我遇到geocoder.ispresent()始终返回false的问题。我用谷歌搜索解决方案，发现谷歌地图服务没有启用。我们如何才能启用该服务？谁能指导我？
package com.incv.mobile.freejscf;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import android.app.Application;
import android.content.Context;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
public class MyApplication extends Application implements LocationListener {
double latitude = 0;
double longitude = 0;
@Override
public void onCreate() {
super.onCreate();
Location mLocation = null;
if (Geocoder.isPresent()) {
(new GetAddressTask(this)).execute(mLocation);
}
else{
Log.e("Not", "Geocoder is not present");
}
}
private class GetAddressTask extends
AsyncTask<Location, Void, String> {
Context mContext;
public GetAddressTask(Context context) {
super();
mContext = context;
}
/**
* Get a Geocoder instance, get the latitude and longitude
* look up the address, and return it
*
* @params params One or more Location objects
* @return A string containing the address of the current
* location, or an empty string if no address can be found,
* or an error message
*/
@Override
protected String doInBackground(Location... params) {
Geocoder geocoder =
new Geocoder(mContext, Locale.getDefault());
// Get the current location from the input parameter list
Location loc = params[0];
// Create a list to contain the result address
List<Address> addresses = null;
try {
/*
* Return 1 address.
*/
addresses = geocoder.getFromLocation(loc.getLatitude(),
loc.getLongitude(), 1);
} catch (IOException e1) {
Log.e("LocationSampleActivity",
"IO Exception in getFromLocation()");
e1.printStackTrace();
return ("IO Exception trying to get address");
} catch (IllegalArgumentException e2) {
// Error message to post in the log
String errorString = "Illegal arguments " +
Double.toString(loc.getLatitude()) +
" , " +
Double.toString(loc.getLongitude()) +
" passed to address service";
Log.e("LocationSampleActivity", errorString);
e2.printStackTrace();
return errorString;
}
// If the reverse geocode returned an address
if (addresses != null && addresses.size() > 0) {
// Get the first address
Address address = addresses.get(0);
/*
* Format the first line of address (if available),
* city, and country name.
*/
String addressText = String.format(
"%s, %s, %s",
// If there's a street address, add it
address.getMaxAddressLineIndex() > 0 ?
address.getAddressLine(0) : "",
// Locality is usually a city
address.getLocality(),
// The country of the address
address.getCountryName());
// Return the text
return addressText;
} else {
return "No address found";
}
}
protected void onPostExecute(String address) {
// mAddress.setText(address);
Log.e("Address", address.toString());
}
}
public void getAddress(View v) {
// Ensure that a Geocoder services is available
}
@Override
public void onLocationChanged(Location arg0) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
在上面的代码中首先onCreate methid得到执行。但它总是进入其他部分。这意味着GeoCoder.isProvider（）返回false。
答案 0 :(得分：0)
只需按照开发人员指南在Android应用中设置地图即可。 以下是快速指南