我正在通过从Foursquare获取场地并使用Google Map来创建Android地图应用。
我已将MainActivity设置为获取场地结果，MapFragmentClass和VenueModel。
我将Foursquare的所有JSON结果保存到MainActivity中的List venueModelList中。
我想要做的是根据从Foursquare收到的坐标在MapFragmentClass中添加标记。
但是，我试图将venueModelList传递给MapFragmentClass。
感谢任何帮助。感谢。
MainActivity.java
public class MainActivity extends AppCompatActivity implements LocationListener{
private final String VENUE_URL = "https://api.foursquare.com/v2/venues/search?ll=";
private final int LIMIT = 40;
private final double RADIUS = 50000;
private String MOSQUE_URL;
private String RES_URL;
public static final String CLIENT_ID = "";
public static final String CLIENT_SECRET = "";
private static final long MIN_TIME_BW_UPDATES = 20000;
private static final float MIN_DISTANCE_CHANGE_FOR_UPDATES = 1;
private LocationManager locationManager;
private Location lastLocation;
private Location location;
private boolean receivedLocation = false;
private double lt;
private double lg;
private boolean canGetLocation;
private boolean isGPSEnabled;
private boolean isNetworkEnabled;
private boolean updateSettings = false;
private String TAG = "TAG";
private ListView lvVenues;
private Bundle bundle;
private ArrayList<VenueModel> venueModelList;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lvVenues = (ListView) findViewById(R.id.lvVenues);
String t = timeMilisToString(System.currentTimeMillis());
Bundle extras = getIntent().getExtras();
if (extras != null)
{
lt = extras.getDouble("LATITUDE");
lg = extras.getDouble("LONGITUDE");
receivedLocation = true;
}
else
{
receivedLocation = false;
}
location = getLocation();
if (location != null)
{
if(receivedLocation)
{
location.setLatitude(lt);
location.setLongitude(lg);
}
else
{
lt = location.getLatitude();
lg = location.getLongitude();
Log.d("LAT", "Latitude: " + lt);
Log.d("LONG", "Longitude: " + lg);
}
}
double lt = 3.142182;
double lg = 101.710602;
MOSQUE_URL = VENUE_URL + lt + "," + lg
+ "&client_id=" + CLIENT_ID
+ "&client_secret=" + CLIENT_SECRET
+ "&v=" + t
+ "&categoryId=4bf58dd8d48988d138941735"
+ "&radius=" + RADIUS
+ "&limit=" + LIMIT;
RES_URL = VENUE_URL + lt + "," + lg
+ "&client_id=" + CLIENT_ID
+ "&client_secret=" + CLIENT_SECRET
+ "&v=" + t
+ "&categoryId=52e81612bcbc57f1066b79ff"
+ "&radius=" + RADIUS
+ "&limit=" + LIMIT;
}
public class JSONTask extends AsyncTask<String, String, List<VenueModel>>
{
@Override
public List<VenueModel> doInBackground(String... params)
{
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String finalJson = buffer.toString();
JSONObject parentObject = new JSONObject(finalJson);
JSONObject secondObject = parentObject.getJSONObject("response");
JSONArray parentArray = secondObject.getJSONArray("venues");
venueModelList = new ArrayList<>();
for (int i = 0; i < parentArray.length(); i++)
{
JSONObject finalObject = parentArray.getJSONObject(i);
JSONObject thirdObject = finalObject.getJSONObject("location");
try {
VenueModel venueModel = new VenueModel();
venueModel.setId(finalObject.getString("id"));
venueModel.setName(finalObject.getString("name"));
venueModel.setAddress(thirdObject.optString("address"));
venueModel.setPostalCode(thirdObject.optString("postalCode"));
venueModel.setCity(thirdObject.optString("city"));
venueModel.setState(thirdObject.optString("state"));
venueModel.setDistance(thirdObject.getInt("distance"));
venueModel.setLat(thirdObject.getDouble("lat"));
venueModel.setLng(thirdObject.getDouble("lng"));
LatLng coordinate = new LatLng(thirdObject.getDouble("lat"), thirdObject.getDouble("lng"));
venueModel.setCoordinate(coordinate);
venueModelList.add(venueModel);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
Collections.sort(venueModelList);
return venueModelList;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
@Override
protected void onPostExecute(List<VenueModel> result)
{
super.onPostExecute(result);
VenueAdapter adapter = new VenueAdapter(getApplicationContext(), R.layout.row, result);
lvVenues.setAdapter(adapter);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu)
{
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
int id = item.getItemId();
if (id == R.id.action_mosque)
{
new JSONTask().execute(MOSQUE_URL);
FragmentManager fmanager = getSupportFragmentManager();
FragmentTransaction FT = fmanager.beginTransaction();
MapFragmentClass mfc = new MapFragmentClass();
FT.add(R.id.mapLayout, mfc);
FT.commit();
return true;
}
if (id == R.id.action_restaurant)
{
new JSONTask().execute(RES_URL);
FragmentManager fmanager = getSupportFragmentManager();
FragmentTransaction FT = fmanager.beginTransaction();
MapFragmentClass mfc = new MapFragmentClass();
FT.add(R.id.mapLayout, mfc);
FT.commit();
return true;
}
return super.onOptionsItemSelected(item);
}
private String timeMilisToString(long milis)
{
SimpleDateFormat sd = new SimpleDateFormat("yyyyMMdd");
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(milis);
return sd.format(calendar.getTime());
}
public Location getLocation()
{
try
{
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled)
{
Log.v(TAG, "No network provider enabled");
}
else
{
this.canGetLocation = true;
if (isNetworkEnabled)
{
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d(TAG, "Network Enabled");
if(locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}
