无法使用Marker类的getPosition（）方法访问当前标记位置。
代码：
package com.example.deepak.vibring;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.ContentValues;
import android.content.Context;
import android.content.DialogInterface;
import android.database.sqlite.SQLiteDatabase;
import android.location.Address;
import android.location.Criteria;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import java.io.IOException;
import java.util.List;
/**
* Created by deepak on 8/2/2015.
*/
public class AddNewLocationActivity extends Activity {
GoogleMap googleMap;
EditText edtLocation;
Marker marker;
List<Address> addressList;
VibRIngDatabase vibRIngDatabase;
double latitude, longitude;
Geocoder geocoder;
LatLng latLng;
String locationAddress;
AlertDialog.Builder dialogBuilder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_addnewlocation);
createMapView();// Rendering the Google Map in the fragment
addMarkerAtCurrent(); // Adding marker at the current location of the device
mapClick(); // On clicking the map
vibRIngDatabase = new VibRIngDatabase(this);
}
//Display the Google Map inside the fragment
private void createMapView() {
/**
* Catch the null pointer exception that
* may be thrown when initialising the map
*/
try {
if (googleMap == null) {
googleMap = ((MapFragment) getFragmentManager().findFragmentById(
R.id.map)).getMap();
googleMap.setMyLocationEnabled(true); //To See my current location
/**
* If the map is still null after attempted initialisation,
* show an error to the user
*/
if (googleMap == null) {
Toast.makeText(getApplicationContext(),
"Error creating map", Toast.LENGTH_SHORT).show();
}
}
} catch (NullPointerException exception) {
Log.e("mapApp", exception.toString());
}
}
// Adding marker to the current location
public void addMarkerAtCurrent() {
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
// Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
// Get Current Location
Location myLocation = locationManager.getLastKnownLocation(provider);
// set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
// Get latitude of the current location
latitude = myLocation.getLatitude();
// Get longitude of the current location
longitude = myLocation.getLongitude();
// Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
String address = getLocationAddress(latitude, longitude);
googleMap.addMarker(
new MarkerOptions()
.position(new LatLng(latitude, longitude))
.title(address));
// Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(14));
}
public LatLng search(View v) {
//Toast.makeText(this,"Button clicked",Toast.LENGTH_LONG).show();
edtLocation = (EditText) findViewById(R.id.edtLocation);
String location = edtLocation.getText().toString();
// Toast.makeText(this, "Location " + location, Toast.LENGTH_LONG).show();
if (location != null) {
//Geocoder class is used to used to get Latitude and Longitude from location name & vice versa
// Toast.makeText(this,"If block entered",Toast.LENGTH_LONG).show();
Geocoder geocoder = new Geocoder(this);
try {
addressList = geocoder.getFromLocationName(location, 1);
} catch (IOException e) {
e.printStackTrace();
}
// To get address from list<Address>
Address address = addressList.get(0);
//String featureName = address.getFeatureName();
String addresssLine = address.getAddressLine(0);
String locality = address.getLocality();
// String subLocality = address.getSubLocality();
String adminArea = address.getAdminArea();
String locationAddress = addresssLine + " " + locality + " " + adminArea;
Toast.makeText(getApplicationContext(), "Address " + locationAddress, Toast.LENGTH_LONG).show();
//To get Latitude & Longitude
LatLng latLng = new LatLng(address.getLatitude(), address.getLongitude());
googleMap.clear();
//Adding marker to the specified location
googleMap.addMarker(new MarkerOptions().position(latLng).title(locationAddress));
// Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(14));
}
return latLng;
}
/*public void saveLocation(View v) {
Toast.makeText(getApplicationContext(), "saveLocation called", Toast.LENGTH_LONG).show();
edtLocation = (EditText) findViewById(R.id.edtLocation);
String location_name = edtLocation.getText().toString();
Toast.makeText(getApplicationContext(), location_name, Toast.LENGTH_LONG).show();
