Java 尝试访问当前位置时出现错误和应用程序崩溃
错误： E/AndroidRuntime:致命异常：主 进程：com.uws.pnai.mapsapi，PID:15830 java.lang.NullPointerException：尝试对空对象引用调用虚拟方法“double android.location.location.getLatitude” 在com.uws.pnai.mapsapi.MapActivity$1.onCompleteMapActivity.java:77 位于com.google.android.gms.tasks.zzf.run未知源 位于android.os.Handler.handleCallbackHandler.java:751 在android.os.Handler.dispatchMessageHandler.java:95 在android.os.Looper.Looper.java:154 在android.app.ActivityThread.mainActivityThread.java:6780 在java.lang.reflect.Method.Invokenactive方法中 在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.runZygoteInit.java:1500Java 尝试访问当前位置时出现错误和应用程序崩溃,java,android,google-maps-api-3,Java,Android,Google Maps Api 3,错误： E/AndroidRuntime:致命异常：主 进程：com.uws.pnai.mapsapi，PID:15830 java.lang.NullPointerException：尝试对空对象引用调用虚拟方法“double android.location.location.getLatitude” 在com.uws.pnai.mapsapi.MapActivity$1.onCompleteMapActivity.java:77 位于com.google.android.gms.tasks
在com.android.internal.os.ZygoteInit.mainZygoteInit.java:1390中，首先在build.gradle文件中添加此实现 在该实现之后，在活动或片段中实现LocationListener，然后实现其功能，然后 在onCreate getLocation中调用此方法； 然后在这个函数中添加这些行
compile 'com.google.android.gms:play-services-location:11.2.0'
protected void getLocation() {
if (isLocationEnabled(MainActivity.this)) {
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
criteria = new Criteria();
bestProvider = String.valueOf(locationManager.getBestProvider(criteria, true)).toString();
//You can still do this if you like, you might get lucky:
Location location = locationManager.getLastKnownLocation(bestProvider);
if (location != null) {
Log.e("TAG", "GPS is on");
latitude = location.getLatitude();
longitude = location.getLongitude();
Toast.makeText(MainActivity.this, "latitude:" + latitude + " longitude:" + longitude, Toast.LENGTH_SHORT).show();
searchNearestPlace(voice2text);
}
else{
//This is what you need:
locationManager.requestLocationUpdates(bestProvider, 1000, 0, this);
}
}
else
{
//prompt user to enable location....
//.................
}
}
干杯快乐编码如果您想要持续的位置更新，您可以使用后台服务。下面的代码用于位置服务
@Override
public void onLocationChanged(Location location) {
//Hey, a non null location! Sweet!
//remove location callback:
locationManager.removeUpdates(this);
//open the map:
latitude = location.getLatitude();
longitude = location.getLongitude();
Toast.makeText(MainActivity.this, "latitude:" + latitude + " longitude:" + longitude, Toast.LENGTH_SHORT).show();
searchNearestPlace(voice2text);
}
public class LocationTracking extends Service {
private static final String TAG = "BOOMBOOMTESTGPS";
private LocationManager mLocationManager = null;
private static final int LOCATION_INTERVAL = 10000;
private static final float LOCATION_DISTANCE = 0;
double latitude; // latitude
double longitude; // longitude
String emp_id=Login.strUserID;;
View view;
private class LocationListener implements android.location.LocationListener
{
Location mLastLocation;
public LocationListener(String provider)
{
Log.e(TAG, "LocationListener " + provider);
mLastLocation = new Location(provider);
}
@Override
public void onLocationChanged(Location location)
{
ConnectivityManager cn = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo nf = cn.getActiveNetworkInfo();
if (nf != null && nf.isConnected() == true) {
Log.e(TAG, "onLocationChanged: " + location);
latitude=location.getLatitude();
longitude=location.getLongitude();
SendQueryString(latitude,longitude);
Log.d("tag","lat"+latitude+"Long"+longitude+"");
Toast.makeText(LocationTracking.this,"Lat and Long"+location+"emp_id"+emp_id+"",Toast.LENGTH_LONG).show();
mLastLocation.set(location);
}else{
Toast.makeText(LocationTracking.this,"Bad network",Toast.LENGTH_LONG).show();
showErrorToast(view);
}
}
public void showErrorToast(View view) {
MDToast.makeText(LocationTracking.this, "Bad Network Connection", MDToast.LENGTH_LONG, MDToast.TYPE_ERROR);
}
@Override
public void onProviderDisabled(String provider)
{
Log.e(TAG, "onProviderDisabled: " + provider);
}
@Override
public void onProviderEnabled(String provider)
{
Log.e(TAG, "onProviderEnabled: " + provider);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
Log.e(TAG, "onStatusChanged: " + provider);
}
}
LocationListener[] mLocationListeners = new LocationListener[] {
new LocationListener(LocationManager.GPS_PROVIDER),
//new LocationListener(LocationManager.NETWORK_PROVIDER)
};
@Override
public IBinder onBind(Intent arg0)
{
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
Log.e(TAG, "onStartCommand");
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
@Override
public void onCreate()
{
Log.e(TAG, "onCreate");
