Android Kotlin - RecyclerView

Afluentes Dispositivos Móveis

Interface

• Crie uma Activity Empty com:
  • LinearLayout
    • 2 campos PlainText (textName e textPhone)
    • 1 botão (button)
    • 1 TextView ("Lista de Contatos")
    • 1 RecyclerView (listRecycler)

• Crie um layout chamado contact.xml com:
  • 2 TextView (list_nome, list_phone)
  • configure o layout_width para match_parent
  • configure o layout_height para warp_content

Classe Contact.kt

package com.example.myapplication

class Contact(val name : String, val phone : String)

Classe MyAdapter.kt

package com.example.myapplication

import android.content.Context
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.recyclerview.widget.RecyclerView

class AdapterContato(
    private val context: Context,
    private val list: List<Contact>

) : RecyclerView.Adapter<AdapterContato.ViewHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup, p1: Int): ViewHolder {
        val view = LayoutInflater.from(context).inflate(
            R.layout.contact, parent, false

        )
        return ViewHolder(view)
    }

    override fun getItemCount(): Int {
        return list.size
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val item = list[position]
        holder.name.text = item.name;
        holder.phone.text = item.phone;
    }

    class ViewHolder(itemView: View) :
        RecyclerView.ViewHolder(itemView) {
        val name: TextView = itemView.findViewById(R.id.list_name)
        val phone: TextView = itemView.findViewById(R.id.list_phone)
    }
}

Classe MainActivity.kt

package com.example.myapplication

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {

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

        val name : EditText = findViewById(R.id.editTextName)
        val phone : EditText = findViewById(R.id.editTextPhone)
        val button : Button = findViewById(R.id.button)
        val listRecycler : RecyclerView = findViewById(R.id.recyclerView)

        val list = ArrayList<Contact>()
        val layoutManager = LinearLayoutManager(this)
        listRecycler.layoutManager = layoutManager
        val adapter = AdapterContato(this, list)
        listRecycler.adapter = adapter

        button.setOnClickListener {
            list.add(Contact(name.text.toString(), phone.text.toString()))
            adapter.notifyDataSetChanged()
            name.text.clear()
            phone.text.clear()
        }
    }
}

Exercício

Colocar ações de clicar num elemento e jogar as informações nos campos e longo clique exclui elemento.