Save state of a CheckBox

I need to save the state of my CheckBox, they are inside a Spinner, and every time I open the Spinner it clears the CheckBox.

AdmList.java

        final String[] select_qualification = {
                "Todos", "1", "2", "3", "4",
                "5", "6"};
        Spinner spinner = (Spinner) findViewById(R.id.spinner);

        ArrayList<StateVO> listVOs = new ArrayList<>();

        for (int i = 0; i < select_qualification.length; i++) {
            StateVO stateVO = new StateVO();
            stateVO.setTitle(select_qualification[i]);
            stateVO.setSelected(false);
            listVOs.add(stateVO);
        }
        MyAdapter myAdapter = new MyAdapter(AdmListagem.this, 0,
                listVOs);
        spinner.setAdapter(myAdapter);

spinner_item2.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/text"
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="25dp"
        android:paddingTop="10dp"
        android:paddingRight="10dp"
        android:paddingBottom="10dp"
        android:textSize="16dp"
        android:textColor="#000000"
        android:background="@drawable/spinner_item_border" />

    <CheckBox
        android:id="@+id/checkbox"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentEnd="true"
        android:layout_alignParentRight="true" />
</RelativeLayout>

MyAdapter.java

public class MyAdapter extends ArrayAdapter<StateVO>  {
    private Context mContext;
    private ArrayList<StateVO> listState;
    private MyAdapter myAdapter;
    private boolean isFromView = false;
    String[] values;
    Boolean[] checkedStatus;

    public MyAdapter(Context context, int resource, List<StateVO> objects) {
        super(context, resource, objects);
        this.mContext = context;
        this.listState = (ArrayList<StateVO>) objects;
        this.myAdapter = this;
    }

    @Override
    public View getDropDownView(int position, View convertView,
                                ViewGroup parent) {
        return getCustomView(position, convertView, parent);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        return getCustomView(position, convertView, parent);
    }

    public View getCustomView(final int position, View convertView,
                              ViewGroup parent) {

        final ViewHolder holder;
        if (convertView == null) {
            LayoutInflater layoutInflator = LayoutInflater.from(mContext);
            convertView = layoutInflator.inflate(R.layout.spinner_item2, null);
            holder = new ViewHolder();
            holder.mTextView = (TextView) convertView
                    .findViewById(R.id.text);
            holder.mCheckBox = (CheckBox) convertView
                    .findViewById(R.id.checkbox);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        holder.mTextView.setText(listState.get(position).getTitle());

        // To check weather checked event fire from getview() or user input
        isFromView = true;
        holder.mCheckBox.setChecked(listState.get(position).isSelected());
        isFromView = false;

        if ((position == 0)) {
            holder.mCheckBox.setVisibility(View.INVISIBLE);
        } else {
            holder.mCheckBox.setVisibility(View.VISIBLE);
        }
        holder.mCheckBox.setTag(position);
        holder.mCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                int getPosition = (Integer) buttonView.getTag();
                String t = String.valueOf(getPosition);
                Toast.makeText(mContext, t, Toast.LENGTH_SHORT).show();

            }
        });
        return convertView;
    }

    private class ViewHolder {
        private TextView mTextView;
        private CheckBox mCheckBox;
    }
}

Statevo.java

public class StateVO {
    private String title;
    private boolean selected;

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public boolean isSelected() {
        return selected;
    }

    public void setSelected(boolean selected) {
        this.selected = selected;
    }
}

When you run the application and in Spinner choose the items, and click on the screen, and open the Spinner again it is without any CheckBox marking