How do I fix this distanceBetween method syntax for Android?

Question

Hi I am trying to implement the distanceBetween method from http://developer.android.com/reference/android/location/Location.html#distanceBetween(double, double, double, double, float[]).

I am new to coding so I believe I am making this harder than it should be but I am not sure why. I am attempting to source that JSON Object and grab the information from FIeld1(callsign), Field2(frequency),Field21(latitude),Field24(latitude). Then I want to run the distanceBetween to find out if it is within a radius of say 350 KM. Can anyone help me with some hints or code please? Thanks!

Here is my UPDATED MainActivity.java

    package com.dredaydesigns.radiostationfinder;

import android.R;
import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.location.Location;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationServices;
import com.squareup.okhttp.Call;
import com.squareup.okhttp.Callback;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import butterknife.Bind;
import butterknife.ButterKnife;


public class MainActivity extends Activity implements GoogleApiClient.ConnectionCallbacks {
    public static final String TAG = MainActivity.class.getSimpleName();
    private RadioData mRadioData;

    private GoogleApiClient mGoogleApiClient;
    private Location mLastLocation;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.list_content);
        ButterKnife.bind(this);


        Location locationUserLatitude = mLastLocation;
        Location locationUserLongitude = mLastLocation;
        Location latitudeStation;
        Location longitudeStation;
        RadioData mRadioData = new RadioData();

        OkHttpClient client = new OkHttpClient();
        String radioFinderURL = "http://dredaycreative.com/json/radioData.json";
        Request request = new Request.Builder()
                .url(radioFinderURL)
                .build();
        Call call = client.newCall(request);
        call.enqueue(new Callback() {
            @Override
            public void onFailure(Request request, IOException e) {
            }

            @Override
            public void onResponse(Response response) throws IOException {
                try {
                    String jsonData = response.body().string();
                    Log.v(TAG, jsonData);
                    if (response.isSuccessful()) {
                        getCurrentRadioData(jsonData);
                    }

                } catch (IOException e) {
                    Log.e(TAG, "Exception Caught: ", e);
                } catch (JSONException e) {
                    Log.e(TAG, "Exception Caught:", e);
                }
            }

        });


    }


    private List getCurrentRadioData(String jsonData) throws JSONException{
        List radioData = new ArrayList();
        Object obj=JSONValue.parse(jsonData);
        JSONArray data;
        data = (JSONArray)obj;
        for (int i=0; i



this is the jsonValue.java i grabbed from someone on github

  package com.dredaydesigns.radiostationfinder;

/*
 * $Id: JSONValue.java,v 1.1 2006/04/15 14:37:04 platform Exp $
 * Created on 2006-4-15
 */

import org.json.simple.parser.JSONParser;

import java.io.Reader;
import java.io.StringReader;


/**
 * @author FangYidong
 */
public class JSONValue {
    /**
     * parse into java object from input source.
     * @param in
     * @return instance of : JSONObject,JSONArray,String,Boolean,Long,Double or null
     */
    public static Object parse(Reader in){
        try{
            JSONParser parser=new JSONParser();
            return parser.parse(in);
        }
        catch(Exception e){
            return null;
        }
    }

    public static Object parse(String s){
        StringReader in=new StringReader(s);
        return parse(in);
    }
}


this is the XML



    

    




and this is the getter and setters RadioData.java... I am kind of piecing this project of my own together from what I learned  from teamtreehouse so apologize if it is very tacky.

 package com.dredaydesigns.radiostationfinder;

/**
 * Created by Andreas on 8/10/2015.
 */
public class RadioData {
    public String getCallSign() {
        return mCallsign;
    }

    public void setCallSign(String callsign) {
        mCallsign = callsign;
    }

    public double getFrequency() {
        return mFrequency;
    }

    public void setFrequency(double frequency) {
        mFrequency = frequency;
    }

    public int getChannel() {
        return mChannel;
    }

    public void setChannel(int channel) {
        mChannel = channel;
    }

    public double getLatitude() {
        return mLatitude;
    }

    public void setLatitude(double latitude) {
        mLatitude = latitude;
    }

    public double getLongitude() {
        return mLongitude;
    }

    public void setLongitude(double longitude) {
        mLongitude = longitude;
    }

    private String mCallsign;
    private double mFrequency;
    private int mChannel;
    private double mLatitude;
    private double mLongitude;



}


after suggestions from user I have now had this portion of the MainActivity code changed to the following, but it seems to still be wrong somewhere and I need help, thanks! my gradle is building fine but I cannot get genymotion to work so I am unable to know what is working or not! if this part is working okay the next step for me would be to display that localRadioData to the user :D 
:

 private List getCurrentRadioData() throws JSONException{
        List radioData = new ArrayList();
        List localRadioData = new ArrayList();
        Object obj=JSONValue.parse(String.valueOf(radioData));
        JSONArray data;
        data = (JSONArray)obj;
        float[] results = new float[3];
        double latitudeStation = 0;
        double longitudeStation = 0;
        for (int i=0; i 350) {
                JSONObject callsign = jasonObj.getJSONObject("FIELD1");
                localRadioData.add(callsign);
                JSONObject frequency = jasonObj.getJSONObject("FIELD2");
                localRadioData.add(frequency);
            } else {
            radioData.add(getCurrentRadioData());

            }


        }

        return localRadioData;
    }

edkek · Accepted Answer

distanceBetween is a static function of the Location class, meaning you can simply call it by doing the following:

float[] results = new float[3];
Location.distanceBetween(startLat, startLong, endLat, endLong, results);
float distance = results[0];

In terms of how to implement it in your code, it may look like something like this:

float[] results = new float[3];
Location.distanceBetween(mLastLocation.getLatitude(), mLastLocation.getLongitude(), latitudeStation, longitudeStation, results);
float distance = results[0];

I hope this helped :)

How do I fix this distanceBetween method syntax for Android?

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