為什麼使用 KML 資料來擷取 Android 版 Google 路線不再有效？
簡介
以前，可以使用 Android 應用程式的 KML 資料檢索 Google 路線。不過，此方法不再受支援。
停止原因
Google 更改了其 Directions API 的結構，因此有必要遷移到 JSON 或 XML資料檢索。 KML 不再可用於此目的。
解決方案
有兩種解決方案可以解決此問題：
遷移到JSON
JSON 解析的程式碼片段
JSON 解析的程式碼片段
public interface Parser {
public Route parse();
}這裡是用Java 解析JSON方向資料的程式碼片段類別：
Parser.javapublic 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();
}
}XMLParser.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;
}
}XMLParser.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;
}
}Route.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;
}
}以上是為什麼 Google Directions KML 資料檢索不再適用於 Android 應用程式？的詳細內容。更多資訊請關注PHP中文網其他相關文章！
