文章目的

專案開發所需，所以結合百度地圖提供的小車平滑軌跡移動，自己寫的demo

實現效果

程式碼下載

下載連結

下面是實現的關鍵步驟

整合百度地圖

怎麼整合自然是看百度地圖開發平臺提供的文件。

文件連線

規劃線路

看百度地圖的文件，寫一個規劃線路的工具類（駕車的）

package com.wzhx.car_smooth_move_demo.utils;
import android.util.Log;
import com.baidu.mapapi.search.route.BikingRouteResult;
import com.baidu.mapapi.search.route.DrivingRoutePlanOption;
import com.baidu.mapapi.search.route.DrivingRouteResult;
import com.baidu.mapapi.search.route.IndoorRouteResult;
import com.baidu.mapapi.search.route.MassTransitRouteResult;
import com.baidu.mapapi.search.route.OnGetRoutePlanResultListener;
import com.baidu.mapapi.search.route.PlanNode;
import com.baidu.mapapi.search.route.RoutePlanSearch;
import com.baidu.mapapi.search.route.TransitRouteResult;
import com.baidu.mapapi.search.route.WalkingRouteResult;
import com.wzhx.car_smooth_move_demo.listener.OnGetDrivingResultListener;
public class RoutePlanUtil {
  private RoutePlanSearch mRoutePlanSearch = RoutePlanSearch.newInstance();
  private OnGetDrivingResultListener getDrivingResultListener;
  private OnGetRoutePlanResultListener getRoutePlanResultListener = new OnGetRoutePlanResultListener() {
    @Override
    public void onGetWalkingRouteResult(WalkingRouteResult walkingRouteResult) {
    }
    @Override
    public void onGetTransitRouteResult(TransitRouteResult transitRouteResult) {
    }
    @Override
    public void onGetMassTransitRouteResult(MassTransitRouteResult massTransitRouteResult) {
    }
    @Override
    public void onGetDrivingRouteResult(DrivingRouteResult drivingRouteResult) {
      Log.e("測試",drivingRouteResult.error + ":" + drivingRouteResult.status);
      getDrivingResultListener.onSuccess(drivingRouteResult);
    }
    @Override
    public void onGetIndoorRouteResult(IndoorRouteResult indoorRouteResult) {
    }
    @Override
    public void onGetBikingRouteResult(BikingRouteResult bikingRouteResult) {
    }
  };
  public RoutePlanUtil(OnGetDrivingResultListener getDrivingResultListener) {
    this.getDrivingResultListener = getDrivingResultListener;
    this.mRoutePlanSearch.setOnGetRoutePlanResultListener(this.getRoutePlanResultListener);
  }
  public void routePlan(PlanNode startNode,PlanNode endNode){
    mRoutePlanSearch.drivingSearch((new DrivingRoutePlanOption())
        .from(startNode).to(endNode)
        .policy(DrivingRoutePlanOption.DrivingPolicy.ECAR_TIME_FIRST)
        .trafficPolicy(DrivingRoutePlanOption.DrivingTrafficPolicy.ROUTE_PATH_AND_TRAFFIC));
  }
}

規劃線路後需要將實時路況索引儲存，為後面畫圖需要

// 設定路段實時路況索引
        List<DrivingRouteLine.DrivingStep> allStep = selectedRouteLine.getAllStep();
        mTrafficTextureIndexList.clear();
        for (int j = 0; j < allStep.size(); j++) {
          if (allStep.get(j).getTrafficList() != null && allStep.get(j).getTrafficList().length > 0) {
            for (int k = 0; k < allStep.get(j).getTrafficList().length; k++) {
              mTrafficTextureIndexList.add(allStep.get(j).getTrafficList()[k]);
            }
          }
        }

