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Android实现计步传感器功能

2019-10-22 18:16:01
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本文对原文:android实现计步功能初探,计步项目进行了精简,移除了进程服务和计时、守护进程、数据库保存等等,方便扩展功能。

本文源码:https://github.com/lifegh/StepOrient

Android4.4以上版本,有些手机有计步传感器可以直接使用,
而有些手机没有,但有加速度传感器,也可以实现计步功能(需要计算加速度波峰波谷来判断人走一步)!

Android,计步,传感器

一.调用

public class MainActivity extends AppCompatActivity implements StepSensorBase.StepCallBack{  .........  @Override  public void Step(int stepNum) {    // 计步回调    stepText.setText("步数:" + stepNum);  }  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);       setContentView(R.layout.activity_main);    stepText = (TextView) findViewById(R.id.step_text);    // 开启计步监听, 分为加速度传感器、或计步传感器    stepSensor = new StepSensorPedometer(this, this);    if (!stepSensor.registerStep()) {      Toast.makeText(this, "计步传传感器不可用!", Toast.LENGTH_SHORT).show();      stepSensor = new StepSensorAcceleration(this, this);      if (!stepSensor.registerStep()) {        Toast.makeText(this, "加速度传感器不可用!", Toast.LENGTH_SHORT).show();      }    }  }  ....... } /** * 计步传感器抽象类,子类分为加速度传感器、或计步传感器 */public abstract class StepSensorBase implements SensorEventListener {  private Context context;  protected StepCallBack stepCallBack;  protected SensorManager sensorManager;  protected static int CURRENT_SETP = 0;  protected boolean isAvailable = false;  public StepSensorBase(Context context, StepCallBack stepCallBack) {    this.context = context;    this.stepCallBack = stepCallBack;  }  public interface StepCallBack {    /**     * 计步回调     */    void Step(int stepNum);  }  /**   * 开启计步   */  public boolean registerStep() {    if (sensorManager != null) {      sensorManager.unregisterListener(this);      sensorManager = null;    }    sensorManager = SensorUtil.getInstance().getSensorManager(context);    registerStepListener();    return isAvailable;  }  /**   * 注册计步监听器   */  protected abstract void registerStepListener();  /**   * 注销计步监听器   */  public abstract void unregisterStep();}

二.直接使用计步传感器实现计步

/** * 计步传感器 */public class StepSensorPedometer extends StepSensorBase {  private final String TAG = "StepSensorPedometer";  private int lastStep = -1;  private int liveStep = 0;  private int increment = 0;  private int sensorMode = 0; // 计步传感器类型  public StepSensorPedometer(Context context, StepCallBack stepCallBack) {    super(context, stepCallBack);  }  @Override  protected void registerStepListener() {    Sensor detectorSensor = sensorManager.getDefaultSensor(Sensor.TYPE_STEP_DETECTOR);    Sensor countSensor = sensorManager.getDefaultSensor(Sensor.TYPE_STEP_COUNTER);    if (sensorManager.registerListener(this, detectorSensor, SensorManager.SENSOR_DELAY_GAME)) {      isAvailable = true;      sensorMode = 0;      Log.i(TAG, "计步传感器Detector可用!");    } else if (sensorManager.registerListener(this, countSensor, SensorManager.SENSOR_DELAY_GAME)) {      isAvailable = true;      sensorMode = 1;      Log.i(TAG, "计步传感器Counter可用!");    } else {      isAvailable = false;      Log.i(TAG, "计步传感器不可用!");    }  }  @Override  public void unregisterStep() {    sensorManager.unregisterListener(this);  }  @Override  public void onSensorChanged(SensorEvent event) {    liveStep = (int) event.values[0];    if (sensorMode == 0) {      Log.i(TAG, "Detector步数:"+liveStep);      StepSensorBase.CURRENT_SETP += liveStep;    } else if (sensorMode == 1) {      Log.i(TAG, "Counter步数:"+liveStep);      StepSensorBase.CURRENT_SETP = liveStep;    }    stepCallBack.Step(StepSensorBase.CURRENT_SETP);  }  @Override  public void onAccuracyChanged(Sensor sensor, int accuracy) {  }}

