腾讯位置服务GPS轨迹录制-安卓篇
前言 在地图的使用中，尤其在导航场景下，进行GPS轨迹录制是十分必要并且有用的，本文会对于安卓系统下的轨迹录制部分做一个分享。 系统架构 对于一个GPSRecordSystem（GPS轨迹录制系统）主要分成3个部分：开始录制，录制GPS定位，结束录制并存储，如上图右方所示。在实际应用中，以导航系统为例：（1）在开始导航时（start navi）,进行录制工作的相关配置；（2）收到安卓系统的onLocationChanged的callback进行GPSLocation的记录；（3）结束导航（stop navi）时，停止记录并存入文件。 相关代码展示 用到的相关变量 private LocationManager mLocationManager; // 系统locationManager private LocationListener mLocationListener; // 系统locationListener private boolean mIsRecording = false; // 是否正在录制 private List<String> mGpsList; // 记录gps的list private String mRecordFileName; // gps文件名称 开始录制 开始录制一般是在整个系统工作之初，比如在导航场景下，当“开始导航”时，可以开始进行“startRecordLocation” 的配置 public void startRecordLocation(Context context, String fileName) { // 已经在录制中不进行录制 if (mIsRecording) { return; } Toast.makeText(context, "start record location...", Toast.LENGTH_SHORT).show(); // 初始化locationManager和locationListener mLocationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); mLocationListener = new MyLocationListener(); try { // 添加listener mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mLocationListener); } catch (SecurityException e) { Toast.makeText(context, "start record location error!!!", Toast.LENGTH_SHORT).show(); Log.e(TAG, "startRecordLocation Exception", e); e.printStackTrace(); } // 记录文件名称，笔者这里使用“realLocationRecord + routeID”形式进行记录 mRecordFileName = fileName; if (!mRecordFileName.endsWith(".gps")) { mRecordFileName += ".gps"; } mIsRecording = true; } 录制中记录轨迹 记录location一般是在获取安卓系统onLocationChanged回调时调用“recordGPSLocation” public void recordGPSLocation(Location location) { if (mIsRecording && location != null) { // 记录location to list mGpsList.add(locationToString(location)); } } locationToString工具方法 驱动导航工作的GPS轨迹点一般要包含以下几个要素，经度，纬度，精度，角度，速度，时间，海拔高度，所以在此记录下，为后期轨迹回放做准备。 private String locationToString(Location location) { StringBuilder sb = new StringBuilder(); long time = System.currentTimeMillis(); String timeStr = gpsDataFormatter.format(new Date(time)); sb.append(location.getLatitude()); sb.append(","); sb.append(location.getLongitude()); sb.append(","); sb.append(location.getAccuracy()); sb.append(","); sb.append(location.getBearing()); sb.append(","); sb.append(location.getSpeed()); sb.append(","); sb.append(timeStr); sb.append(","); sb.append(df.format((double) time / 1000.0)); // sb.append(df.format(System.currentTimeMillis()/1000.0)); // sb.append(df.format(location.getTime()/1000.0)); sb.append(","); sb.append(location.getAltitude()); sb.append("\n"); return sb.toString(); } 结束录制并保存gps文件 结束录制一般作用在整个系统的结尾，例如在导航场景下，“结束导航”时停止录制调用“stopRecordLocation” public void stopRecordLocation(Context context) { Toast.makeText(context, "stop record location, save to file...", Toast.LENGTH_SHORT).show(); // 移除listener mLocationManager.removeUpdates(mLocationListener); String storagePath = StorageUtil.getStoragePath(context); // 存储的路径 String filePath = storagePath + mRecordFileName; saveGPS(filePath); mIsRecording = false; } GPS轨迹存储工具方法 private void saveGPS(String path) { OutputStreamWriter writer = null; try { File outFile = new File(path); File parent = outFile.getParentFile(); if (parent != null && !parent.exists()) { parent.mkdirs(); } OutputStream out = new FileOutputStream(outFile); writer = new OutputStreamWriter(out); for (String line : mGpsList) { writer.write(line); } } catch (Exception e) { Log.e(TAG, "saveGPS Exception", e); e.printStackTrace(); } finally { if (writer != null) { try { writer.flush(); } catch (IOException e) { e.printStackTrace(); Log.e(TAG, "Failed to flush output stream", e); } try { writer.close(); } catch (IOException e) { e.printStackTrace(); Log.e(TAG, "Failed to close output stream", e); } } } } StorageUtil的getStoragePath工具方法 // 存储在跟路径下/TencentMapSDK/navigation private static final String NAVIGATION_PATH = "/tencentmapsdk/navigation"; // getStoragePath工具方法 public static String getStoragePath(Context context) { if (context == null) { return null; } String strFolder; boolean hasSdcard; try { hasSdcard = Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED); } catch (Exception e) { Log.e(TAG, "getStoragePath Exception", e); e.printStackTrace(); hasSdcard = false; } if (!hasSdcard) { strFolder = context.getFilesDir().getPath() + NAVIGATION_PATH; File file = new File(strFolder); if (!file.exists()) { file.mkdirs(); } } else { strFolder = Environment.getExternalStorageDirectory().getPath() + NAVIGATION_PATH; File file = new File(strFolder); if (!file.exists()) { // 目录不存在，创建目录 if (!file.mkdirs()) { strFolder = context.getFilesDir().getPath() + NAVIGATION_PATH; file = new File(strFolder); if (!file.exists()) { file.mkdirs(); } } } else { // 目录存在，创建文件测试是否有权限 try { String newFile = strFolder + "/.test"; File tmpFile = new File(newFile); if (tmpFile.createNewFile()) { tmpFile.delete(); } } catch (IOException e) { e.printStackTrace(); Log.e(TAG, "getStoragePath Exception", e); strFolder = context.getFilesDir().getPath() + NAVIGATION_PATH; file = new File(strFolder); if (!file.exists()) { file.mkdirs(); } } } } return strFolder; } 结果展示 最终存储在了手机目录下的navigation目录 后续工作 后续可以对于录制的gps文件讲解在导航场景下进行轨迹回放的分享
