我正在做一个使用GPS检索用户位置然后将其重定向到新意图的应用程序，假设用户处于“曲线”状态，它会将用户重定向到Curve.class，但我得到了这个错误，它一直阻止我继续前进。
01-15 17:21:09.644: D/HttpRetriever(309): <?xml version="1.0" encoding="UTF-8" standalone="yes"?><ResultSet xmlns:ns1="http://www.yahooapis.com/v1/base.rng" version="2.0" xml:lang="en-US"><Error>0</Error><ErrorMessage>No error</ErrorMessage><Locale>en-US</Locale><Found>1</Found><Quality>99</Quality><Result><quality>72</quality><latitude>3.158695</latitude><longitude>101.611586</longitude><offsetlat>3.158695</offsetlat><offsetlon>101.611586</offsetlon><radius>400</radius><name>3.1580999999999997, 101.61209833333332</name><line1>Jalan Pju 7/3</line1><line2>47800 Bandar Utama</line2><line3></line3><line4>Malaysia</line4><house></house><street>Jalan Pju 7/3</street><xstreet></xstreet><unittype></unittype><unit></unit><postal>47800</postal><neighborhood>Bandar Utama</neighborhood><city>Sungai Buloh</city><county>Petaling</county><state>Selangor</state><country>Malaysia</country><countrycode>MY</countrycode><statecode></statecode><countycode></countycode><uzip>47800</uzip><hash></hash><woeid>28347311</woeid><woetype>11</woetype></Result></ResultSet>
01-15 17:21:09.644: D/HttpRetriever(309): <!-- nws01.maps.bf1.yahoo.com uncompressed/chunked Tue Jan 15 09:21:01 PST 2013 -->
01-15 17:21:09.644: D/HttpRetriever(309): <!-- wws07.geotech.ne1.yahoo.com uncompressed/chunked Tue Jan 15 09:21:00 PST 2013 -->
01-15 17:21:09.733: D/dalvikvm(309): GC_FOR_MALLOC freed 2299 objects / 157648 bytes in 58ms
01-15 17:21:09.754: D/XmlParser(309): Location:-Jalan Pju 7/3-47800 Bandar Utama-Malaysia
01-15 17:21:10.134: D/AndroidRuntime(309): Shutting down VM
01-15 17:21:10.134: W/dalvikvm(309): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
01-15 17:21:10.157: E/AndroidRuntime(309): FATAL EXCEPTION: main
01-15 17:21:10.157: E/AndroidRuntime(309): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.javacodegeeks.android.lbs/com.javacodegeeks.android.lbs.Curve}: java.lang.NullPointerException
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.os.Handler.dispatchMessage(Handler.java:99)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.os.Looper.loop(Looper.java:123)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread.main(ActivityThread.java:4627)
01-15 17:21:10.157: E/AndroidRuntime(309): at java.lang.reflect.Method.invokeNative(Native Method)
01-15 17:21:10.157: E/AndroidRuntime(309): at java.lang.reflect.Method.invoke(Method.java:521)
01-15 17:21:10.157: E/AndroidRuntime(309): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
01-15 17:21:10.157: E/AndroidRuntime(309): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
01-15 17:21:10.157: E/AndroidRuntime(309): at dalvik.system.NativeStart.main(Native Method)
01-15 17:21:10.157: E/AndroidRuntime(309): Caused by: java.lang.NullPointerException
01-15 17:21:10.157: E/AndroidRuntime(309): at com.javacodegeeks.android.lbs.Curve.onCreate(Curve.java:59)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-15 17:21:10.157: E/AndroidRuntime(309): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
01-15 17:21:10.157: E/AndroidRuntime(309): ... 11 more
01-15 17:21:11.204: D/All Products:(309): {"success":1,"daftar_promotion":[{"id":"26","PromoImage":"\/images\/ego1.jpg","PromoCate":"Health ","PromoDesc":"5% discount for items above RM200","PromoDateStart":"1-1-2013","Contact":"","PromoDateEnd":"31-1-2013","PromoName":"Egonutritions 5% "},{"id":"27","PromoImage":"\/images\/dna.png","PromoCate":"Fashion","PromoDesc":"20% off for all shoes","PromoDateStart":"1-1-2013","Contact":"","PromoDateEnd":"31-1-2013","PromoName":"DNA New Year Sales"}]}
01-15 17:21:11.204: W/System.err(309): org.json.JSONException: No value for PromoID
01-15 17:21:11.404: W/System.err(309): at org.json.JSONObject.get(JSONObject.java:354)
01-15 17:21:11.484: W/System.err(309): at org.json.JSONObject.getString(JSONObject.java:510)
01-15 17:21:11.484: W/System.err(309): at com.javacodegeeks.android.lbs.Curve$Activity.doInBackground(Curve.java:105)
01-15 17:21:11.484: W/System.err(309): at com.javacodegeeks.android.lbs.Curve$Activity.doInBackground(Curve.java:1)
