java - 在 arrayadapter 中显示 arraylist 的值以进行自动完成

Question

我有一个适配器，它返回一个包含 2 个字符串的 HashMap 。我希望人们看到的是第一个字符串，当人们单击它时，我想要第二个字符串，但我有点不知道如何做到这一点。

这是我的适配器:

public class PlacesAutoCompleteAdapter extends ArrayAdapter<HashMap<String, String>> implements Filterable {
    private ArrayList<HashMap<String, String>> resultList;

    public PlacesAutoCompleteAdapter(Context context, int textViewResourceId) {
        super(context, textViewResourceId);
    }

    @Override
    public int getCount() {
        return resultList.size();
    }

    @Override
    public HashMap<String, String> getItem(int index) {
        return resultList.get(index);
    }

    @Override
    public Filter getFilter() {
        Filter filter = new Filter() {
            @Override
            protected FilterResults performFiltering(CharSequence constraint) {
                FilterResults filterResults = new FilterResults();
                if (constraint != null) {
                    // Retrieve the autocomplete results.
                    resultList = autocomplete(constraint.toString());

                    // Assign the data to the FilterResults
                    filterResults.values = resultList;
                    filterResults.count = resultList.size();
                }
                return filterResults;
            }

            @Override
            protected void publishResults(CharSequence constraint, FilterResults results) {
                if (results != null && results.count > 0) {
                    notifyDataSetChanged();
                }
                else {
                    notifyDataSetInvalidated();
                }
            }};
        return filter;
    }

    private static final String PLACES_API_BASE = "https://maps.googleapis.com/maps/api/place";
    private static final String TYPE_AUTOCOMPLETE = "/autocomplete";
    private static final String OUT_JSON = "/json";

    private static final String API_KEY = "AIzaSyCpBpPYqky54Ktp4svdxv249xw9wOKQDAU";

    private static final String LOG_TAG = "ExampleApp";



    private ArrayList<HashMap<String, String>> autocomplete(String input) {
        ArrayList<HashMap<String, String>> resultList = null;



        HttpURLConnection conn = null;
        StringBuilder jsonResults = new StringBuilder();
        try {
            StringBuilder sb = new StringBuilder(PLACES_API_BASE + TYPE_AUTOCOMPLETE + OUT_JSON);
            sb.append("?key=" + API_KEY);
            sb.append("&input=" + URLEncoder.encode(input, "utf8"));

            URL url = new URL(sb.toString());
            conn = (HttpURLConnection) url.openConnection();
            InputStreamReader in = new InputStreamReader(conn.getInputStream());

            // Load the results into a StringBuilder
            int read;
            char[] buff = new char[1024];
            while ((read = in.read(buff)) != -1) {
                jsonResults.append(buff, 0, read);
            }
        } catch (MalformedURLException e) {
            Log.e(LOG_TAG, "Error processing Places API URL", e);
            return resultList;
        } catch (IOException e) {
            Log.e(LOG_TAG, "Error connecting to Places API", e);
            return resultList;
        } finally {
            if (conn != null) {
                conn.disconnect();
            }
        }

        try {
            // Create a JSON object hierarchy from the results
            JSONObject jsonObj = new JSONObject(jsonResults.toString());
            JSONArray predsJsonArray = jsonObj.getJSONArray("predictions");

            // Extract the Place descriptions from the results
            resultList = new ArrayList<HashMap<String, String>>(predsJsonArray.length());
            for (int i = 0; i < predsJsonArray.length(); i++) {
                HashMap<String, String> place = new HashMap<String, String>();
                String description = predsJsonArray.getJSONObject(i).getString("description");
                String placeId = predsJsonArray.getJSONObject(i).getString("place_id");
                place.put("description", description);
                place.put("place_id", placeId);
                resultList.add(place);
            }
        } catch (JSONException e) {
            Log.e(LOG_TAG, "Cannot process JSON results", e);
        }

        return resultList;
    }
}

当人们点击它时，我有第二个字符串，所以没关系:

//When click on autocomplete suggestion
        autoCompView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            public void onItemClick(AdapterView<?> listView, View view,
                                    int position, long id) {

                Map<String, String> map = (Map<String, String>) listView.getItemAtPosition(position);

                String location  = map.get("description");
                String reference = map.get("place_id");
                Toast.makeText(getActivity(), location, Toast.LENGTH_SHORT).show();
            }
        });

在我的自动完成 TextView 中，它显示整个 HashMap ，我如何只显示它的第一个字符串，当人们单击它时获取第二个字符串？

提前致谢!

Answer 1

我认为您可以删除 getItem() 并实现 getView()，而不是执行 getItem()

首先，您需要为项目 View 创建一个 XML 文件:

<?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="wrap_content"
              android:orientation="vertical">

    <TextView android:id="@+id/list_item_desc"
              android:textSize="16sp"
              android:textStyle="bold"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:text="Line1"/>

</LinearLayout>

删除getItem()并实现getView()

@Override
    public View getView(int rowIndex, View convertView, ViewGroup parent) {
        View row = convertView;
        if(null == row) {
            LayoutInflater layout = (LayoutInflater)getSystemService(
                    Context.LAYOUT_INFLATER_SERVICE
            );
            row = layout.inflate(R.layout.item_view, null);
        }
        HashMap<String, String> result = resultList.get(rowIndex);
        if(null != result) {
            TextView descTextView = (TextView) row.findViewById(R.id.list_item_desc);
            if(null != desc) {
                descTextView.setText(desc.get("description"));
            }
        }
        return row;
    }

对于您的点击监听器，您只需更改即可

Toast.makeText(getActivity(), location, Toast.LENGTH_SHORT).show();

至

Toast.makeText(getActivity(), reference, Toast.LENGTH_SHORT).show();

您还可以阅读this tutorial关于如何在您的 Android 应用程序中实现地方 API。