Question

您好我是android的新手我在ListView中添加了一个搜索按钮，但是我得到了一个错误，你可以帮我解决这个错误。

修改

错误cannot resolve symbol adapter adapter是getuser方法中使用的List适配器

这是我的java代码

UserFragment.java

   public class UsersFragment extends Fragment implements ListView.OnItemClickListener {
private String JSON_STRING;
private ImageButton btn1;
public static final String URL = "http://10.0.3.2/GetPHP/getuser.php";
public static final String TAG_JSON_ARRAY = "result";
// List view
private ListView listView;
// Search EditText
EditText inputSearch;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View rootview = inflater.inflate(R.layout.fragment_users, container, false);
    listView  = (ListView)   rootview.findViewById(R.id.listView);
    inputSearch  = (EditText)   rootview.findViewById(R.id.inputSearch);
    listView.setOnItemClickListener(this);
    btn1=(ImageButton) rootview.findViewById(R.id.btn1);
    inputSearch.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
            // When user changed the Text
            (SimpleAdapter) UsersFragment .this.adapter.getFilter().filter(cs);
        }

        @Override
        public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
                                      int arg3) {
            // TODO Auto-generated method stub

        }

        @Override
        public void afterTextChanged(Editable arg0) {
            // TODO Auto-generated method stub
        }
    });
    getJSON();
    return rootview;
}

private void getuser(){
    JSONObject jsonObject = null;
    ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String, String>>();
    try {
        jsonObject = new JSONObject(JSON_STRING);
        JSONArray result = jsonObject.getJSONArray(TAG_JSON_ARRAY);

        for(int i = 0; i<result.length(); i++){
            JSONObject jo = result.getJSONObject(i);
            String name = jo.getString("Nom");
            String ref = jo.getString("Reference");

            HashMap<String,String> users= new HashMap<>();

            users.put("name",name);
            users.put("ref",ref);
            list.add(users);
        }

    } catch (JSONException e) {
        e.printStackTrace();
    }

    ListAdapter adapter = new SimpleAdapter(
            getActivity(), list, R.layout.list_row2,
            new String[]{"name","ref"},
            new int[]{R.id.nom, R.id.email2});

    listView.setAdapter(adapter);
}
private void getJSON() {
    class GetJSON extends AsyncTask<Void, Void, String> {
        ProgressDialog loading;
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            loading = ProgressDialog.show(getActivity(), "Téléchargement", "Veuillez patientez...", false, false);
        }
        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            loading.dismiss();
            JSON_STRING = s;
            getuser();
        }
        @Override
        protected String doInBackground(Void... params) {
            RequestHandler rh = new RequestHandler();
            String s = rh.sendGetRequest(URL);
            return s;
        }
    }
    GetJSON gj = new GetJSON();
    gj.execute();
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    Intent intent = new Intent(getActivity().getApplicationContext(), Viewuser.class);
    HashMap<String, String> map = (HashMap) parent.getItemAtPosition(position);
    String tid = map.get("ref").toString();
    intent.putExtra("ref", tid);
    startActivity(intent);
}

提前致谢

Answer 1

看到这个

Filtering listView data using SimpleAdapter

Answer 2

使adapter成为全局变量将解决您的问题：

更改您的代码：

 public class UsersFragment extends Fragment implements ListView.OnItemClickListener {
 private String JSON_STRING;
 private ImageButton btn1;

 //Make the adapter GLOBAL
 ListAdapter adapter;

 public static final String URL = "http://10.0.3.2/GetPHP/getuser.php";
 public static final String TAG_JSON_ARRAY = "result";
 // List view
 private ListView listView;
 // Search EditText
 EditText inputSearch;

 @Override
 public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
       View rootview = inflater.inflate(R.layout.fragment_users, container, false);
       listView  = (ListView)   rootview.findViewById(R.id.listView);
       inputSearch  = (EditText)   rootview.findViewById(R.id.inputSearch);
       listView.setOnItemClickListener(this);
       btn1=(ImageButton) rootview.findViewById(R.id.btn1);
       inputSearch.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
        // When user changed the Text
        adapter.getFilter().filter(cs);
    }

    @Override
    public void beforeTextChanged(CharSequence arg0, int arg1, int arg2,
                                  int arg3) {
        // TODO Auto-generated method stub

    }

    @Override
    public void afterTextChanged(Editable arg0) {
        // TODO Auto-generated method stub
    }
    });
    getJSON();
    return rootview;
 }

 private void getuser(){
 JSONObject jsonObject = null;
 ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String, String>>();
 try 
 {
    jsonObject = new JSONObject(JSON_STRING);
    JSONArray result = jsonObject.getJSONArray(TAG_JSON_ARRAY);

    for(int i = 0; i<result.length(); i++){
        JSONObject jo = result.getJSONObject(i);
        String name = jo.getString("Nom");
        String ref = jo.getString("Reference");

        HashMap<String,String> users= new HashMap<>();

        users.put("name",name);
        users.put("ref",ref);
        list.add(users);
    }

} catch (JSONException e) {
    e.printStackTrace();
}

adapter = new SimpleAdapter(
        getActivity(), list, R.layout.list_row2,
        new String[]{"name","ref"},
        new int[]{R.id.nom, R.id.email2});

listView.setAdapter(adapter);
}
private void getJSON() {
class GetJSON extends AsyncTask<Void, Void, String> {
    ProgressDialog loading;
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        loading = ProgressDialog.show(getActivity(), "Téléchargement", "Veuillez patientez...", false, false);
    }
    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        loading.dismiss();
        JSON_STRING = s;
        getuser();
    }
    @Override
    protected String doInBackground(Void... params) {
        RequestHandler rh = new RequestHandler();
        String s = rh.sendGetRequest(URL);
        return s;
    }
}
GetJSON gj = new GetJSON();
gj.execute();
}

说明：在您的代码中，您使用的adpater是本地这意味着您不能使用相同的方法在onTextChanged（）中设置过滤器。这就是您无法解析适配器的原因。

如何在列表视图中添加搜索按钮？

2 个答案: