我有一个显示用户所在位置的地图活动，当我第一次打开活动时一切都很好，但是如果我去其他地方再次打开活动，则不会显示用户所在的位置只是欧洲地图（所以我想它不能识别GPS）。这是这个的代码
public class Map extends AppCompatActivity implements LocationListener, OnMapReadyCallback, NavigationView.OnNavigationItemSelectedListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.map);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayShowTitleEnabled(false);
toolbar.setTitle("");
toolbar.setSubtitle("");
//gpsStatus = (TextView) findViewById(R.id.gpsStatus);
dis = (TextView) findViewById(R.id.distancePreview);
newActL = (RelativeLayout) findViewById(R.id.newAct);
startActL = (RelativeLayout) findViewById(R.id.Act);
timer = (TextView) findViewById(R.id.timePreview);
newActB = (ImageButton) findViewById(R.id.newActB);
stopActB = (ImageButton) findViewById(R.id.stopActB);
gearMap = (ImageButton) findViewById(R.id.gearmap);
List<String> spinnerArray = new ArrayList<String>();
spinnerArray.add("Arrival");
spinnerArray.add("Departure");
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
this, android.R.layout.simple_spinner_item, spinnerArray);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
sItems = (Spinner) findViewById(R.id.ardep);
sItems.setAdapter(adapter);
List<String> spinnerArray2 = new ArrayList<String>();
spinnerArray2.add("Running");
spinnerArray2.add("Walking");
spinnerArray2.add("Cycling");
spinnerArray2.add("Roller skating");
spinnerArray2.add("Skateboarding");
spinnerArray2.add("Kickbiking");
spinnerArray2.add("Teleporting");
ArrayAdapter<String> adapter2 = new ArrayAdapter<String>(
this, android.R.layout.simple_spinner_item, spinnerArray2);
adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
actCombo = (Spinner) findViewById(R.id.actCombo);
actCombo.setAdapter(adapter2);
Calendar rightNow = Calendar.getInstance();
int currentHour = rightNow.get(Calendar.HOUR_OF_DAY);
if (currentHour < 12) {
actCombo.setSelection(GetInfo.arract - 1);
sItems.setSelection(0);
} else {
actCombo.setSelection(GetInfo.depact - 1);
sItems.setSelection(1);
}
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
3000,
1, this);
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.mapview);
mapFragment.getMapAsync(this);
line = new PolylineOptions().width(3).color(Color.BLUE);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.addDrawerListener(toggle);
toggle.syncState();
navigationView = (NavigationView) findViewById(R.id.nav_view);
headerView = navigationView.getHeaderView(0);
fullnameside = (TextView) headerView.findViewById(R.id.fullnameside);
emailside = (TextView) headerView.findViewById(R.id.emailside);
fullnameside.setText("" + GetInfo.fullname);
emailside.setText("" + GetInfo.email);
navigationView.setNavigationItemSelectedListener(this);
navigationView.getMenu().getItem(1).setChecked(true);
}
private void getLocation() {
//Toast.makeText(getBaseContext(), "e paides", Toast.LENGTH_SHORT).show();
String locationProvider = LocationManager.NETWORK_PROVIDER;
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
Location location = locationManager.getLastKnownLocation(locationProvider);
try {
line.add(new LatLng(location.getLatitude(), location.getLongitude()));
GMap.addMarker(new MarkerOptions().position(new LatLng(location.getLatitude(), location.getLongitude())).title(""));
GMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(location.getLatitude(), location.getLongitude()), 16.0f));
steps++;
getloc = true;
} catch (NullPointerException e) {
//Toast.makeText(this.getBaseContext(), "gyhg" + e.toString(), Toast.LENGTH_LONG).show();
}
}
public void StopTrip(View v) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Stop and upload your trip?")
