错误无法使用 list.setAdapter（适配器）解析符号列表

Question

这是我的代码，它以 100% 的速度运行：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View inflatedView = inflater.inflate(R.layout.t1, container, false);
    final ListView list = (ListView) inflatedView.findViewById(R.id.list);
    class json extends AsyncTask<String,String, List<MovieModel> > {
        ...
        @Override
        protected void onPostExecute(final List<MovieModel> result) {
            ...
            MainActivity.Adapter adapter = new MainActivity.Adapter(getActivity().getApplicationContext(), R.layout.row, result);
            list.setAdapter(adapter);
            list.setOnItemClickListener
            ...
        }
}

但现在我也需要在另一个位置调用 json class:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
....
class json .....
 }

@Override
public void onRefresh() {
    new json();// i can't recall in this way, but i need it
}

问题出在列表上，因为我无法从 onCreateView 中退出，因为如果我这样做，列表不确定。

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    ....
    new json();
}
class json extends AsyncTask<String,String, List<MovieModel> > {
    ...
    @Override
    protected void onPostExecute(final List<MovieModel> result) {
        ...
        MainActivity.Adapter adapter = new MainActivity.Adapter(getActivity().getApplicationContext(), R.layout.row, result);
        list.setAdapter(adapter);//this is an error now

现在的错误是"cannot resolve simbol 'list'"。

Answer 1

快速解决方案是将 list 设为 class 变量。

public class MainActivty extends Activity {
    private ListView mList;

    private class json extends AsyncTask<String,String, List<MovieModel> > {
        ...
        @Override
        protected void onPostExecute(final List<MovieModel> result) {
        ...
        mList.setAdapter(adapter);
        ...
    }
}

但更好的解决方案是将 result 从 onPostExecute 传回 MainActivity 以更新 UI。

public class MainActivty extends Activity {
    private ListView mList;

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View inflatedView = inflater.inflate(R.layout.t1, container, false);
        mList = (ListView) inflatedView.findViewById(R.id.list);
        ...
    }

    private void updateUI(final List<MovieModel> result> {
        MainActivity.Adapter adapter 
            = new MainActivity.Adapter(getActivity().getApplicationContext(), R.layout.row, result);
        mList.setAdapter(adapter);
        ...
    }

    private class json extends AsyncTask<String,String, List<MovieModel> > {
        ...
        @Override
        protected void onPostExecute(final List<MovieModel> result) {
        ...
        updateUI(result);
        ...
    }
}

通过这种方式，您可以在 AsyncTask 中保留所有数据处理，在 Activity 中保留所有 UI 处理。

错误无法使用 list.setAdapter（适配器）解析符号列表

Error cannot resolve simbol list with list.setAdapter(adapter)

android

oncreate

android-fragments