01-15 17:21:11.484: W/System.err(309): at android.os.AsyncTask$2.call(AsyncTask.java:185)
01-15 17:21:11.484: W/System.err(309): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
01-15 17:21:11.484: W/System.err(309): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
01-15 17:21:11.484: W/System.err(309): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
01-15 17:21:11.484: W/System.err(309): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
01-15 17:21:11.534: W/System.err(309): at java.lang.Thread.run(Thread.java:1096)
这是我的Curve.java
package com.javacodegeeks.android.lbs;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.widget.Toast;
import lbs.promotion.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.AdapterView.OnItemClickListener;
public class Curve extends Activity {
private ProgressDialog pDialog;
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> DaftarPromotion = new ArrayList<HashMap<String, String>>();
private static String url_daftar_promotion = "http://10.0.2.2/webserver_maaug/promotion/daftar_promotion.php";
public static final String TAG_SUCCESS = "success";
public static final String TAG_DAFTAR_PROMOTION = "daftar_promotion";
public static final String TAG_ID_PROMO = "PromoID";
public static final String TAG_NAMA_PROMO = "PromoName";
public static final String TAG_LINK_IMAGE_PROMO = "PromoImage";
public static final String TAG_DESC_PROMO= "PromoDesc";
public static final String TAG_CATE_PROMO = "PromoCate";
JSONArray daftar_promotion = null;
ListView list;
PromotionListAdapter adapter;
private Curve activity;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DaftarPromotion = new ArrayList<HashMap<String, String>>();
new Activity().execute();
activity = this;
list = (ListView) findViewById(R.id.list);
list.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
}
});
}
public void SetListViewAdapter(ArrayList<HashMap<String, String>> daftar) {
adapter = new PromotionListAdapter(activity, daftar);
list.setAdapter(adapter);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == 100) {
Intent intent = getIntent();
finish();
startActivity(intent);
}
}
class Activity extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(Curve.this);
pDialog.setMessage("Please Wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
List<NameValuePair> params = new ArrayList<NameValuePair>();
JSONObject json = jParser.makeHttpRequest(url_daftar_promotion, "GET",params);
Log.d("All Products: ", json.toString());
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
daftar_promotion = json.getJSONArray(TAG_DAFTAR_PROMOTION);
for (int i = 0; i < daftar_promotion.length();i++){
JSONObject c = daftar_promotion.getJSONObject(i);
String PromoID = c.getString(TAG_ID_PROMO);
String PromoName = c.getString(TAG_NAMA_PROMO);
String PromoImage = c.getString(TAG_LINK_IMAGE_PROMO);
String PromoDesc = c.getString(TAG_DESC_PROMO);
String PromoCate = c.getString(TAG_CATE_PROMO);
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_ID_PROMO, PromoID);
map.put(TAG_NAMA_PROMO, PromoName);
map.put(TAG_LINK_IMAGE_PROMO, PromoImage);
map.put(TAG_DESC_PROMO, PromoDesc);
map.put(TAG_CATE_PROMO, PromoCate);
DaftarPromotion.add(map);
}
} else {
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
pDialog.dismiss();
runOnUiThread(new Runnable() {
public void run() {
SetListViewAdapter(DaftarPromotion);
}
});
}
}
}
这是将用户重定向到曲线意图的主要活动
package com.javacodegeeks.android.lbs;
import java.text.DecimalFormat;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
import com.javacodegeeks.android.lbs.model.GeoCodeResult;
import com.javacodegeeks.android.lbs.services.GeoCoder;
public class LbsGeocodingActivity extends Activity {
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES = 1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 1000; // in Milliseconds
private GeoCoder geoCoder = new GeoCoder();
double longi = 0.0;
double lati = 0.0;
String lon = "";
String lat = "";
protected LocationManager locationManager;
protected Location currentLocation;
protected Button retrieveLocationButton;
