让 Deepseek GPS测速

下面是一个简单的微信小程序GPS测速功能的实现代码，包括前端页面和后端逻辑。

1. 页面结构 (index.wxml)

<view class="container">
  <view class="speed-display">
    <text class="speed-value">{{speed}}</text>
    <text class="speed-unit">km/h</text>
  </view>
  
  <view class="info-section">
    <view class="info-item">
      <text>经度:</text>
      <text>{{longitude}}</text>
    </view>
    <view class="info-item">
      <text>纬度:</text>
      <text>{{latitude}}</text>
    </view>
    <view class="info-item">
      <text>精度:</text>
      <text>{{accuracy}}米</text>
    </view>
  </view>
  
  <button bindtap="startGPS" type="primary" disabled="{{isRunning}}">开始测速</button>
  <button bindtap="stopGPS" type="warn" disabled="{{!isRunning}}">停止测速</button>
</view>

2. 页面样式 (index.wxss)

.container {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 20px;
}

.speed-display {
  display: flex;
  align-items: baseline;
  margin: 40px 0;
}

.speed-value {
  font-size: 60px;
  font-weight: bold;
}

.speed-unit {
  font-size: 20px;
  margin-left: 5px;
}

.info-section {
  width: 100%;
  margin: 30px 0;
}

.info-item {
  display: flex;
  justify-content: space-between;
  margin: 10px 0;
  padding: 10px;
  background-color: #f5f5f5;
  border-radius: 5px;
}

button {
  width: 80%;
  margin: 10px 0;
}

3. 页面逻辑 (index.js)

Page({
  data: {
    speed: '0.00',
    longitude: '--',
    latitude: '--',
    accuracy: '--',
    isRunning: false,
    gpsWatchId: null,
    lastPosition: null,
    lastUpdateTime: null
  },

  startGPS: function() {
    const that = this;
    
    // 检查是否已经授权
    wx.getSetting({
      success(res) {
        if (!res.authSetting['scope.userLocation']) {
          // 未授权，请求授权
          wx.authorize({
            scope: 'scope.userLocation',
            success() {
              that._startWatching();
            },
            fail() {
              wx.showToast({
                title: '需要位置权限',
                icon: 'none'
              });
            }
          });
        } else {
          // 已授权，开始监听
          that._startWatching();
        }
      }
    });
  },

  _startWatching: function() {
    const that = this;
    
    this.setData({
      isRunning: true,
      speed: '0.00'
    });
    
    // 开始监听位置变化
    const watchId = wx.startLocationUpdate({
      type: 'gcj02',
      success: () => {
        wx.onLocationChange(function(res) {
          that._updatePosition(res);
        });
      },
      fail(err) {
        console.error('启动位置监听失败', err);
        wx.showToast({
          title: '启动失败',
          icon: 'none'
        });
        that.setData({ isRunning: false });
      }
    });
    
    this.setData({ gpsWatchId: watchId });
  },

  _updatePosition: function(position) {
    const now = Date.now();
    let speed = 0;
    
    if (this.data.lastPosition && this.data.lastUpdateTime) {
      // 计算距离（米）
      const distance = this._calculateDistance(
        this.data.lastPosition.latitude, 
        this.data.lastPosition.longitude,
        position.latitude,
        position.longitude
      );
      
      // 计算时间差（小时）
      const timeDiff = (now - this.data.lastUpdateTime) / 1000 / 3600;
      
      // 计算速度（公里/小时）
      if (timeDiff > 0) {
        speed = distance / 1000 / timeDiff;
      }
    }
    
    this.setData({
      speed: speed.toFixed(2),
      longitude: position.longitude.toFixed(6),
      latitude: position.latitude.toFixed(6),
      accuracy: position.accuracy.toFixed(0),
      lastPosition: position,
      lastUpdateTime: now
    });
  },

  // 计算两个坐标点之间的距离（米）
  _calculateDistance: function(lat1, lon1, lat2, lon2) {
    const R = 6371000; // 地球半径，单位米
    const dLat = (lat2 - lat1) * Math.PI / 180;
    const dLon = (lon2 - lon1) * Math.PI / 180;
    const a = 
      Math.sin(dLat/2) * Math.sin(dLat/2) +
      Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) * 
      Math.sin(dLon/2) * Math.sin(dLon/2);
    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    return R * c;
  },

  stopGPS: function() {
    if (this.data.gpsWatchId) {
      wx.stopLocationUpdate({
        success: () => {
          wx.offLocationChange();
          this.setData({ 
            isRunning: false,
            gpsWatchId: null
          });
        },
        fail(err) {
          console.error('停止位置监听失败', err);
        }
      });
    }
  },

  onUnload: function() {
    // 页面卸载时停止监听
    this.stopGPS();
  }
});

4. 配置文件 (app.json)

确保在app.json中声明了位置权限：

{
  "pages": [
    "pages/index/index"
  ],
  "permission": {
    "scope.userLocation": {
      "desc": "你的位置信息将用于测速功能"
    }
  },
  "requiredPrivateInfos": ["getLocation", "onLocationChange", "startLocationUpdate"]
}