Bundle之间发送ArrayList<Integer>

Question

问题：
如何将_selectednumber和_points的数据从onSaveInstanceState转移到onRestoreInstanceState？

private List<Integer> _selectednumber= new ArrayList<>();
private List<Integer> _points = new ArrayList<>();
private int _hit= 0;
private int _round = 1;


protected void onSaveInstanceState(Bundle out)
{
    super.onSaveInstanceState(out);

    out.putInt("p_hit", _hit);
    out.putInt("p_round", _round );
}


@Override
protected void onRestoreInstanceState(Bundle in)
{
    super.onRestoreInstanceState(in);

    _hit = in.getInt("p_hit");
    _round = in.getInt("p_round");
}

Answer 1

以下应该适合您：

protected void onSaveInstanceState(Bundle out) {
    super.onSaveInstanceState(out);
    out.putInt("p_hit", _hit);
    out.putInt("p_round", _round);
    out.getIntegerArrayList("_selectednumber");
    out.getIntegerArrayList("_points");
}


@Override
protected void onRestoreInstanceState(Bundle in) {
    super.onRestoreInstanceState(in);
    _hit = in.getInt("p_hit");
    _round = in.getInt("p_round");
    _selectednumber = in.getIntegerArrayList("_selectednumber");
    _points = in.getIntegerArrayList("_points");
}

Answer 2

您可以使用 putIntegerArrayList() 存储数据，并使用 getIntegerArrayList() 检索数据。但是，您已将变量声明为 List<Integer>，这不满足 putIntegerArrayList().

的要求

你有两个选择。首先，您可以更改声明变量的方式，使它们显式 ArrayLists，而不仅仅是 Lists:

private ArrayList<Integer> _selectednumber= new ArrayList<>();
private ArrayList<Integer> _points = new ArrayList<>();
private int _hit= 0;
private int _round = 1;

protected void onSaveInstanceState(Bundle out)
{
    super.onSaveInstanceState(out);

    out.putInt("p_hit", _hit);
    out.putInt("p_round", _round );
    out.putIntegerArrayList("p_selectednumber", _selectednumber);
    out.putIntegerArrayList("p_points", _points);
}

@Override
protected void onRestoreInstanceState(Bundle in)
{
    super.onRestoreInstanceState(in);

    _hit = in.getInt("p_hit");
    _round = in.getInt("p_round");
    _selectednumber = in.getIntegerArrayList("p_selectednumber");
    _points = in.getIntegerArrayList("p_points");
}

或者，当您尝试将 List 实例放入包中时，您可以用 new ArrayList<>() 包装它们：

private List<Integer> _selectednumber= new ArrayList<>();
private List<Integer> _points = new ArrayList<>();
private int _hit= 0;
private int _round = 1;

protected void onSaveInstanceState(Bundle out)
{
    super.onSaveInstanceState(out);

    out.putInt("p_hit", _hit);
    out.putInt("p_round", _round );
    out.putIntegerArrayList("p_selectednumber", new ArrayList<>(_selectednumber));
    out.putIntegerArrayList("p_points", new ArrayList<>(_points));
}

@Override
protected void onRestoreInstanceState(Bundle in)
{
    super.onRestoreInstanceState(in);

    _hit = in.getInt("p_hit");
    _round = in.getInt("p_round");
    _selectednumber = in.getIntegerArrayList("p_selectednumber");
    _points = in.getIntegerArrayList("p_points");
}

Bundle之间发送ArrayList<Integer>

Send ArrayList<Integer> between Bundle

android

onrestoreinstancestate

onsaveinstancestate