SQLiteDatabase db = vibRIngDatabase.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(VibRIngDatabase.LOCATION_NAME, location_name);
long id = db.insert(VibRIngDatabase.TABLE_NAME, VibRIngDatabase.LOCATION_NAME, cv);
Toast.makeText(getApplicationContext(), "id = " + id, Toast.LENGTH_LONG).show();
if (id < 0)
Toast.makeText(getApplicationContext(), "Insertion Unsuccessful", Toast.LENGTH_LONG).show();
else
Toast.makeText(getApplicationContext(), "Insertion Successful", Toast.LENGTH_LONG).show();
}*/
// Clicking the GoogleMap
public LatLng mapClick() {
googleMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng arg) {
//Toast.makeText(getApplicationContext(), "Map Clicked", Toast.LENGTH_SHORT).show();
// Getting the Latitude & Longitude of previously touched location
latLng = arg;
//Clear the previously touched position
googleMap.clear();
latitude = latLng.latitude;
//Toast.makeText(getApplicationContext(),"Latitude = " +longitude,Toast.LENGTH_SHORT).show();
longitude = latLng.longitude;
//Toast.makeText(getApplicationContext(),"Longitude = " +longitude,Toast.LENGTH_SHORT).show();
String name = getLocationAddress(latitude, longitude);
//Placing the marker on the touched position
googleMap.addMarker(new MarkerOptions().position(latLng).title(locationAddress));
// Moving camera to the touched position
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Animating to touched position
// googleMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
}
});
return latLng;
}
public String getLocationAddress(double latitude, double longitude) {
this.latitude = latitude;
this.longitude = longitude;
geocoder = new Geocoder(getApplicationContext());
try {
addressList = geocoder.getFromLocation(latitude, longitude, 1);
} catch (IOException e) {
e.printStackTrace();
}
Address address = addressList.get(0);
String addressLine = address.getAddressLine(0);
//String featureName = address.getFeatureName();
String locality = address.getLocality();
String adminArea = address.getAdminArea();
locationAddress = addressLine + " " + locality + " " + adminArea;
return locationAddress;
}
// On clicking add button openDialog method will be called
public void openDialog(View v) {
Toast.makeText(getApplicationContext(), "eeeeeeeeeeeeeeeeeeeeee", Toast.LENGTH_LONG).show();
dialogBuilder = new AlertDialog.Builder(this);
LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.custom_dialog, null, false);
dialogBuilder.setTitle("Set Mode");
dialogBuilder.setView(view);
AlertDialog dialog = dialogBuilder.create();
dialog.show();
//dialog.getWindow().setLayout(600, 800);
TextView lat = (TextView) view.findViewById(R.id.lblLatitude);
TextView longi = (TextView) view.findViewById(R.id.lblLongitude);
TextView location_name = (TextView) view.findViewById(R.id.lblLocationName);
//To retrieve the current position of the marker
latLng = marker.getPosition();
double lati1 = latLng.latitude;
double longi1 = latLng.longitude;
String name = getLocationAddress(lati1, longi1);
Toast.makeText(getApplicationContext(), "name " + name, Toast.LENGTH_LONG).show();
lat.setText(Double.toString(lati1));
longi.setText(Double.toString(longi1));
location_name.setText(name);
RadioGroup rg = (RadioGroup) view.findViewById(R.id.modesRadioGroup);
rg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
public void onCheckedChanged(RadioGroup group, int checkedId) {
switch (checkedId) {
case R.id.vibrationRadioButton:
Toast.makeText(getApplicationContext(), "Vibration clicked", Toast.LENGTH_LONG).show();
break;
case R.id.muteRadioButton:
Toast.makeText(getApplicationContext(), "Mute clicked", Toast.LENGTH_LONG).show();
break;
case R.id.ringingRadioButton:
Toast.makeText(getApplicationContext(), "Ringing clicked", Toast.LENGTH_LONG).show();
break;
default:
break;
}
}
});
}
}
在此代码中，我使用的是Google Map。我的活动中有一个名为ADD的按钮。 单击ADD，调用openDialog（）方法，该方法负责创建自定义对话框。这里的一切都运行正常，除了代码将给我标记的位置。单击地图后或搜索EditText后。我正在尝试使用Marker类的getPosition（）方法访问当前标记位置，但它无法正常工作。
请检查openDialog（）方法。
答案 0 :(得分：0)
您的marker变量始终为空。您永远不会将值赋给此变量。
我不了解您应用的完整逻辑，但看起来您应该在尝试添加新标记后为marker字段指定值。例如，对于search方法，您应该更改以下行：
googleMap.addMarker(new MarkerOptions().position(latLng).title(locationAddress));
到
marker=googleMap.addMarker(new MarkerOptions().position(latLng).title(locationAddress));
其他方法相同。 在尝试使用之前，您应该将值指定给标记。