需求 有个表单需要一键获取对应位置 并显示出来效果如下：

点击一键获取获取对应位置 显示在  picker 默认选中

前端  代码如下:

     <view class="box_7  {{ showChange==1? 'change-style':'' }}">
          <view class="box_11">
            <view class="text-wrapper_6 {{ showChange==1? 'change-style-postiona':'' }}">
              <text lines="1" class="text_29">考试地址</text>
              <text lines="1" class="text_30" />
              <text lines="1" class="text_31">*</text>
            </view>
                <picker class="region-select" mode="region" bindchange="bindRegionChange" value="{{region}}" custom-item="{{customItem}}">
                <view class="picker">
                {{region[0]}}   {{region[1]}}     {{region[2]}}
                </view>
              </picker>
              <button  bindtap="getUserLocation" class="get-position {{ showChange==1? 'change-style-postion':''}}">一键获取</button>
          </view>
        </view>

一定注意：小程序中要配置，不然获取位置不生效。

  "permission": {
    "scope.userLocation": {
      "desc": "你的位置信息将用于小程序位置接口的效果展示"
     }
 },
 "requiredPrivateInfos" : [ "getLocation" ],

小程序js如下：注意 获取到 经纬度之后 请求腾讯 api key 要进行申请 ，申请很快

申请地址 腾讯位置服务 - 立足生态，连接未来

getUserLocation: function () {
  let that = this;
  wx.getSetting({
    success: (res) => {
      if (res.authSetting['scope.userLocation'] != undefined && res.authSetting['scope.userLocation'] != true) 
      {//如果没有授权就提示需要授权
        wx.showModal({
          title: '请求授权当前位置',
          content: '需要获取您的地理位置，请确认授权',
          success: function (res) {
            if (res.cancel) {
              wx.showToast({
                title: '拒绝授权',
                icon: 'none',
                duration: 1000
              })
            } else if (res.confirm) {
              wx.openSetting({
                success: function (dataAu) {
                  if (dataAu.authSetting["scope.userLocation"] == true) {
                    wx.showToast({
                      title: '授权成功',
                      icon: 'success',
                      duration: 1000
                    })
                    //再次授权，调用wx.getLocation的API
                    that.getLocations();
                  } else {
                    wx.showToast({
                      title: '授权失败',
                      icon: 'none',
                      duration: 1000
                    })
                  }
                }
              })
            }
          }
        })
      } else if (res.authSetting['scope.userLocation'] == undefined) {
        that.getLocations();
      }
      else {
      
        that.getLocations();
      }
    }
  })
},
//获取经纬度

getLocations()
{
  let that = this;
  wx.getLocation({
    type: 'wgs84',
    success (res) {
    
      const latitude = res.latitude
      const longitude = res.longitude
      wx.request({
        url: 'https://apis.map.qq.com/ws/geocoder/v1/',
        data: {
          location: `${latitude},${longitude}`,
          key: that.data.key,
          get_poi: 0
        },
        success(res) {
          if(res.statusCode==200){
            const addressComponent = res.data.result.address_component;
            const province = addressComponent.province;
            const city = addressComponent.city;
            const district = addressComponent.district;
            var showChange =0;
            if((province+city+district).length>=12){
              showChange =1;
           }
           var result = [province, city, district];
           that.setData({
             region: result,
             showChange: showChange,
             addressSelect:1,
           })
          }else{
            wx.showToast({
              title: '定位获取失败,请手动选择~',
              icon: 'none'
            })
          }
         
        }
      })

      
    }
   })
},