【发布时间】：2015-12-13 01:35:40
【问题描述】：
我的应用程序有一个自动完成适配器，我正在从 Google Places API 获取 json 结果。我的麻烦是试图让结果显示在屏幕上。我正在使用本指南：http://examples.javacodegeeks.com/android/android-google-places-autocomplete-api-example/
在大多数情况下，代码看起来不错，但无论出于何种原因，我都无法将任何内容打印到我的显示器上。我不太了解过滤器的工作原理，也许解释一下它如何与自动完成适配器一起工作会有所帮助。
我的 onCreate 是：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
buildGoogleApiClient();
setContentView(R.layout.activity_maps);
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
if (savedInstanceState != null) {
mIsResolving = savedInstanceState.getBoolean(KEY_IS_RESOLVING);
mShouldResolve = savedInstanceState.getBoolean(KEY_SHOULD_RESOLVE);
}
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)
.setInterval(10 * 1000) //10 seconds, in milliseconds
.setFastestInterval(1 * 1000); //1 second, in milliseconds
Log.d(TAG, "GoogleApiClient built");
if (savedInstanceState != null) {
mSignInProgress = savedInstanceState
.getInt(SAVED_PROGRESS, STATE_DEFAULT);
}
mShouldResolve = true;
mGoogleApiClient.connect();
Log.d(TAG, "Starting sign-in");
AutoCompleteTextView autoCompView = (AutoCompleteTextView)
findViewById(R.id.autoCompleteTextView);
autoCompView.setAdapter(new GooglePlacesAutocompleteAdapter(this, R.layout.activity_maps));
autoCompView.setOnItemClickListener(this);
}
我获取Json结果的方法是：
public ArrayList<String> autocomplete(String input) {
Log.d(TAG, "performSearch()");
ArrayList resultList = null;
AsyncTask<ArrayList<String>, Void, ArrayList>
myTask = new AsyncTask<ArrayList<String>, Void, ArrayList>() {
AutoCompleteTextView text = (AutoCompleteTextView)
findViewById(R.id.autoCompleteTextView);
private String input = text.getText().toString();
@Override
protected ArrayList doInBackground(ArrayList<String>... params) {
Log.d(TAG, "Starting Search");
ArrayList resultList = null;
HttpURLConnection conn = null;
StringBuilder jsonResults = new StringBuilder();
try {
KEYWORD = input;
ENDPOINT = Uri
.parse("https://maps.googleapis.com/maps/api/place/nearbysearch/json")
.buildUpon()
.appendQueryParameter("location", LOCATION)
.appendQueryParameter("radius", "10000")
.appendQueryParameter("keyword", KEYWORD)
.appendQueryParameter("key", API_KEY)
.build();
URL url = new URL(ENDPOINT.toString());
Log.d(TAG, "URL: " + url);
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);
}
Log.d(TAG, jsonResults.toString());
} catch (MalformedURLException e) {
Log.e(TAG, "Error processing Places API URL", e);
return resultList;
} catch (IOException e) {
Log.e(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("results");
// Extract the Place descriptions from the results
resultList = new ArrayList(predsJsonArray.length());
for (int i = 0; i < predsJsonArray.length(); i++) {
System.out.println(predsJsonArray.getJSONObject(i).getString("name"));
System.out.println(predsJsonArray.getJSONObject(i).getString("vicinity"));
System.out.println("=====================================================");
resultList.add(predsJsonArray.getJSONObject(i).getString("name"));
resultList.add(predsJsonArray.getJSONObject(i).getString("vicinity"));
}
} catch (JSONException e) {
Log.e(TAG, "Cannot process JSON results", e);
}
Log.d(TAG, resultList.toString());
return resultList;
}
};
myTask.execute();
Log.d(TAG, resultList.toString());
return resultList;
}
我的过滤器类是：
class GooglePlacesAutocompleteAdapter extends ArrayAdapter implements Filterable {
private ArrayList resultList;
public GooglePlacesAutocompleteAdapter(Context context, int textViewResourceId) {
super(context, textViewResourceId);
}
@Override
public int getCount() {
return resultList.size();
}
@Override
public String getItem(int index) {
return (String) 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, Filter.FilterResults results) {
if (results != null && results.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
}
};
return filter;
}
}
我知道我从 google 得到了一个合理的结果，我构建的数组看起来像这样（它包括名称和附近）：
[Midtown Global Market, 920 East Lake Street #G10, Minneapolis, The Anchor Fish & Chips, 302 13th Avenue Northeast, Minneapolis, Brasa Premium Rotisserie, 600 East Hennepin Avenue, Minneapolis, Wedge 社区合作社，2105 Lyndale Avenue South，明尼阿波利斯，陶自然 食品，2200 Hennepin Avenue，明尼阿波利斯，新鲜天然食品，1075 Highway 96 West, Saint Paul, Whole Foods Market, 222 Hennepin Avenue, 明尼阿波利斯, Sen Yai Sen Lek Thai, 2422 Central Avenue Northeast, 明尼阿波利斯，密西西比市场天然食品合作社，塞尔比大道 622 号， 圣保罗，东区食品合作社，2551 Central Avenue Northeast， 明尼阿波利斯，Bills Imported Foods，721 West Lake Street，Minneapolis， Seoul Foods, 1071 East Moore Lake Drive, Minneapolis, Seward Community Co-op - Franklin Store, 2823 East Franklin Avenue, Minneapolis, Foxy Falafel, 791 Raymond Avenue, Saint Paul, Asian Foods, 1300 L'Orient Street, Saint Paul, Pohl Distributing Co, 510 Kasota Avenue Southeast, 明尼阿波利斯，彩虹食品，1566 University Avenue West，圣保罗， 蒲公英厨房卡车，800 Nicollet Mall，明尼阿波利斯，世界街 厨房，2743 Lyndale Avenue South #5，Minneapolis，CES Food Shelf， 明尼阿波利斯东 19 街]
感谢任何帮助，谢谢！
[编辑] 这是我的 activity_maps 的 XML：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.hudsoncorp.zahudson.roadtrip.MapsActivity">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/map"
tools:context="com.hudsoncorp.zahudson.roadtrip.MapsActivity"
android:name="com.google.android.gms.maps.SupportMapFragment"/>
<RelativeLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp">
<AutoCompleteTextView
android:id="@+id/autoCompleteTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dp"
android:hint="Search location"
android:background="#FFFFFF"
android:textColor="#00000F"
android:theme="@android:style/Widget.Material.AutoCompleteTextView"
android:ems="10"
android:shadowColor="@color/background_floating_material_dark">
<requestFocus />
</AutoCompleteTextView>
</RelativeLayout>
</RelativeLayout>
【问题讨论】：
标签： java android json google-places-api autocompletetextview