.setCancelable(true)
.setNegativeButton("NO", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
})
.setPositiveButton("YES", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
float finalDistance = (float) (distance / 1000.0);
if (finalDistance < 2) {
Intent myIntent = new Intent(Map.this, Profile.class);
startActivity(myIntent);
}
TimeBuff += MillisecondTime;
handler.removeCallbacks(runnable);
// newActL.setVisibility(View.GONE);
// startActL.setVisibility(View.VISIBLE);
enabledActivity = false;
//database post
try {
Date currentTime = Calendar.getInstance().getTime();
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
String formattedDate = df.format(currentTime);
Date currentTime2 = Calendar.getInstance().getTime();
SimpleDateFormat df2 = new SimpleDateFormat("yyyy-MM-dd%20HH:mm:ss");
dateActEnd = df2.format(currentTime2);
String act = actCombo.getSelectedItem().toString();
String act_id = "7";
switch (act) {
case "Running":
act_id = "1";
break;
case "Walking":
act_id = "2";
break;
case "Cycling":
act_id = "3";
break;
case "Roller skating":
act_id = "4";
break;
case "Skateboarding":
act_id = "5";
break;
case "Kickbiking":
act_id = "6";
break;
case "Teleporting":
act_id = "7";
break;
}
String direcor;
if (sItems.getSelectedItem().toString().equals("Arrival"))
direcor = "arrival";
else
direcor = "departure";
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
// String.format("%.1f", finalDistance)
URL obj = new URL("https://gekon.technologypark.cz/api/v1/record/create?user=" + LoginInfo.UserID
+ "&date=" + formattedDate + "&distance=" + String.format("%.1f", finalDistance) + "&direction=" + direcor
+ "&activity=" + act_id + "&polyline=" + PolyUtil.encode(line.getPoints()) + "&start=" + dateActStart
+ "&end=" + dateActEnd + "&source=mobileapp");
HttpsURLConnection conn = (HttpsURLConnection) obj.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("ApiSecret", LoginInfo.ApiSecret);
conn.connect();
BufferedReader br = new BufferedReader(new InputStreamReader((conn.getInputStream())));
StringBuilder sb = new StringBuilder();
String output;
while ((output = br.readLine()) != null)
sb.append(output);
JSONObject jsonObj = new JSONObject(sb.toString());
JSONObject curRecord = new JSONObject(jsonObj.getString("data"));
Trips.datet.add(currentTime);
Trips.datestr.add(formattedDate);
Trips.act.add(act_id);
Trips.tripType.add(sItems.getSelectedItem().toString());
Trips.dist.add(String.format("%.1f", finalDistance));
Trips.trip_ids.add(curRecord.getString("trip_id"));
Trips.calc(++Trips.points);
TripsCalendarInfo.datet.add(currentTime);
TripsCalendarInfo.act.add(act_id);
TripsCalendarInfo.act_str.add(act);
TripsCalendarInfo.tripType.add(sItems.getSelectedItem().toString());
TripsCalendarInfo.dist.add(String.format("%.1f", finalDistance));
TripsCalendarInfo.datestr.add(formattedDate);
TripsCalendarInfo.trip_ids.add(curRecord.getString("trip_id"));
TripsCalendarInfo.trip_source.add("mobileapp");
TripsCalendarInfo.polyline.add(PolyUtil.encode(line.getPoints()));
TripsCalendarInfo.CanItrip();
float km_up = Float.parseFloat(TripsInfo.km.get(TripsInfo.userRank - 1)) + finalDistance;
int trip_up = Integer.parseInt(TripsInfo.trips.get(TripsInfo.userRank - 1)) + 1;
TripsInfo.trips.set(TripsInfo.userRank - 1, "" + trip_up);
TripsInfo.km.set(TripsInfo.userRank - 1, String.format("%.1f", km_up));
TripsInfo.rankSort();
getloc = false;
Intent myIntent = new Intent(Map.this, Profile.class);
startActivity(myIntent);
} catch (Exception e) {
Toast.makeText(getBaseContext(), "Error upload, please check your options at gear button", Toast.LENGTH_LONG).show();
}
}
});
float finalDistance = (float) (distance / 1000.0);
if (finalDistance < 2) {
builder.setMessage("Your trip is below 2km and it will not be counted.\nAre you sure you want to stop?");
}
AlertDialog alert = builder.create();
alert.show();
}
public void StartAct(View v) {
timer.setVisibility(View.VISIBLE);
dis.setVisibility(View.VISIBLE);
newActB.setVisibility(View.GONE);
stopActB.setVisibility(View.VISIBLE);
//gearMap.setVisibility(View.GONE);
navigationView.setVisibility(View.GONE);
//headerView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
toolbar.setNavigationIcon(null); // to hide Navigation icon
//toolbar.setDisplayHomeAsUpEnabled(false);
handler = new Handler();
Date currentTime = Calendar.getInstance().getTime();
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd%20HH:mm:ss");
dateActStart = df.format(currentTime);
StartTime = SystemClock.uptimeMillis();
handler.postDelayed(runnable, 0);
startService(new Intent(this, LocationService.class));
//enabledActivity = true;
}
public void ChangeAct(View v) {
if (newActL.getVisibility() == View.GONE) {
newActL.setVisibility(View.VISIBLE);
startActL.setVisibility(View.GONE);
} else {
newActL.setVisibility(View.GONE);
startActL.setVisibility(View.VISIBLE);
}
}
public Runnable runnable = new Runnable() {
public void run() {
MillisecondTime = SystemClock.uptimeMillis() - StartTime;
UpdateTime = TimeBuff + MillisecondTime;
Seconds = (int) (UpdateTime / 1000);
Minutes = Seconds / 60;
Hours = Minutes / 60;
Seconds = Seconds % 60;
Minutes = Minutes % 60;
MilliSeconds = (int) (UpdateTime % 100);
timer.setText("Time: " + String.format("%02d", Hours) + ":"
+ String.format("%02d", Minutes) + ":"
+ String.format("%02d", Seconds));
handler.postDelayed(this, 950);
}
};
@Override
public void onMapReady(GoogleMap map) {
GMap = map;
GMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(49.8117806, 15.6970293), 6.0f));
if (!getloc)
getLocation();
}
答案 0 :(得分：1)
我还没有仔细研究过您的代码，但是您确定要调用方法来获取活动onResume上的位置吗？从后台返回您的活动的onCreate不会被调用，因此不会调用您的getLocation（）方法。