如何从Google方向获取polyline

Question

我试图使用Google方向Api绘制一个折线，但是如何使用JSON值来实现这一点，因为在api中有很多lat、long和polylines.points，如下所示：

cxwnFtdct@JEVGLCR?PDTFNHTNNNPJPDRDN?JCHCv@i@VQTK`CkF

我不知道我该用哪一个，有人能帮我吗？)

{
  geocoded_waypoints: [
    {},
    {}
  ],
  routes: [
    {
      bounds: {
        northeast: {
          lat: 39.2846595,
          lng: -8.7036795
        },
        southwest: {
          lat: 38.7223249,
          lng: -9.1393372
        }
      },
      copyrights: "Dados do mapa ©2017 Google, Inst. Geogr. Nacional",
      legs: [
        {
          distance: {},
          duration: {},
          end_address: "Lisboa, Portugal",
          end_location: {
            lat: 38.7223249,
            lng: -9.1393372
          },
          start_address: "Santarém, Portugal",
          start_location: {
            lat: 39.2846595,
            lng: -8.7049071
          },
          steps: [
            {
              distance: {},
              duration: {},
              end_location: {
                lat: 39.2822117,
                lng: -8.7036403
              },
              html_instructions: "Siga <b>sul</b> em direção a <b>N3</b>",
              polyline: {
                points: "cxwnFtdct@JEVGLCR?PDTFNHTNNNPJPDRDN?JCHCv@i@VQTK`CkF"
              },
              start_location: {
                lat: 39.2846595,
                lng: -8.7049071
              },
              travel_mode: "DRIVING"
            },
            {},
          ],
          traffic_speed_entry: [],
          via_waypoint: []
        }
      ],
      overview_polyline: {   points:"cxwnFtdct@dAQlAf@fAf@|Aq@l@]pCcFhCjA|LfJlAT~@IpDi@jAb@f@HXi@t@kBhBeBx@Qz@z@dClHzFpW`H|RvTpj@`AxAdBdAnAXhB?fBk@rAcAnG_HhCgAjAKrATbA`Al@lBHnAc@rFgBhIkCxMBfIlBvHnBtCnB|AnEdCrJxFj@fB@h@OhAgCtHGfCl@jAlA\jE]tDBzBb@tLxFtK~E`d@hShIzEtDhDxDrEfDpFlFjNvDtRdDjThF`TzH`QhEhG|EvFhL`JpJtE|LpEdOpFjOzGlPfJlHzE~NjLfQvPfP|RtHrKxDjGfI|NdHbOvGjPfCbHpCtIvJh_@vG|[|CtNvFvSvE~MfI|QzLbTfNxQbKlKrRzP|NnNvNlQjIzMnLfV`T|h@nDbHhIdMxFjH~JrMnEfHzIrQfHvOtEjI|MnQfNzP`FzI~EnLrKp[nDlHvErHzL~MbRbM`EjCjFxEtRnX|D~EjIhI~WrRxGlGdFnG`JjNxHzKfTxVfKfRfMbRlErHtBlFxIjYvHnPpBtFxF~WpCjHjGhJfDzClF~CnDlArDl@pC\vHXvX[lOaB|GcBdFqBxQwJbDmAxE_ApJ_@jEXtItBrQ~EbQbDlUfBpMfA|IxCbF`DhGlGnJjKtJrF`SpFbRnDdUxAbGrAlEjBnFpDtNnMfGlE~[lTbRdQjTpUxH`GjHfEnGlC`O|DrUxEnEzAfFrBnSpIjPnDxSlAf\lAl~@hDzRrAjOpBvKrBrQtEv^pM``@rPrR|JxSdMlGnGfGtH~HxFdFlBtGfApGp@bG|AnHxD|FzFrH`L~FvH|HrFrFtBtFjA~Mt@pHR|FhA`IfDpEbDzFxGrHrKhEtErF`EnS`MzMvItSdUfF~DtE~B|SrInEnBzDtCxN`QpQfVtQ~Yjn@~fAnK`RvLlRzEjF|GlFrc@vUfRjKfIvGxDhEjIxKdN~T`L~MrFvE~LhIlp@fb@xCtBzFtFbEzFbDrGhH`TfF|JnGfHzEdD|UdIpTdHtKtFj]nUrEzC~[pTfLfG|EbB~KfCnTvDpmAxSzs@~LhOfDzOdFfOxGdY`O`k@zYnVzMlK|HrFjFbXj[rCbCvDfB|FfBbD^xRBlb@nBrIdArJvDfD|B|FzFvFzHnCbIDrCk@dA_A_@q@mHz@sAvAJ^f@r@n@x@UR_@fBGjET`S~@ro@pCpXpAfFp@dEhCnGtE@HXl@n@H^W|ASpShAbZxAtPp@~SjAzGZKdDStBd@x@dC@nEVz@HtAp@b@\OZ|AbBxDnFJf@"
      },
      summary: "A1",
      warnings: [],
      waypoint_order: []
    }
  ],
  status: "OK"
}

Answer 1

将overview_polyline转换为LatLng列表并在地图中添加为多边形

使用谷歌提供的PolyUtil。

https://github.com/googlemaps/android-maps-utils/blob/master/demo/src/com/google/maps/android/utils/demo/PolyDecodeDemoActivity.java

https://github.com/googlemaps/android-maps-utils/blob/master/library/src/com/google/maps/android/PolyUtil.java

Answer 2

Check Google API实用程序库有一些解析polyline的预定义方法，还有更多。

Answer 3

我已经把我的答案放到了一个帖子上，其中也包含了你的答案。您还可以找到Parser类和Aysc类，从地图上的响应中绘制polyline。

下面是post 如何在Android中缓冲polyline或在polyline周围绘制多边形？的链接