Question

我在Fragment中显示带有自定义适配器的listView时遇到问题，此代码在活动中有效，但不在我的片段中，当我运行代码时不显示任何错误。再次，此代码在活动中起作用，使用适配器正确显示listView，并显示从JsonObjectRequest获得的每个数据的Toast，但在Fragment中，不只显示listView，而是正确显示Toast。我将片段的背景色设置为红色，但是却显示了白色的屏幕和Toast。（对不起，我的英语不好。）

public class ComplaintsFragment extends Fragment {
ListView lstCategories;
private RequestQueue queue;
private String url="http://192.168.1.3:8000/api/tipos";
private ArrayAdapter<CategoriaModel> categoriaAdapter;
List<CategoriaModel> categories;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup 
container,@Nullable Bundle savedInstanceState) {
    final View view= inflater.inflate(R.layout.fragment_complaints, 
    container, false);
    queue=Volley.newRequestQueue(view.getContext());
    categories=new ArrayList<>();
    Toast.makeText(view.getContext(), "Hello you're Fragment", 
    Toast.LENGTH_SHORT).show();
    lstCategories=(ListView) view.findViewById(R.id.lstCategories);
    JsonObjectRequest jsonObjectRequest = new 
    JsonObjectRequest(Request.Method.GET, url, null, new 
    Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {
            try {
                JSONArray jsonArray = response.getJSONArray("data");
                for (int i = 0; i < jsonArray.length(); i++) {
                    JSONObject jsonObject = jsonArray.getJSONObject(i);
                    int idcategory=jsonObject.getInt("idcategory");
                    String name = jsonObject.getString("name");
                    String details= jsonObject.getString("details");
                    CategoriaModel category=new 
                    CategoriaModel(idcategory,name,details);
                    Toast.makeText(view.getContext(), 
                    category.toString(), Toast.LENGTH_SHORT).show();
                    categories.add(category);
                }
                categoriaAdapter=new 
                CategoriaAdapter(getActivity(), 
                android.R.layout.simple_list_item_1,categories);
                lstCategories.setAdapter(categoriaAdapter);
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
     }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {

        }
    });
    queue.add(jsonObjectRequest);
    return view;
 }
}

这是我的listView适配器

public class CategoriaAdapter extends ArrayAdapter<CategoriaModel> {
    public CategoriaAdapter(@NonNull Context context, int resource, @NonNull List<CategoriaModel> objects) {
        super(context, resource, objects);
    }

    @NonNull
    @Override
        public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
            CategoriaModel objItem=getItem(position);
            LayoutInflater inflater= (LayoutInflater)getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View contenedor=inflater.inflate(R.layout.item_category,parent,false);
            TextView lblNombre=contenedor.findViewById(R.id.lblNombre);
            TextView lblDescripcion=contenedor.findViewById(R.id.lblDescripcion);
            lblNombre.setText(objItem.getNombre());
            lblDescripcion.setText(objItem.getDescripcion());
            return contenedor;
    }
}

Answer 1

我替换了这个：

getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,new ComplaintsFragment()).commit();

与此：

getSupportFragmentManager().beginTransaction().replace(android.R.content,new ComplaintsFragment()).commit();

所有作品，问题已解决

不要在片段中显示带有自定义适配器的ListView

1 个答案: