?: ViewHolder(row)).apply {

            getItem(position)?.run {

                defaultTextView.text = defaultTranslation

                miwokTextView.text = miwokTranslation

            }

        }

    }