android - 更新传递给适配器的列表对象以创建 GridView

Question

我正在尝试更新已传递给适配器的列表对象的内容，以便创建 GridView。这是代码:

 public class GameActivity extends Activity {
List<String> nums;
GridView sudoku_grid;
ArrayAdapter<String> adapter;
@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_temp);
    sudoku_grid=(GridView)findViewById(R.id.sudoku_grid);
    nums= Arrays.asList("1","2","3","5","7","8","2","3","1","9","3","3","1");
    adapter=new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,nums);
    sudoku_grid.setAdapter(adapter);
}

    public void trial(View view)
    {
        Runnable r=new Runnable() {
            @Override
            public void run() {
                nums.add("7");
                adapter.notifyDataSetChanged();
            }};
        new Thread(r).start();
    }

每次单击按钮时都会执行 trial()。一旦 trial() 中的线程启动，它不会更新内容，而是会启动上一个 Activity 。谁能告诉我哪里出错了？

Answer 1

您需要通过 nums对象再次到适配器。创建 class那extends ArrayAdapter<String>如下:

class MyArrayAdapter extends ArrayAdapter<String>{

    List<String> nums;

    public MyArrayAdapter(Context context,int itemID,List<String> nums){
        this.nums=nums;
    }

    @ovverride
    public int getCount() {
        return nums.size();
    }

    public void changeObjects(List<String> nums){
        this.nums=nums;
        this.notifyDataSetChanged();
    }

    public View getView(int position, View convertView, ViewGroup parent){
        //.... Implement own code
    }

}

如果还有其他问题或疑问，请告诉我。