android - Android 加载带有进度对话框的列表视图

Question

这是我加载列表视图项目的代码

  @SuppressLint("DefaultLocale")
   public class SearchList extends Activity {

  private ArrayList<String> founded = new ArrayList<String>();
  private OrderAdapter m_adapter;


ListView lv;

/** Called when the activity is first created. */
@SuppressLint("DefaultLocale")
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.searchlist);
    lv = (ListView) findViewById(R.id.listView1);

    new Load().execute();

    m_adapter = new OrderAdapter(this, R.layout.itemview, founded);

    lv.setAdapter(m_adapter);
    lv.setTextFilterEnabled(true);
    }

  private class Load extends AsyncTask<Void, Void, Void> {

    ProgressDialog progress;

    @Override
    protected void onPreExecute() {
        progress = new ProgressDialog(SearchList.this);
        progress.setMessage("loading....");
        progress.show();
    }

    @Override
    protected Void doInBackground(Void... params) {
             try {

            for (int i = 0; i <500000; i++) {
             founded.add("String "+i);
               }

        } catch (Exception e) {

        }
            return null;
    }

    @Override
    protected void onPostExecute(Void result) {

        // write display tracks logic here
        progress.dismiss(); // dismiss dialog
    }
}

当我运行代码时，进度对话框已经出现但是在它关闭后我发现列表是空的，没有添加任何项目我不知道问题是什么以及为什么在对话框加载后列表是空的。请需要帮助谢谢进步。

Answer 1

设置 listadapteronPostExecute因为您AsyncTask用于获取适配器数据并在完成 AsyncTask 之前设置 ListAdapter 所以尝试在完成 AsyncTask 之后设置 ListAdapter
所以添加这些

 m_adapter = new OrderAdapter(this, R.layout.itemview, founded);
lv.setAdapter(m_adapter);
lv.setTextFilterEnabled(true);

方法中的行onPostExecute而不是onCreate方法

 @Override
    protected void onPostExecute(Void result) {

        // write display tracks logic here
        progress.dismiss(); // dismiss dialog
     m_adapter = new OrderAdapter(YourActivity.this, R.layout.itemview, founded);
     lv.setAdapter(m_adapter);
     lv.setTextFilterEnabled(true);
    }