Apps Problem getting GPS coordinates.

[Gulam Mohammad]

Hello Developers,

I am new to Android apps development, I am trying to get the GPS coordinates but i am not able to figure it out where my code has problem. i am using android studio 1.4 version and the project is built on ICE CREAM Sandwich 4.0.3
Using some articles i tried to get the coordinates but i am always facing problem getting the coordinates.

Here is my code

This is how i am defining permission setting in my manifest.xml file

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.dell.soslocation" >

<uses-permission android:name="android.permission.INTERNET"></uses-permission>

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

</manifest>

This is my activity_main.xml file

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:fitsSystemWindows="true"
tools:context=".MainActivity">

<android.support.design.widget.AppBarLayout android:layout_height="wrap_content"
android:layout_width="match_parent" android:theme="@style/AppTheme.AppBarOverlay">

<android.support.v7.widget.Toolbar android:id="@+id/toolbar"
android:layout_width="match_parent" android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary" app:popupTheme="@style/AppTheme.PopupOverlay" />

</android.support.design.widget.AppBarLayout>

<include layout="@layout/content_main" />

<android.support.design.widget.FloatingActionButton android:id="@+id/fab"
android:layout_width="wrap_content" android:layout_height="wrap_content"
android:layout_gravity="bottom|end" android:layout_margin="@dimen/fab_margin"
android:src="@android:drawable/ic_dialog_email" />

</android.support.design.widget.CoordinatorLayout>

This is my content_main.xml file

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:showIn="@layout/activity_main" tools:context=".MainActivity">

<LinearLayout
android:id="@+id/linearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="40dip"
android:orientation="horizontal" >

<TextView
android:id="@+id/TextView01"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="Latitude: "
android:textSize="20dip" >
</TextView>

<TextView
android:id="@+id/TextView02"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="unknown"
android:textSize="20dip" >
</TextView>
</LinearLayout>

<LinearLayout
android:id="@+id/linearLayout2"
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<TextView
android:id="@+id/TextView03"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dip"
android:layout_marginRight="5dip"
android:text="Longitute: "
android:textSize="20dip" >
</TextView>

<TextView
android:id="@+id/TextView04"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="unknown"
android:textSize="20dip" >
</TextView>
</LinearLayout>
</RelativeLayout>

and finally this is my MainActivity.java file

package com.example.dell.soslocation;

import android.Manifest;
import android.annotation.TargetApi;
import android.app.Notification;
import android.content.pm.PackageManager;
import android.net.wifi.p2p.WifiP2pManager;
import android.os.Build;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;

import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements LocationListener {

private TextView latituteField;
private TextView longitudeField;
private LocationManager locationManager;
private String provider;

@TargetApi(Build.VERSION_CODES.M)
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});

latituteField = (TextView) findViewById(R.id.TextView02);
longitudeField = (TextView) findViewById(R.id.TextView04);

// Get the location manager
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Define the criteria how to select the locatioin provider -> use
// default
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// public void requestPermissions(@NonNull String[] permissions, int requestCode)
// 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 Activity#requestPermissions for more details.
return;
}
Location location = locationManager.getLastKnownLocation(provider);

// Initialize the location fields
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
onLocationChanged(location);
} else {
latituteField.setText("Location not available");
longitudeField.setText("Location not available");
}
}

/* Request updates at startup */
@TargetApi(Build.VERSION_CODES.M)
@Override
protected void onResume() {
super.onResume();
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// public void requestPermissions(@NonNull String[] permissions, int requestCode)
// 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 Activity#requestPermissions for more details.
return;
}
locationManager.requestLocationUpdates(provider, 400, 1, this);
}

/* Remove the locationlistener updates when Activity is paused */
@TargetApi(Build.VERSION_CODES.M)
@Override
protected void onPause() {
super.onPause();
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// public void requestPermissions(@NonNull String[] permissions, int requestCode)
// 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 Activity#requestPermissions for more details.
return;
}
locationManager.removeUpdates(this);
}

@Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
latituteField.setText(String.valueOf(lat));
longitudeField.setText(String.valueOf(lng));
}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}

@Override
public void onProviderEnabled(String provider) {
Toast.makeText(this, "Enabled new provider " + provider,
Toast.LENGTH_SHORT).show();

}

@Override
public void onProviderDisabled(String provider) {
Toast.makeText(this, "Disabled provider " + provider,
Toast.LENGTH_SHORT).show();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();

//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}

return super.onOptionsItemSelected(item);
}
}

There is no error i got when i ran the app in android emulator Nexus 4 Api 23 but its not displaying any coordinates, since the provider is always null. And when i install in my device its not starting and giving the error "unfortunately the app has stopped"

Can somebody tell me whats wrong in my code.

Thanks,

 

[Unforgiven]

Application Development thread moved to the Development forum for better exposure.

FWIW, I'm not a developer, but watfching this forum I've learned it is easier for others to help if you put your code inside code tags.

[code]...your code here...
...more code...
...etc...[/code]

...your code here...
...more code...
...etc...

 

[mikedt]

You're running this in an emulator on a PC? That won't have a GPS, so could be why you're not getting anything, and there's nothing wrong with your code. "provider is always null", because there's no GPS connected to it? Don't know why it's crashing on your device, I'm not a dev. either. But as @Unforgiven suggested, edit your post, and use code tags for your code, at the moment it looks like the "@"s are going to various AF member usernames, because that's what Xenforo does.

 

[Gulam Mohammad]

You're running this in an emulator on a PC? That won't have a GPS, so could be why you're not getting anything, and there's nothing wrong with your code. "provider is always null", because there's no GPS connected to it?

Hi mikedt,
Thanks for your prompt reply.
but when i am running this in my mobile the app is not working at all. its not starting and always i get this error when i open the app "unfortunately the app has stopped"

I have modified my code now its under code tags