MainActivity.java

package com.example.aluno_uffs.myapplication;

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;


//class MeuListener implements View.OnClickListener {
//
//    ArrayAdapter adapter;
//
//    MeuListener(ArrayAdapter<String> adapter) {
//        this.adapter = adapter;
//    }
//
//    @Override
//    public void onClick(View v) {
//        adapter.add("Sim, claro!");
//    }
//}


public class MainActivity extends AppCompatActivity {




    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ListView lista = findViewById(R.id.lista);
        Button button = findViewById(R.id.adicionar);


        ArrayList<String> meuArray = new ArrayList<String>();

        final ArrayAdapter<String> adapter =
                new ArrayAdapter<String>(this,
                        android.R.layout.simple_list_item_1, meuArray);

        adapter.add("oi");
        adapter.add("tudo bem?");

        lista.setAdapter(adapter);

        //MeuListener listener = new MeuListener(adapter);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                adapter.add("Sim, claro!");
            }
        });


    }
}