}
if (isGPSEnabled)
{
if (location == null)
{
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES, MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d(TAG, "GPS Enabled");
if(locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
}
}
}
}
}
catch (Exception e)
{
e.printStackTrace();
}
return location;
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
{
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
@Override
public void onLocationChanged(Location location)
{
lastLocation = location;
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider)
{
Log.v(TAG, "onProviderEnabled");
}
@Override
public void onProviderDisabled(String provider)
{
Log.v(TAG, "onProviderDisabled");
}
public LatLng setCoordinate()
{
LatLng coordinate = new LatLng(getLocation().getLatitude(), getLocation().getLongitude());
LatLng coordinate = new LatLng(lt, lg);
return coordinate;
}
}
VenueModel.java
public class VenueModel implements Comparable<VenueModel>, Parcelable
{
private String id;
private String name;
private String address;
private String postalCode;
private String city;
private String state;
private Integer distance;
private double lat;
private double lng;
private LatLng coordinate;
private List<VenueModel> venueModelList;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public int getDistance() {
return distance;
}
public void setDistance(int distance) {
this.distance = distance;
}
public double getLat() {
return lat;
}
public void setLat(double lat) {
this.lat = lat;
}
public double getLng() {
return lng;
}
public void setLng(double lng) {
this.lng = lng;
}
public String getPostalCode() {
return postalCode;
}
public void setPostalCode(String postalCode) {
this.postalCode = postalCode;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public void setVenueModelList(List<VenueModel> venueModelList)
{
this.venueModelList = venueModelList;
}
public List<VenueModel> getVenueModelList()
{
return venueModelList;
}
public LatLng getCoordinate() {
return coordinate;
}
public void setCoordinate(LatLng coordinate)
{
this.coordinate = coordinate;
}
@Override
public int compareTo(VenueModel venueModel) {
return this.distance.compareTo(venueModel.distance);
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(this.id);
dest.writeString(this.name);
dest.writeString(this.address);
dest.writeString(this.postalCode);
dest.writeString(this.city);
dest.writeString(this.state);
dest.writeValue(this.distance);
dest.writeDouble(this.lat);
dest.writeDouble(this.lng);
dest.writeParcelable(this.coordinate, flags);
dest.writeList(this.venueModelList);
}
public VenueModel() {
}
protected VenueModel(Parcel in) {
this.id = in.readString();
this.name = in.readString();
this.address = in.readString();
this.postalCode = in.readString();
this.city = in.readString();
this.state = in.readString();
this.distance = (Integer) in.readValue(Integer.class.getClassLoader());
this.lat = in.readDouble();
this.lng = in.readDouble();
this.coordinate = in.readParcelable(LatLng.class.getClassLoader());
this.venueModelList = new ArrayList<VenueModel>();
in.readList(this.venueModelList, VenueModel.class.getClassLoader());
}
public static final Parcelable.Creator<VenueModel> CREATOR = new Parcelable.Creator<VenueModel>() {
@Override
public VenueModel createFromParcel(Parcel source) {
return new VenueModel(source);
}
@Override
public VenueModel[] newArray(int size) {
return new VenueModel[size];
}
};
}
MapFragmentClass.java
public class MapFragmentClass extends Fragment implements OnMapReadyCallback
{
private MainActivity mA;
private GoogleMap gmap;
private static final LatLng coordinate = new LatLng(3.152182, 101.710602);
private LatLng coordinate2;
private ArrayList<VenueModel> venueModelList;
@Override
public void onAttach(Context context)
{
super.onAttach(context);
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View v = inflater.inflate(R.layout.activity_maps, container, false);
SupportMapFragment supportMapFragment = (SupportMapFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.map);
supportMapFragment.getMapAsync(this);
return v;
}
@Override
public void onMapReady(GoogleMap googleMap)
{
gmap = googleMap;
gmap.addMarker(new MarkerOptions().position(coordinate).title("Your location").draggable(true));
gmap.moveCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 14));
}
}
答案 0 :(得分：1)
使用GSON将该对象转换为JSON字符串，然后再将该字符串重新转换为列表对象。
MapFragment.getInstance(new Gson().toJson(venuList));
public static final getInstance(String venusStringListObj) {}
Bundle argument = new Bundle();
argument.putString("VENUES", venusStringListObj);
MapFragment fragment = new MapFragment();
fragment.setArgument(argument);
return fragment;
}
onCreate(...) {
private List<VenueModel> venueList;
Type listType = new TypeToken<ArrayList<VenueModel>>() {}.getType();
String venueStringRecvFromFragArg = getArguments().getString("VENUES");
venueList = new Gson().fromJson(venueStringRecvFromFragArg, listType);
}
答案 1 :(得分：0)
MapFragmentClass mfc = new MapFragmentClass();
Bundle b = new Bundle();
b.putParcelableArrayList("Parcel", list);
mfc.setArguments(b);
FT.add(R.id.mapLayout, mfc);
FT.commit();
要在MapFragment中访问arrayList，请使用此
ArrayList<VenueModel> myList = getArguments().getParcelableArrayList("Parcel");