Question

当列表为空时，我的ListView未显示空视图。这是我的Fragment代码和Layout。

public class ViewSearchClientFragment extends BaseFragment implements
        OnItemClickListener {
    ArrayList<ClientDetails> clientArrayList;
    ListView lvClientList;
    ClientListAdapter adapter;
    ServerDetails serverDetails;
    long totalresult = 0;
    int totalpages = 0;

    Boolean flag_loading = false;

    EditText etTerm;
    TextView tvEmpty;

    private int limitstart = 0;
    private int limitnum = 30;
    private int totalresults;
    private int numreturned = 0;

    public static ViewSearchClientFragment newInstance(int groupPosition,
            int ChildPosition) {
        ViewSearchClientFragment fragment = new ViewSearchClientFragment();
        Bundle args = new Bundle();
        args.putInt("group_position", groupPosition);
        args.putInt("child_position", ChildPosition);
        args.putString("title", "View/Search Clients");
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_view_search_clients,
                container, false);

        lvClientList = (ListView) rootView.findViewById(R.id.lvClients);
        /*
         * lvClientList.addHeaderView(View.inflate(mActivity,
         * R.layout.client_listview_header, null));
         */
        tvEmpty = (TextView) rootView.findViewById(android.R.id.empty);
        tvEmpty.setText("");

        clientArrayList = new ArrayList<ClientDetails>();
        adapter = new ClientListAdapter(mActivity, clientArrayList);

        lvClientList.setAdapter(adapter);
        lvClientList.setEmptyView(tvEmpty);
        lvClientList.setOnItemClickListener(this);
        registerForContextMenu(lvClientList);
        lvClientList.setOnScrollListener(new OnScrollListener() {

            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {

            }

            @Override
            public void onScroll(AbsListView view, int firstVisibleItem,
                    int visibleItemCount, int totalItemCount) {

                if (firstVisibleItem + visibleItemCount == totalItemCount
                        && totalItemCount != 0) {
                    if (!flag_loading) {

                        if ((limitstart + numreturned) < totalresults) {
                            limitstart += limitnum;
                            getClients(null);
                        }
                    }
                }

            }
        });
        serverDetails = new ServerDetails(mActivity);
        getClients(null);
        return rootView;
    }



    int positionLongClick;


    private void getClients(final String[] params) {

        flag_loading = true;
        ProgressDialogManager.showDialog(mActivity);
        Response.Listener<JSONObject> responseListner = new Response.Listener<JSONObject>() {

            @Override
            public void onResponse(JSONObject arg0) {
                // TODO Auto-generated method stub

                try {
                    JSONObject jobj = arg0;
                    String result = jobj.getString("result");
                    if (result.contains("success")) {
                        totalresults = Integer.parseInt(jobj
                                .getString("totalresults"));
                        limitstart = Integer.parseInt(jobj
                                .getString("startnumber"));
                        numreturned = Integer.parseInt(jobj
                                .getString("numreturned"));

                        JSONObject temp = jobj.getJSONObject("clients");
                        JSONArray array = temp.getJSONArray("client");
                        for (int i = 0; i < array.length(); i++) {
                            JSONObject tempobject = array.getJSONObject(i);
                            ClientDetails detail = new ClientDetails();
                            clientArrayList.add(detail);
                            detail.name = (tempobject.getString("firstname")
                                    + " " + tempobject.getString("lastname"));
                            detail.id = Integer.parseInt((tempobject
                                    .getString("id")));
                            detail.company = (tempobject
                                    .getString("companyname"));
                            detail.email = (tempobject.getString("email"));
                            detail.status = (tempobject.getString("status"));
                        }

                    } else if (result.contains("error")) {
                        ProgressDialogManager.hideDialog();
                        Dialog d = new Dialog(mActivity,
                                jobj.getString("message"));
                        d.show();

                        return;
                    }
                } catch (JSONException e) {
                    // TODO Auto-generated catch block
                    ProgressDialogManager.hideDialog();
                    e.printStackTrace();
                    return;

                }
                tvEmpty.setText("No Client Found");
                tvEmpty.setVisibility(View.VISIBLE);
                ProgressDialogManager.hideDialog();
                adapter.notifyDataSetChanged();
                flag_loading = false;

            }
        };

        JsonObjectRequest request = new JsonObjectRequest(Method.POST,
                serverDetails.getUrl(), null, responseListner,
                MyErrorListner.getListnerEmptyView(mActivity, tvEmpty,
                        "No Client Found")) {

            @Override
            public String getBodyContentType() {
                // TODO Auto-generated method stub
                return "application/x-www-form-urlencoded";
            }

            @Override
            public byte[] getBody() {
                Uri.Builder builder = serverDetails.getBodyBuilder();
                builder.appendQueryParameter("action", "getclients");
                if (params != null) {
                    builder.appendQueryParameter("search", params[0]);
                }
                builder.appendQueryParameter("limitstart", limitstart + "");
                builder.appendQueryParameter("limitnum", limitnum + "");
                return builder.build().getEncodedQuery().getBytes();
            }
        };
        AppController.getInstance().addToRequestQueue(request);
    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {


    }



}

这是Layout。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/gradiant_background"
    android:orientation="vertical" >

    <EditText
        android:id="@+id/etFilterTerm"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="8dp"
        android:hint="Search Client"
        android:imeOptions="actionSearch"
        android:inputType="text" 
        android:drawableLeft="@android:drawable/ic_menu_search"/>

    <ListView
        android:id="@+id/lvClients"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:divider="@null"
        android:dividerHeight="5dp"
        android:padding="8dp" />

    <TextView
        android:id="@android:id/empty"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:text="No Clients Found"
        android:textAppearance="@android:style/TextAppearance.Large"
        android:visibility="gone" />

</LinearLayout>

Answer 1

我可以看到两个可能的问题：

1）您的TextView（id == empty）可能隐藏在屏幕底部 - 设置ListView到View.GONE的可见性空

或者使用ListView.setEmptyView()从xml中删除TextView并以编程方式创建

TextView tvEmpty = new TextView(context); 
tvEmpty .setText(...);
lvClientList.setEmptyView(tvEmpty);

~~2）您搜索TextView就像~~

tvEmpty = (TextView) rootView.findViewById(android.R.id.empty);

android这是一个印刷错误 - 用
替换它
tvEmpty = (TextView) rootView.findViewById(R.id.empty);

<击>

Answer 2

在设置适配器

之前设置setEmptyView（）方法

Answer 3

getClients方法的catch块存在问题。该方法在异常时返回，并且存在静默异常。我从catch块中删除了return语句，解决了我的问题。

catch (JSONException e) {
                    // TODO Auto-generated catch block
                    ProgressDialogManager.hideDialog();
                    e.printStackTrace();

                }
                tvEmpty.setText("No Client Found");
                tvEmpty.setVisibility(View.VISIBLE);
                ProgressDialogManager.hideDialog();
                adapter.notifyDataSetChanged();
                flag_loading = false;

            }

列表为空时，不显示ListView空视图

3 个答案: