I am trying to implement a location alarm kind of application. But whenever my application opens. my current location shows as null.
Below is my code.
package com.hrupin;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class HelloAndroidGpsActivity extends Activity implements OnClickListener, android.content.DialogInterface.OnClickListener, LocationListener {
private TextView setLat, setLong, destLat, destLong, currLat, currLong, tjd, fromhome, toward;
private Button setmyLoc, setDest;
private EditText editLat, editLong;
private LocationManager orgManager;
//private LocationListener orgListener;
// private LocationListener destListener = new destListener();
private boolean gps_enabled = false;
private boolean network_enabled = false;
private String bestProvider;
double orginLongitude, orginLatitude, destLongtitude, destLatitude, currLatitude, currLongtitude;
float firstLat, firstLang, secLat, secLang;
Location destinationLocation = new Location("gps");
Location originLocation = new Location("gps");
Location currLocation = new Location("gps");
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
setLat = (TextView) findViewById(R.id.setLat);
setLong = (TextView) findViewById(R.id.setLong);
destLat = (TextView) findViewById(R.id.destLat);
destLong = (TextView) findViewById(R.id.destLong);
currLat = (TextView) findViewById(R.id.currLat);
currLong = (TextView)findViewById(R.id.currLong);
tjd = (TextView)findViewById(R.id.setmeter);
fromhome = (TextView)findViewById(R.id.destmeter);
toward = (TextView)findViewById(R.id.currmeter);
setDest = (Button)findViewById(R.id.SetLocation);
editLat = (EditText)findViewById(R.id.editLat);
editLong = (EditText)findViewById(R.id.editLong);
orgManager = (LocationManager)this.getSystemService(Context.LOCATION_SERVICE);
try {
gps_enabled = orgManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
} catch (Exception ex) {
Log.i("gps_enabled", ex.toString());
}
try {
network_enabled = orgManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
} catch (Exception ex) {
Log.i("network_enabled", ex.toString());
}
// don't start listeners if no provider is enabled
if (!gps_enabled && !network_enabled) {
AlertDialog.Builder builder = new Builder(
HelloAndroidGpsActivity.this);
builder.setTitle("Attention!");
builder.setMessage("Sorry, location is not determined. Please enable location providers");
builder.setPositiveButton("OK",
HelloAndroidGpsActivity.this);
builder.setNeutralButton("Cancel",
HelloAndroidGpsActivity.this);
builder.create().show();
}
Criteria criteria = new Criteria();
bestProvider = orgManager.getBestProvider(criteria, false);
orgManager.requestLocationUpdates(bestProvider, 0, 0, this);
Location location = orgManager.getLastKnownLocation(bestProvider);
if (location!=null){
setLat.setText("Latitude:" + currLatitude);
setLong.setText("Longitude:" + currLongtitude);
originLocation.setLatitude(currLatitude);
originLocation.setLongitude(currLongtitude);
}
//else Toast.makeText(getBaseContext(), "Error in GPS", Toast.LENGTH_SHORT).show();
setDest.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
destLat.setText("Lat:"+editLat.getText().toString().trim());
destLong.setText("Long"+editLong.getText().toString().trim());
destLatitude = Double.parseDouble(String.valueOf(editLat.getText().toString().trim()));
destLongtitude = Double.parseDouble(String.valueOf(editLong.getText().toString().trim()));
destinationLocation.setLatitude(destLatitude);
destinationLocation.setLongitude(destLongtitude);
float distance = originLocation.distanceTo(destinationLocation);
tjd.setText(String.valueOf(distance/1000)+ " Kms ");
}
});
}
/** Register for the updates when Activity is in foreground */
@Override
protected void onResume() {
super.onResume();
orgManager.requestLocationUpdates(bestProvider, 60000, 1, this);
}
/** Stop the updates when Activity is paused */
@Override
protected void onPause() {
super.onPause();
orgManager.removeUpdates(this);
}
public void onClick(DialogInterface dialog, int which) {
if (which == DialogInterface.BUTTON_NEUTRAL) {
setLat.setText("Sorry, location is not determined. To fix this please enable location providers");
} else if (which == DialogInterface.BUTTON_POSITIVE) {
startActivity(new Intent(
android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS));
}
}
public void onClick(View v) {
// TODO Auto-generated method stub
}
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
if (location != null) {
// This needs to stop getting the location data and save the
// battery power.
//orgManager.removeUpdates(orgListener);
currLatitude = location.getLatitude();
currLongtitude = location.getLongitude();
currLocation.setLatitude(currLatitude);
currLocation.setLongitude(currLongtitude);
currLat.setText(String.valueOf(currLatitude));
currLong.setText(String.valueOf(currLongtitude));
float fromhome = originLocation.distanceTo(currLocation);
float toward = currLocation.distanceTo(destinationLocation);
HelloAndroidGpsActivity.this.fromhome.setText(String.valueOf(fromhome/1000)+ " Kms ");
HelloAndroidGpsActivity.this.toward.setText(String.valueOf(toward/1000) + " Kms ");
if (toward/1000 <= 14 ){
Toast.makeText(getBaseContext(), "You are "+ toward/1000 + " Kms towards Destination ", Toast.LENGTH_SHORT).show();
}
}
}
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
I know this kind of question has been million times. I have tried all methods which has been specified in answers. But i havent got any output. Please help.
You should not call requestLocationUpdates on onCreate as it is redundant since your code will call it on onResume. The flow is onCreate --> onStart --> onResume.