Arraylist statico returns size 0 when I try to recover it in an Activity

Question

I have This class:

abstract public class ListaEstaticaDeErros {
private static ArrayList<DescritorDeErro> listErros = new ArrayList<DescritorDeErro>();
private static boolean fimSinc = false;
private static int municipio = 0;

public static boolean getFimSinc(){
    return fimSinc;
}

public static int getMunicipio(){
    return municipio;
}

public static void setMunicipio(int i){
    municipio = i;
}

public static void setFimSinc(boolean b){
    fimSinc = b;
}

public static void setListErros(ArrayList<DescritorDeErro> list){
    listErros = list;
}

public static void addRegListErros(DescritorDeErro obj){
    listErros.add(obj);
}

public static ArrayList<DescritorDeErro> getListErros(){
    return listErros;
}

}

Activity function that I try to recover and show the list size:

public void montarResultados(){
        Log.e("Teste-esus", String.valueOf(ListaEstaticaDeErros.getListErros().size()));
        Bundle bundle = getIntent().getExtras();
        ArrayList<DescritorDeErro> lst = bundle.getParcelableArrayList("lista");
        int mun = bundle.getInt("municipio");
        String usuario = bundle.getString("usuario");
        if(lst.size() > 0) {
            new ChargeList().execute(lst, mun, usuario);
        }else{
            txtVInfo.setText("Nenhum erro capturado ate este momento de sincronização.");
        }
        if(bundle.getBoolean("fim_sinc")) {
            txtEmail.setVisibility(View.VISIBLE);
        }else{
            txtEmail.setVisibility(View.INVISIBLE);
        }
    }

And inside an Activity I need to recover this listErros and it always returns me 0, ie without any element, but if I catch her in another class that is not an Activity I can without problems, then the solution I made was to pick her up in another class and send via Intent to the Activity I need, however I would like to take her directly from Activity to be able to implement what I need.

Answer 1

Create an interface like below, which will be able to recover the values of the listErros.

public interface Listaestaticadeerros {

Static Arraylist listErros = new Arraylist();

... }

Answer 2

You can do it like this:

    public class ListaEstaticaDeErros {
    private ArrayList<DescritorDeErro> listErros = new ArrayList<DescritorDeErro>();
    private boolean fimSinc = false;
    private int municipio = 0;

    private static ListaEstaticaDeErros instance;

    public static ListaEstaticaDeErros getInstance() {
        if (instance == null) {
            instance = new ListaEstaticaDeErros()
        }

        return instance;
    }

    public  boolean getFimSinc(){
        retmSinc;
    }

    public  int getMunicipio(){
        retnicipio;
    }

    public  void setMunicipio(int i){
        mun = i;
    }

    public  void setFimSinc(boolean b){
        fim b;
    }

    public  void setListErros(ArrayList<DescritorDeErro> list){
        lis = list;
    }

    public  void addRegListErros(DescritorDeErro obj){
        lis.add(obj);
    }

    public  ArrayList<DescritorDeErro> getListErros(){
        return listErros;
    }
}