initializeLocationManager();
/* try {
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[1]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "network provider does not exist, " + ex.getMessage());
}*/
try {
mLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[0]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "gps provider does not exist " + ex.getMessage());
}
}
@Override
public void onDestroy()
{
Log.e(TAG, "onDestroy");
super.onDestroy();
if (mLocationManager != null) {
for (int i = 0; i < mLocationListeners.length; i++) {
try {
mLocationManager.removeUpdates(mLocationListeners[i]);
} catch (Exception ex) {
Log.i(TAG, "fail to remove location listners, ignore", ex);
}
}
}
}
private void initializeLocationManager() {
Log.e(TAG, "initializeLocationManager");
if (mLocationManager == null) {
mLocationManager = (LocationManager)getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
}
}
使用位置=首先检查是否未崩溃，请在清单文件中添加访问精细和粗略位置权限，如果您完成了所有操作，请尝试一个简单的打开谷歌地图应用程序，然后它会要求启用位置，然后启动您的应用程序，您将获得位置非空，getLastLocation可能返回null，因为设备/操作系统不会自动保持最后一个位置可用。如果您确实需要最新的位置，请请求位置更新。这是一个非常常见的问题，实际上是一个功能，已经包含在几个StackOverflow问题和答案中，但我不知道哪一个最好链接到这里。
public class LocationTracking extends Service {
private static final String TAG = "BOOMBOOMTESTGPS";
private LocationManager mLocationManager = null;
private static final int LOCATION_INTERVAL = 10000;
private static final float LOCATION_DISTANCE = 0;
double latitude; // latitude
double longitude; // longitude
String emp_id=Login.strUserID;;
View view;
private class LocationListener implements android.location.LocationListener
{
Location mLastLocation;
public LocationListener(String provider)
{
Log.e(TAG, "LocationListener " + provider);
mLastLocation = new Location(provider);
}
@Override
public void onLocationChanged(Location location)
{
ConnectivityManager cn = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo nf = cn.getActiveNetworkInfo();
if (nf != null && nf.isConnected() == true) {
Log.e(TAG, "onLocationChanged: " + location);
latitude=location.getLatitude();
longitude=location.getLongitude();
SendQueryString(latitude,longitude);
Log.d("tag","lat"+latitude+"Long"+longitude+"");
Toast.makeText(LocationTracking.this,"Lat and Long"+location+"emp_id"+emp_id+"",Toast.LENGTH_LONG).show();
mLastLocation.set(location);
}else{
Toast.makeText(LocationTracking.this,"Bad network",Toast.LENGTH_LONG).show();
showErrorToast(view);
}
}
public void showErrorToast(View view) {
MDToast.makeText(LocationTracking.this, "Bad Network Connection", MDToast.LENGTH_LONG, MDToast.TYPE_ERROR);
}
@Override
public void onProviderDisabled(String provider)
{
Log.e(TAG, "onProviderDisabled: " + provider);
}
@Override
public void onProviderEnabled(String provider)
{
Log.e(TAG, "onProviderEnabled: " + provider);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
Log.e(TAG, "onStatusChanged: " + provider);
}
}
LocationListener[] mLocationListeners = new LocationListener[] {
new LocationListener(LocationManager.GPS_PROVIDER),
//new LocationListener(LocationManager.NETWORK_PROVIDER)
};
@Override
public IBinder onBind(Intent arg0)
{
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId)
{
Log.e(TAG, "onStartCommand");
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
@Override
public void onCreate()
{
Log.e(TAG, "onCreate");
initializeLocationManager();
/* try {
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[1]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "network provider does not exist, " + ex.getMessage());
}*/
try {
mLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
mLocationListeners[0]);
} catch (java.lang.SecurityException ex) {
Log.i(TAG, "fail to request location update, ignore", ex);
} catch (IllegalArgumentException ex) {
Log.d(TAG, "gps provider does not exist " + ex.getMessage());
}
}
@Override
public void onDestroy()
{
Log.e(TAG, "onDestroy");
super.onDestroy();
if (mLocationManager != null) {
for (int i = 0; i < mLocationListeners.length; i++) {
try {
mLocationManager.removeUpdates(mLocationListeners[i]);
} catch (Exception ex) {
Log.i(TAG, "fail to remove location listners, ignore", ex);
}
}
}
}
private void initializeLocationManager() {
Log.e(TAG, "initializeLocationManager");
if (mLocationManager == null) {
mLocationManager = (LocationManager)getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
}
}
try {
startService(new Intent(RegularCustomerBilling.this, LocationTracking.class));
} catch (Exception e) {
}
And in manifest mention that service
<service
android:name=".LocationTracking"
android:enabled="true"
android:exported="true" />