要將路線規劃的路線上的路段再細分（切割），這樣小車移動才會平滑

/**
   * 將規劃好的路線點進行擷取
   * 參考百度給的小車平滑軌跡移動demo實現。（迴圈的演算法不太懂）
   * @param routeLine
   * @param distance
   * @return
   */
  private ArrayList<LatLng> divideRouteLine(ArrayList<LatLng> routeLine,double distance) {
    // 擷取後的路線點的結果集
    ArrayList<LatLng> result = new ArrayList<>();
    mNewTrafficTextureIndexList.clear();
    for (int i = 0; i < routeLine.size() - 1; i++) {
      final LatLng startPoint = routeLine.get(i);
      final LatLng endPoint = routeLine.get(i + 1);
      double slope = getSlope(startPoint,endPoint);
      // 是不是正向的標示
      boolean isYReverse = (startPoint.latitude > endPoint.latitude);
      boolean isXReverse = (startPoint.longitude > endPoint.longitude);
      double intercept = getInterception(slope,startPoint);
      double xMoveDistance = isXReverse ? getXMoveDistance(slope,distance) :
          -1 * getXMoveDistance(slope,distance);
      double yMoveDistance = isYReverse ? getYMoveDistance(slope,distance) :
          -1 * getYMoveDistance(slope,distance);
      ArrayList<LatLng> temp1 = new ArrayList<>();
      for (double j = startPoint.latitude,k = startPoint.longitude;
         !((j > endPoint.latitude) ^ isYReverse) && !((k > endPoint.longitude) ^ isXReverse); ) {
        LatLng latLng = null;
        if (slope == Double.MAX_VALUE) {
          latLng = new LatLng(j,k);
          j = j - yMoveDistance;
        } else if (slope == 0.0) {
          latLng = new LatLng(j,k - xMoveDistance);
          k = k - xMoveDistance;
        } else {
          latLng = new LatLng(j,(j - intercept) / slope);
          j = j - yMoveDistance;
        }
        final LatLng finalLatLng = latLng;
        if (finalLatLng.latitude == 0 && finalLatLng.longitude == 0) {
          continue;
        }
        mNewTrafficTextureIndexList.add(mTrafficTextureIndexList.get(i));
        temp1.add(finalLatLng);
      }
      result.addAll(temp1);
      if (i == routeLine.size() - 2) {
        result.add(endPoint); // 終點
      }
    }
    return result;
  }

最後是開啟子執行緒，對小車狀態進行更新（車頭方向和小車位置）

/**
   * 迴圈進行移動邏輯
   */
  public void moveLooper() {
    moveThread = new Thread() {
      public void run() {
        Thread thisThread = Thread.currentThread();
        while (!exit) {
          for (int i = 0; i < latLngs.size() - 1; ) {
            if (exit) {
              break;
            }
            for (int p = 0; p < latLngs.size() - 1; p++) {
              // 這是更新索引的條件，這裡總是為true
              // 實際情況可以是：當前誤差小於5米 DistanceUtil.getDistance(mCurrentLatLng,latLngs.get(p)) <= 5）
              // mCurrentLatLng 這個小車的當前位置得自行獲取得到
              if (true) {
//               實際情況的索引更新 mIndex = p;
                mIndex++; // 模擬就是每次加1
                runOnUiThread(new Runnable() {
                  @Override
                  public void run() {
                    Toast.makeText(mContext,"當前索引：" + mIndex,Toast.LENGTH_SHORT).show();
                  }
                });
                break;
              }
            }

            // 改變迴圈條件
            i = mIndex + 1;

            if (mIndex >= latLngs.size() - 1) {
              exit = true;
              break;
            }

            // 擦除走過的路線
            int len = mNewTrafficTextureIndexList.subList(mIndex,mNewTrafficTextureIndexList.size()).size();
            Integer[] integers = mNewTrafficTextureIndexList.subList(mIndex,mNewTrafficTextureIndexList.size()).toArray(new Integer[len]);
            int[] index = new int[integers.length];
            for (int x = 0; x < integers.length; x++) {
              index[x] = integers[x];
            }
            if (index.length > 0) {
              mPolyline.setIndexs(index);
              mPolyline.setPoints(latLngs.subList(mIndex,latLngs.size()));
            }

            // 這裡是小車的當前點和下一個點，用於確定車頭方向
            final LatLng startPoint = latLngs.get(mIndex);
            final LatLng endPoint = latLngs.get(mIndex + 1);

            mHandler.post(new Runnable() {
              @Override
              public void run() {
                // 更新小車的位置和車頭的角度
                if (mMapView == null) {
                  return;
                }
                mMoveMarker.setPosition(startPoint);
                mMoveMarker.setRotate((float) getAngle(startPoint,endPoint));
              }
            });

            try {
              // 控制執行緒更新時間間隔
              thisThread.sleep(TIME_INTERVAL);
            } catch (InterruptedException e) {
              e.printStackTrace();
            }
          }
        }
      }
    };
    // 啟動執行緒
    moveThread.start();
  }