protected Button reverseGeocodingButton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
retrieveLocationButton = (Button) findViewById(R.id.retrieve_location_button);
reverseGeocodingButton = (Button) findViewById(R.id.reverse_geocoding_button);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MINIMUM_TIME_BETWEEN_UPDATES,
MINIMUM_DISTANCE_CHANGE_FOR_UPDATES,
new MyLocationListener()
);
retrieveLocationButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
getLocation();
}
});
reverseGeocodingButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
performReverseGeocodingInBackground();
}
});
}
protected void performReverseGeocodingInBackground() {
getLocation();
new ReverseGeocodeLookupTask().execute((Void[])null);
}
protected void getLocation() {
currentLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
// if (currentLocation != null) {
// String message = String.format(
// "ori" "Current Location \n Longitude: %1$s \n Latitude: %2$s",
// currentLocation.getLongitude(), currentLocation.getLatitude()
// );
// Toast.makeText(LbsGeocodingActivity.this, message,
// Toast.LENGTH_LONG).show();
// }
}
private class MyLocationListener implements LocationListener {
public void onLocationChanged(Location location) {
String message = String.format(
"New Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
// Toast.makeText(LbsGeocodingActivity.this, message, Toast.LENGTH_LONG).show();
}
public void onStatusChanged(String s, int i, Bundle b) {
// Toast.makeText(LbsGeocodingActivity.this, "Provider status changed",
//Toast.LENGTH_LONG).show();
}
public void onProviderDisabled(String s) {
// Toast.makeText(LbsGeocodingActivity.this,
// "Provider disabled by the user. GPS turned off",
// Toast.LENGTH_LONG).show();
}
public void onProviderEnabled(String s) {
//Toast.makeText(LbsGeocodingActivity.this,
// "Provider enabled by the user. GPS turned on",
// Toast.LENGTH_LONG).show();
}
}
public class ReverseGeocodeLookupTask extends AsyncTask <Void, Void, GeoCodeResult> {
private ProgressDialog progressDialog;
@Override
protected void onPreExecute() {
this.progressDialog = ProgressDialog.show(
LbsGeocodingActivity.this,
"Please wait", // title
"Acquiring Location", // message
true // indeterminate
);
}
@Override
protected GeoCodeResult doInBackground(Void... params) {
return geoCoder.reverseGeoCode(currentLocation.getLatitude(), currentLocation.getLongitude());
}
@Override
protected void onPostExecute(GeoCodeResult result) {
this.progressDialog.cancel();
//Toast.makeText(LbsGeocodingActivity.this, result.toString(), Toast.LENGTH_LONG).show();
DecimalFormat format = new DecimalFormat();
format.setMaximumFractionDigits(4);
longi = currentLocation.getLongitude();
lati = currentLocation.getLatitude();
String lon = format.format(longi);
String lat = format.format(lati);
if((lon.equalsIgnoreCase("101.6121")) && (lat.equalsIgnoreCase("3.1581")) ){
//Toast.makeText(LbsGeocodingActivity.this, "The curve", Toast.LENGTH_LONG).show();
Intent intent = new Intent(LbsGeocodingActivity.this, Curve.class);
intent.putExtra("lon",lon);
intent.putExtra("lat",lat);
startActivity(intent);
}
else if((lon.equalsIgnoreCase("101.5178")) && (lat.equalsIgnoreCase("3.0724")) ){
//Toast.makeText(LbsGeocodingActivity.this, "Sacc", Toast.LENGTH_LONG).show();
Intent intent = new Intent(LbsGeocodingActivity.this, Sacc.class);
intent.putExtra("lon",lon);
intent.putExtra("lat",lat);
startActivity(intent);
}
else if((lon.equalsIgnoreCase("101.6356")) && (lat.equalsIgnoreCase("3.1175")) ){
//Toast.makeText(LbsGeocodingActivity.this, "Jaya One", Toast.LENGTH_LONG).show();
Intent intent = new Intent(LbsGeocodingActivity.this, Jaya.class);
intent.putExtra("lon",lon);
intent.putExtra("lat",lat);
startActivity(intent);
}
}
}
}
答案 0 :(得分：1)
在日志中：
org.json.JSONException：PromoID没有值
表示jsonObject不包含名称为PromoID的任何键。将您的PromoID改为id
public static final String TAG_ID_PROMO = "id";
答案 1 :(得分：0)
我怀疑是那个
list = (ListView) findViewById(R.id.list);
list.setOnItemClickListener(new OnItemClickListener() {
会有麻烦。它是否存在于layout.xml中？如果你说的话会更容易，哪一行是Curve.java:59