为什么我无法从我的路线 api 请求中获得概览折线

Question

我正在尝试以 Xamarin 形式在我的地图上绘制包含 waypoints 的多段线。现在，我向 Google 方向 API

发送以下请求

https://maps.googleapis.com/maps/api/directions/json?mode=driving&transit_routing_preference=less_driving&origin=31 Clairwood Rd, Harare, Zimbabwe&destination=8 Joshua Nkomo St, Bulawayo, Zimbabwe&waypoints=via:No. 1 Railway Ave, R Mugabe Hwy, Kwekwe, Zimbabwe|via:55 Fifth St, Gweru, Zimbabwe|via:Shangani Rd, Harare, Zimbabwe|via:XVJX+62J, Chivhu, Zimbabwe&key=KEY

我收到以下回复

{
    "geocoded_waypoints": [
        {
            "geocoder_status": "OK",
            "place_id": "EiEzMSBDbGFpcndvb2QgUmQsIEhhcmFyZSwgWmltYmFid2UiGhIYChQKEgmBVmGqRqUxGRFK3dLcshV1ExAf",
            "types": [
                "street_address"
            ]
        },
        {
            "geocoder_status": "OK",
            "partial_match": true,
            "place_id": "ChIJIf-owoJpNBkR4od3cGjZYCs",
            "types": [
                "establishment",
                "point_of_interest",
                "university"
            ]
        },
        {
            "geocoder_status": "OK",
            "place_id": "ChIJ5TwQo5mUNBkRNhE_iYH5nXU",
            "types": [
                "street_address"
            ]
        },
        {
            "geocoder_status": "OK",
            "place_id": "EiU4IEpvc2h1YSBOa29tbyBTdCwgQnVsYXdheW8sIFppbWJhYndlIhoSGAoUChIJcXSTo35UtR4RIh0xgqF3-AwQCA",
            "types": [
                "street_address"
            ]
        }
    ],
    "routes": [],
    "status": "ZERO_RESULTS"
}

但是，当我发送这个

https://maps.googleapis.com/maps/api/directions/json?origin=31 Clairwood Rd, Harare, Zimbabwe&destination=8 Joshua Nkomo St, Bulawayo, Zimbabwe&waypoints=via: Gweru Polytechnic, Gweru|via: M.S.U. Zvishavane Campus, Zvishavane&key=KEY

我得到了好评。

现在，我不确定为什么第一个请求没有得到任何结果响应，有人可以帮助我解释为什么。我研究研究了，似乎找不到合适的答案。

Answer 1

我想我没有优化我的路线。发送请求的正确方式应该是：

https://maps.googleapis.com/maps/api/directions/json?mode=driving&transit_routing_preference=less_driving&origin=31 Clairwood Rd, Harare, Zimbabwe&destination=8 Joshua Nkomo St, Bulawayo, Zimbabwe&waypoints=optimize:true|No. 1 Railway Ave, R Mugabe Hwy, Kwekwe, Zimbabwe|55 Fifth St, Gweru, Zimbabwe|Shangani Rd, Harare, Zimbabwe|XVJX+62J, Chivhu, Zimbabwe&key=KEY
``

为什么我无法从我的路线 api 请求中获得概览折线

Why can't I get an overview polyline from my directions api request

google-maps

google-directions-api