如何使用引用更多CONSTANT List <object>的变量List <object>

Question

1. 打开活动，列表中包含第一个listView。该列表是使用new ArrayList<>(Constants.FIRST)复制的常量列表的副本。

2. 我清除（活动）列表并使用list = new ArrayList(Constants.SECOND);引用第二个列表，通知适配器但是为空。

3. 返回第一个列表，列表再次为空。

这是我用过的代码

public class Activity extends AppCompatActivity{
    private List<Object> list; //tried also... = new ArrayList<>;
    private boolean boo;
    private ObjectAdapter adapter;
    @Override
    protected void onCreate(Bundle saveInstanceState) {
        super.onCreate(saveInstanceState);
        setContentView(R.layout.list_view);

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        ListView listView = (ListView) findViewById(R.id.list);
        list = new ArrayList<>(Constants.FIRST);
        adapter = new ObjectAdapter(this, list);
        listView.setAdapter(adapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (boo){
                   newIntent(position);
                }
                else {
                    secondList(position);
                }
            }
        });
    }
public void newIntent(int position){
        startActivity(new Intent(this, Activity2.class);
    }

    public void secondList(int position){
        list.clear();
        list = new ArrayList<>(Constants.SECOND);
        adapter.notifyDataSetChanged();
        boo = true;
    }

    @Override
    public void onBackPressed() {
        if (boo) {list.clear(); list = new ArrayList<>(Constants.FIRST); adapter.notifyDataSetChanged(); boo=false;}
        else {finish();}
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                onBackPressed();
                return true;
        }

        return (super.onOptionsItemSelected(item));
    }
}

这是常量列表

public interface Constants {

    List<Object> FIRST= new ArrayList<Object>(){{
        add (new Object(0, 1, "Good"));
        add (new Object(1, 1, "Ok"));

    List<Object> SECOND= new ArrayList<Object>(){{
        add (new Object(0, 2, "First"));
        add (new Object(1, 2, "Second"));