App crashes when getting the distance from two latitude and longitude

Question

I'm new to android and I'm creating an app that will calculate the distance base from starting latitude and longitude to current latitude and longitude. Below is my code on getting the distance from latitude and longitude where start means starting and curr means current. (I just copied the formula on how to get the distance from two latitude and longitude on the internet)

public Double getDistance(Double startLat, Double startLong, Double currLat, Double currLong) {

    int radius = 6371; //This is the radius of the earth
    Double distanceLatitude = degreeToRadius(currLat-startLat);
    Double distanceLongitude = degreeToRadius(currLong-startLong);
    Double area =
            Math.sin(distanceLatitude/2) * Math.sin(distanceLatitude/2) +
                    Math.cos(degreeToRadius(startLat)) * Math.cos(degreeToRadius(currLat)) *
                            Math.sin(distanceLongitude/2) * Math.sin(distanceLongitude/2)
            ;
    Double circumference = 2 * Math.atan2(Math.sqrt(area), Math.sqrt(1-area));
    Double totalDistance = radius * circumference;
    return totalDistance;

}

public Double degreeToRadius(Double degreeToRadius) {
    return degreeToRadius * (Math.PI/180);
}

And this is my onLocationChanged function where it updates the latitude and longitude when the device has been moved and I am also setting the distance here.

@Override
public void onLocationChanged(Location location) {

    String locationMessage = "Latitude: " + location.getLatitude()
            + "Longitude: " + location.getLongitude();

    Double locationLatitude = location.getLatitude();
    Double locationLongitude = location.getLongitude();

    Toast.makeText(getBaseContext(), locationMessage, Toast.LENGTH_LONG).show();
    currentLatitude.setText(locationLatitude.toString());
    currentLongitude.setText(locationLongitude.toString());

    Double startLat = Double.parseDouble(startingLatitude.getText().toString());
    Double startLong = Double.parseDouble(startingLongitude.getText().toString());
    Double currLat = Double.parseDouble(currentLatitude.getText().toString());
    Double currLong = Double.parseDouble(currentLongitude.getText().toString());

    distance.setText(getDistance(startLat, startLong, currLat, currLong).toString() + "KM");

}

Whenever I launch the app, It functions normally but when it start getting the location, It always crashes. Any idea? Please help. Thanks

This is the log

E/AndroidRuntime: FATAL EXCEPTION: main
              Process: com.example.webglider.fitnessapp, PID: 7600
              java.lang.NumberFormatException: Invalid double: ""
                  at java.lang.StringToReal.invalidReal(StringToReal.java:63)
                  at java.lang.StringToReal.parseDouble(StringToReal.java:267)
                  at java.lang.Double.parseDouble(Double.java:301)
                  at com.example.webglider.fitnessapp.MainActivity.onLocationChanged(MainActivity.java:196)
                  at android.location.LocationManager$ListenerTransport._handleMessage(LocationManager.java:290)
                  at android.location.LocationManager$ListenerTransport.access$000(LocationManager.java:219)
                  at android.location.LocationManager$ListenerTransport$1.handleMessage(LocationManager.java:235)
                  at android.os.Handler.dispatchMessage(Handler.java:102)
                  at android.os.Looper.loop(Looper.java:148)
                  at android.app.ActivityThread.main(ActivityThread.java:7325)
                  at java.lang.reflect.Method.invoke(Native Method)
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

This is the line 196 on my MainActivity.java

Double startLat = Double.parseDouble(startingLatitude.getText().toString());

try this http://stackoverflow.com/questions/22577075/calculating-the-distance-between-two-latitude-and-longitude-points-in-android — D.J, Oct 19 '16 at 06:52
Man what is all of this, you dont need any of this there is a simple function that calculate the distance between tow locations `double distance=location1.distanceTo(location2)` — Mohammad Haidar, Oct 19 '16 at 06:56

score 0 · Answer 1 · answered Oct 19 '16 at 06:57

Try the below code. Location class in android has built in method to get the distance between two locations. This will provide you the distance in meters.

Location oldLocation = new Location("oldLocation");     
oldLocation.setLatitude(oldLat); 
oldLocation.setLongitude(oldLng);
Location newLocation = new Location("newLocation");
newLocation.setLatitude(newLat); 
newLocation.setLongitude(newLng);
float distance = oldLocation.distanceTo(newLocation) ;

For the reference check the official documentation.https://developer.android.com/reference/android/location/Location.html#distanceTo(android.location.Location)

App crashes when getting the distance from two latitude and longitude

1 Answers1