Adapter in a Listview in Android Studio

Question

I’m trying to complement a code that controls a custom Listview, through three classes: AdapterListView, ItemListView and the MainActivity.

So far, the code only manages the insertion of data and images (inserted via code) through the AdapterListView. Within this same class, I would like to know how I use other features, such as adding or removing items by the application itself.

Below the three project classes:

Adapterlistview

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.ArrayList;

/**
* Created by LuizHMU on 2/7/15.
*/
public class AdapterListView extends BaseAdapter {

private LayoutInflater mInflater;
private ArrayList<ItemListView> itens;

public AdapterListView(Context context, ArrayList<ItemListView> itens) {
    //Itens que preencheram o listview
    this.itens = itens;
    //responsavel por pegar o Layout do item.
    mInflater = LayoutInflater.from(context);
}

/**
 * Retorna a quantidade de itens
 *
 * @return
 */
public int getCount() {
    return itens.size();
}

/**
 * Retorna o item de acordo com a posicao dele na tela.
 *
 * @param position
 * @return
 */
public ItemListView getItem(int position) {
    return itens.get(position);
}

/**
 * Sem implementação
 *
 * @param position
 * @return
 */
public long getItemId(int position) {
    return position;
}

public View getView(int position, View view, ViewGroup parent) {
    //Pega o item de acordo com a posção.
    ItemListView item = itens.get(position);
    //infla o layout para podermos preencher os dados
    view = mInflater.inflate(R.layout.item_list, null);

    //atravez do layout pego pelo LayoutInflater, pegamos cada id relacionado
    //ao item e definimos as informações.
    ((TextView) view.findViewById(R.id.text)).setText(item.getTexto());
    ((ImageView) view.findViewById(R.id.imagemview)).setImageResource(item.getIconeRid());

    return view;
}
}

Itemlistview

/**
* Created by LuizHMU on 2/7/15.
*/
public class ItemListView {

private String texto;
private int iconeRid;

public ItemListView() {
}

public ItemListView(String texto, int iconeRid) {
    this.texto = texto;
    this.iconeRid = iconeRid;
}

public int getIconeRid() {
    return iconeRid;
}

public void setIconeRid(int iconeRid) {
    this.iconeRid = iconeRid;
}

public String getTexto() {
    return texto;
}

public void setTexto(String texto) {
    this.texto = texto;
}
}

Mainactivity

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;

public class MainActivity extends Activity implements OnItemClickListener {

private ListView listView;
private AdapterListView adapterListView;
private ArrayList<ItemListView> itens;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    //carrega o layout onde contem o ListView
    setContentView(R.layout.activity_main);

    //Pega a referencia do ListView
    listView = (ListView) findViewById(R.id.list);
    //Define o Listener quando alguem clicar no item.
    listView.setOnItemClickListener(this);

    createListView();
}

private void createListView() {
    //Criamos nossa lista que preenchera o ListView
    itens = new ArrayList<ItemListView>();
    ItemListView item1 = new ItemListView("Felpudo", R.drawable.felpudo);
    ItemListView item2 = new ItemListView("Felpudão", R.drawable.felpudo1);
    ItemListView item3 = new ItemListView("Felpudinho", R.drawable.felpudo2);

    itens.add(item1);
    itens.add(item2);
    itens.add(item3);

    //Cria o adapter
    adapterListView = new AdapterListView(this, itens);

    //Define o Adapter
    listView.setAdapter(adapterListView);
    //Cor quando a lista é selecionada para ralagem.
    listView.setCacheColorHint(Color.TRANSPARENT);
}

public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
    //Pega o item que foi selecionado.
    ItemListView item = adapterListView.getItem(arg2);
    //Demostração
    Toast.makeText(this, "Você Clicou em: " + item.getTexto(), Toast.LENGTH_LONG).show();
}
}

Answer 1

The ideal solution would be to add one more item in the ArrayList<ItemListView> itens

and soon after you run the Adapter notifyDataSetChanged method to update the information from listview onscreen.

adapterListView.notifyDataSetChanged();

For a better answer I need to know how your item registration form will be, if it will be in a Activity new or in the same.