Kotlin - RecyclerView.LayoutManager 问题

Question

I'm learning Kotlin & Adroid Studio and recently I have stuck on RecyclerView .

The problem is that I'm not able to go forward due to error showing on LayoutManager .

My little code looks like:

 package com.example.julian.recyclerviewapplication

import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.support.v7.widget.LinearLayoutManager
import android.support.v7.widget.RecyclerView

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        RecyclerView.LayoutManager=LinearLayoutManager(this)

    }
}

LayoutManager is underlined and tells me that: "

Classifier 'LayoutManager' does not have a companion object, and thus must be initalized here".

I'm not a advanced programist, rather a newbie and I've been trying to fix this remark but at this moment its beyond my skills.

Thank you for your help.

Answer 1

val layoutManager = LinearLayoutManager(this)
<your recyclerview>.layoutManager = layoutManager

Or even shorter:

<your recyclerview>.layoutManager = LinearLayoutManager(this)

Answer 2

You can do like below:

my_recyclerview_id.layoutManager = LinearLayoutManager(this);

Here "my_recyclerview_id" is your recyclerview id from your layout XML file.

Answer 3

Try this 1st way

val layoutManager = LinearLayoutManager(applicationContext)
your_recyclerview_id!!.layoutManager = layoutManager
your_recyclerview_id!!.adapter = Your_adapter(applicationContext)

2nd way

 your_recyclerview_id!!.layoutManager=LinearLayoutManager(applicationContext)
 your_recyclerview_id!!.adapter = Your_adapter(applicationContext);
 your_recyclerview_id!!.adapter.notifyDataSetChanged()

Best of luck with Kotlin

Answer 4

No need to define 'findviewByID' in kotlin...Android understand by default all resource and View element.

you can try it...

Only use this code when you are working on RecycleView in kotlin

 rc_all_transaction.setLayoutManager(LinearLayoutManager(activity, 
   LinearLayoutManager.VERTICAL, true))

here rc_all_transaction is ID of Recycleview and rest is setting Layout Manager

Thanks

Answer 5

Tt should be RecyclerView.layoutManager = LinearLayoutManager(this) . Lower-case l and not upper-case L .