我们如何获取该谷歌地图v2中所有路由节点的音轨

Question

在我的项目中，我需要制作一个导航应用程序来向盲人用户提供方向，所以我需要获取该Google地图中所有路线节点的音轨。我在网上参考了许多导航教程，但我没有得到我需要的东西。对于任何帮助，我感谢你。

这是我的 JSON 解析器类

public class DirectionsJSONParser {
/** Receives a JSONObject and returns a list of lists containing latitude and longitude */
public List<List<HashMap<String,String>>> parse(JSONObject jObject){
    List<List<HashMap<String, String>>> routes = new ArrayList<List<HashMap<String,String>>>() ;
    JSONArray jRoutes = null;
    JSONArray jLegs = null;
    JSONArray jSteps = null;
    try {
        jRoutes = jObject.getJSONArray("routes");
        /** Traversing all routes */
        for(int i=0;i<jRoutes.length();i++){
            jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");
            List path = new ArrayList<HashMap<String, String>>();
            /** Traversing all legs */
            for(int j=0;j<jLegs.length();j++){
                jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");
                /** Traversing all steps */
                for(int k=0;k<jSteps.length();k++){
                    String polyline = "";
                   // polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("formatted_address");
                    polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
                    List<LatLng> list = decodePoly(polyline);
                    /** Traversing all points */
                    for(int l=0;l<list.size();l++){
                        HashMap<String, String> hm = new HashMap<String, String>();
                        hm.put("lat", Double.toString(((LatLng)list.get(l)).latitude) );
                        hm.put("lng", Double.toString(((LatLng)list.get(l)).longitude) );
                        path.add(hm);
                    }
                }
            routes.add(path);
        }
    }
} catch (JSONException e) {
    e.printStackTrace();
}catch (Exception e){
}
return routes;
}
/**
* Method to decode polyline points
* Courtesy : http://jeffreysambells.com/2010/05/27/decoding-polylines-from-google-maps-direction-api-with-java
* */
private List<LatLng> decodePoly(String encoded) {
    List<LatLng> poly = new ArrayList<LatLng>();
    int index = 0, len = encoded.length();
    int lat = 0, lng = 0;
    while (index < len) {
        int b, shift = 0, result = 0;
        do {
            b = encoded.charAt(index++) - 63;
            result |= (b & 0x1f) << shift;
            shift += 5;
        } while (b >= 0x20);
        int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
        lat += dlat;
        shift = 0;
        result = 0;
        do {
            b = encoded.charAt(index++) - 63;
            result |= (b & 0x1f) << shift;
            shift += 5;
        } while (b >= 0x20);
        int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
        lng += dlng;
        LatLng p = new LatLng((((double) lat / 1E5)),
            (((double) lng / 1E5)));
        poly.add(p);
    }
    return poly;
}

}

Answer 1

没有

方向的音轨，但是看起来您正在使用Google Directions API如果您查看文档，您会看到路线的说明在 JSON 中作为html_instructions返回给您。

然后你要做的是使用说明并使用Text To Speech (TTS)引擎说出来。

然而

按照TOS中所述forbidden使用方向 API 作为逐向导航

Google Maps/Google Earth APIs Terms of Service
Last updated: May 27, 2009
...
10. License Restrictions. Except as expressly permitted under the Terms, or unless you
have received prior written authorization from Google (or, as applicable, from the
provider of particular Content), Google's licenses above are subject to your adherence
to all of the restrictions below. Except as explicitly permitted in Section 7 or the
Maps APIs Documentation, you must not (nor may you permit anyone else to):
...
10.9 use the Service or Content with any products, systems, or applications for or in
connection with:
(a) real time navigation or route guidance, including but not limited to turn-by-turn
route guidance that is synchronized to the position of a user's sensor-enabled device;
and may be disabled for certain apps (somehow, at least on Android)... FromGeocode
scraping in .NET conversation:
This is not allowed by the API terms of use. You should not scrape Google Maps to
generate geocodes. We will block services that do automated queries of our servers.
Bret Taylor
Product Manager, Google Maps