Why is Google Directions KML data retrieval no longer working for Android apps?

Why is retrieving Google Directions for Android using KML data no longer working?

Introduction

Previously, it was possible to retrieve Google Directions using KML data for Android applications. However, this method is no longer supported.

Reason for Discontinuation

Google has changed the structure of its Directions API, making it necessary to migrate to JSON or XML for data retrieval. KML is no longer available for this purpose.

Solutions

There are two solutions to address this issue:

1. Migrate to JSON

   • Create Java classes to parse JSON data as demonstrated in the code snippets below.
   • Use these classes to retrieve and parse JSON directions data.

2. Alternatives

   • Consider using other mapping services that provide KML data.
   • Explore using Google's Places API or Directions API directly.

Code Snippets for JSON Parsing

Here are code snippets for parsing JSON directions data using Java classes:

Parser.java

public interface Parser {
  public Route parse();
}

XMLParser.java

public abstract class XMLParser implements Parser {
  protected URL feedUrl;

  protected XMLParser(String feedUrl) throws MalformedURLException {
    this.feedUrl = new URL(feedUrl);
  }

  protected InputStream getInputStream() throws IOException {
    return feedUrl.openConnection().getInputStream();
  }
}

Segment.java

public class Segment {
  private GeoPoint start;
  private String instruction;
  private int length;
  private double distance;

  public Segment() {}

  public void setInstruction(String instruction) {
    this.instruction = instruction;
  }

  public String getInstruction() {
    return instruction;
  }

  public void setPoint(GeoPoint point) {
    start = point;
  }

  public GeoPoint startPoint() {
    return start;
  }
}

Route.java

public class Route {
  private String name;
  private List<GeoPoint> points = new ArrayList<>();
  private List<Segment> segments = new ArrayList<>();
  private String copyright;
  private String warning;
  private String country;
  private int length;
  private String polyline;

  public void addPoint(GeoPoint p) {
    points.add(p);
  }

  public List<GeoPoint> getPoints() {
    return points;
  }

  public void addSegment(Segment s) {
    segments.add(s);
  }

  public List<Segment> getSegments() {
    return segments;
  }
}

GoogleParser.java

public class GoogleParser extends XMLParser {
  private int distance;

  public GoogleParser(String feedUrl) throws MalformedURLException {
    super(feedUrl);
  }

  public Route parse() {
    // Convert stream to string
    String result = convertStreamToString(getInputStream());

    // Create route object
    Route route = new Route();
    Segment segment = new Segment();

    // Parse JSON object
    try {
      JSONObject json = new JSONObject(result);
      JSONObject jsonRoute = json.getJSONArray("routes").getJSONObject(0);
      JSONObject leg = jsonRoute.getJSONArray("legs").getJSONObject(0);
      JSONArray steps = leg.getJSONArray("steps");
      int numSteps = steps.length();

      route.setName(leg.getString("start_address") + " to " + leg.getString("end_address"));
      route.setCopyright(jsonRoute.getString("copyrights"));
      route.setLength(leg.getJSONObject("distance").getInt("value"));
      if (!jsonRoute.getJSONArray("warnings").isNull(0)) {
        route.setWarning(jsonRoute.getJSONArray("warnings").getString(0));
      }

      // Parse steps
      for (int i = 0; i < numSteps; i++) {
        JSONObject step = steps.getJSONObject(i);
        JSONObject start = step.getJSONObject("start_location");
        GeoPoint position = new GeoPoint((int) (start.getDouble("lat") * 1E6), (int) (start.getDouble("lng") * 1E6));
        segment.setPoint(position);
        int stepLength = step.getJSONObject("distance").getInt("value");
        distance += stepLength;
        segment.setLength(stepLength);
        segment.setDistance(distance / 1000);
        segment.setInstruction(step.getString("html_instructions").replaceAll("<(.*?)>", ""));
        route.addPoints(decodePolyLine(step.getJSONObject("polyline").getString("points")));
        route.addSegment(segment.copy());
      }
    } catch (JSONException e) {
      Log.e(e.getMessage(), "Google JSON Parser - " + feedUrl);
    }
    return route;
  }
}

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