public ArrayList<modelListprod> listadeprod;
public static AdapterProd itensprod;
private ListView listproduto;

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView( layout.activity_main);
        layoutContentMain = (ConstraintLayout)findViewById( id.layoutContentMainMenu);
        conectarBanc();
        selecionaemitente(conexao);

        listadeprod = new ArrayList<modelListprod>();
        itensprod = new AdapterProd(this, listadeprod);

        listproduto = (ListView) findViewById(id.listproduto);
        listproduto.setAdapter(itensprod);

    }

public void atualizalistaprod(){
        itensprod.notifyDataSetChanged();
    }



public void lprod(SQLiteDatabase db){
        ArrayList<modelListprod> prod = new ArrayList<modelListprod>();

        //Passa para dentro do while
        //listprod = new modelListprod();

        String descricao = "";
        String ean = "";
        String status = "";
        Double precoprod;
        String categoria;
        int cod;

        final SQLiteDatabase d5 = dadosOpenHelper.getReadableDatabase();
        final Cursor cursor5 = d5.query("produto" , new String[]{"descricao", "ean", "status", "precoprod", "codigocateg", "cod"},null, null, null   ,null,null,null);
        if (cursor5 != null) {
            if (cursor5.moveToFirst()) {

                do {

                    //uma nova instância por cada registo
                    listprod = new modelListprod();

                    descricao = cursor5.getString(0);
                    ean = cursor5.getString(1);
                    status = cursor5.getString(2);
                    precoprod = cursor5.getDouble(3);
                    categoria = cursor5.getString(4);
                    cod = cursor5.getInt(5);
                    listprod.setDescricao(descricao);
                    listprod.setCategoria(categoria);
                    listprod.setEan(ean);
                    listprod.setPreco(precoprod);
                    listprod.setStatus(status);
                    listprod.getId(cod);

                    //Adiciona ao array
                    listadeprod.add(listprod);

                } while (cursor5.moveToNext());
            }

            listproduto.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    modelListprod c = (modelListprod) parent.getItemAtPosition(position);
                    Intent intent = new Intent(getApplicationContext(), AlteraProd.class);
                    intent.putExtra("Dados", (Serializable) c);
                    startActivity(intent);
                }
            });
        }
        itensprod.notifyDataSetChanged();
        //Passa para dentro do while
        //listadeprod.add(listprod);

        AdapterProd adapterProd = new AdapterProd(this, listadeprod);
        listproduto.setAdapter(adapterProd);
    }

public class AdapterProd extends ArrayAdapter<modelListprod> {

    MainActivity m = new MainActivity();

    private Context context;
    private ArrayList<modelListprod> lista;



    public AdapterProd(Context context, ArrayList<modelListprod> lista){
        super(context, 0, lista);
        this.context = context;
        this.lista = lista;


    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
       final modelListprod itemposicao = this.lista.get(position);

        if(convertView == null){
            convertView = LayoutInflater.from(this.context).inflate(R.layout.list_prod, null);
        }

        TextView textView1 = (TextView) convertView.findViewById(R.id.tvdescricao2);
        textView1.setText(itemposicao.getDescricao());

        TextView textView2 = (TextView) convertView.findViewById(R.id.tvcategoria2);
        textView2.setText(itemposicao.getCategoria());

        TextView textView3 = (TextView) convertView.findViewById(R.id.tvpreco2);
        textView3.setText(itemposicao.getPreco().toString());

        TextView textView4 = (TextView) convertView.findViewById(R.id.tvean2);
        textView4.setText(itemposicao.getEan());

        TextView textView5 = (TextView) convertView.findViewById(R.id.tvstatus2);
        textView5.setText(itemposicao.getStatus());

        Button grava = (Button) convertView.findViewById( R.id.gravaalteraprod );
        grava.setOnClickListener( new View.OnClickListener() {


            public void onClick(View v) {
                itemposicao.setDescricao( itemposicao.getDescricao());
                itemposicao.setCategoria( itemposicao.getCategoria());
                itemposicao.setPreco( itemposicao.getPreco());
                itemposicao.setEan( itemposicao.getEan());
                itemposicao.setStatus( itemposicao.getStatus());
                m.atualizalistaprod();

            }
        } );



        return convertView;
    }
}