三.使用加速度传感器实现计步

/** * 加速度传感器 */public class StepSensorAcceleration extends StepSensorBase {  private final String TAG = "StepSensorAcceleration";  //存放三轴数据  final int valueNum = 5;  //用于存放计算阈值的波峰波谷差值  float[] tempValue = new float[valueNum];  int tempCount = 0;  //是否上升的标志位  boolean isDirectionUp = false;  //持续上升次数  int continueUpCount = 0;  //上一点的持续上升的次数,为了记录波峰的上升次数  int continueUpFormerCount = 0;  //上一点的状态,上升还是下降  boolean lastStatus = false;  //波峰值  float peakOfWave = 0;  //波谷值  float valleyOfWave = 0;  //此次波峰的时间  long timeOfThisPeak = 0;  //上次波峰的时间  long timeOfLastPeak = 0;  //当前的时间  long timeOfNow = 0;  //当前传感器的值  float gravityNew = 0;  //上次传感器的值  float gravityOld = 0;  //动态阈值需要动态的数据,这个值用于这些动态数据的阈值  final float initialValue = (float) 1.7;  //初始阈值  float ThreadValue = (float) 2.0;  //初始范围  float minValue = 11f;  float maxValue = 19.6f;  /**   * 0-准备计时  1-计时中 2-正常计步中   */  private int CountTimeState = 0;  public static int TEMP_STEP = 0;  private int lastStep = -1;  //用x、y、z轴三个维度算出的平均值  public static float average = 0;  private Timer timer;  // 倒计时3.5秒,3.5秒内不会显示计步,用于屏蔽细微波动  private long duration = 3500;  private TimeCount time;  public StepSensorAcceleration(Context context, StepCallBack stepCallBack) {    super(context, stepCallBack);  }  @Override  protected void registerStepListener() {    // 注册加速度传感器    isAvailable = sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),        SensorManager.SENSOR_DELAY_GAME);    if (isAvailable) {      Log.i(TAG, "加速度传感器可用!");    } else {      Log.i(TAG, "加速度传感器不可用!");    }  }  @Override  public void unregisterStep() {    sensorManager.unregisterListener(this);  }  public void onAccuracyChanged(Sensor arg0, int arg1) {  }  public void onSensorChanged(SensorEvent event) {    Sensor sensor = event.sensor;    synchronized (this) {      if (sensor.getType() == Sensor.TYPE_ACCELEROMETER) {        calc_step(event);      }    }  }  synchronized private void calc_step(SensorEvent event) {    average = (float) Math.sqrt(Math.pow(event.values[0], 2)        + Math.pow(event.values[1], 2) + Math.pow(event.values[2], 2));    detectorNewStep(average);  }  /*   * 检测步子,并开始计步   * 1.传入sersor中的数据   * 2.如果检测到了波峰,并且符合时间差以及阈值的条件,则判定为1步   * 3.符合时间差条件,波峰波谷差值大于initialValue,则将该差值纳入阈值的计算中   * */  public void detectorNewStep(float values) {    if (gravityOld == 0) {      gravityOld = values;    } else {      if (DetectorPeak(values, gravityOld)) {        timeOfLastPeak = timeOfThisPeak;        timeOfNow = System.currentTimeMillis();        if (timeOfNow - timeOfLastPeak >= 200            && (peakOfWave - valleyOfWave >= ThreadValue) && (timeOfNow - timeOfLastPeak) <= 2000) {          timeOfThisPeak = timeOfNow;          //更新界面的处理,不涉及到算法          preStep();        }        if (timeOfNow - timeOfLastPeak >= 200            && (peakOfWave - valleyOfWave >= initialValue)) {          timeOfThisPeak = timeOfNow;          ThreadValue = Peak_Valley_Thread(peakOfWave - valleyOfWave);        }      }    }    gravityOld = values;  }  private void preStep() {//    if (CountTimeState == 0) {//      // 开启计时器//      time = new TimeCount(duration, 700);//      time.start();//      CountTimeState = 1;//      Log.v(TAG, "开启计时器");//    } else if (CountTimeState == 1) {//      TEMP_STEP++;//      Log.v(TAG, "计步中 TEMP_STEP:" + TEMP_STEP);//    } else if (CountTimeState == 2) {    StepSensorBase.CURRENT_SETP++;//      if (stepCallBack != null) {    stepCallBack.Step(StepSensorBase.CURRENT_SETP);//      }//    }  }  /*   * 检测波峰   * 以下四个条件判断为波峰:   * 1.目前点为下降的趋势:isDirectionUp为false   * 2.之前的点为上升的趋势:lastStatus为true   * 3.到波峰为止,持续上升大于等于2次   * 4.波峰值大于1.2g,小于2g   * 记录波谷值   * 1.观察波形图,可以发现在出现步子的地方,波谷的下一个就是波峰,有比较明显的特征以及差值   * 2.所以要记录每次的波谷值,为了和下次的波峰做对比   * */  public boolean DetectorPeak(float newValue, float oldValue) {    lastStatus = isDirectionUp;    if (newValue >= oldValue) {      isDirectionUp = true;      continueUpCount++;    } else {      continueUpFormerCount = continueUpCount;      continueUpCount = 0;      isDirectionUp = false;    }//    Log.v(TAG, "oldValue:" + oldValue);    if (!isDirectionUp && lastStatus        && (continueUpFormerCount >= 2 && (oldValue >= minValue && oldValue < maxValue))) {      peakOfWave = oldValue;      return true;    } else if (!lastStatus && isDirectionUp) {      valleyOfWave = oldValue;      return false;    } else {      return false;    }  }  /*   * 阈值的计算   * 1.通过波峰波谷的差值计算阈值   * 2.记录4个值,存入tempValue[]数组中   * 3.在将数组传入函数averageValue中计算阈值   * */  public float Peak_Valley_Thread(float value) {    float tempThread = ThreadValue;    if (tempCount < valueNum) {      tempValue[tempCount] = value;      tempCount++;    } else {      tempThread = averageValue(tempValue, valueNum);      for (int i = 1; i < valueNum; i++) {        tempValue[i - 1] = tempValue[i];      }      tempValue[valueNum - 1] = value;    }    return tempThread;  }  /*   * 梯度化阈值   * 1.计算数组的均值   * 2.通过均值将阈值梯度化在一个范围里   * */  public float averageValue(float value[], int n) {    float ave = 0;    for (int i = 0; i < n; i++) {      ave += value[i];    }    ave = ave / valueNum;    if (ave >= 8) {//      Log.v(TAG, "超过8");      ave = (float) 4.3;    } else if (ave >= 7 && ave < 8) {//      Log.v(TAG, "7-8");      ave = (float) 3.3;    } else if (ave >= 4 && ave < 7) {//      Log.v(TAG, "4-7");      ave = (float) 2.3;    } else if (ave >= 3 && ave < 4) {//      Log.v(TAG, "3-4");      ave = (float) 2.0;    } else {//      Log.v(TAG, "else");      ave = (float) 1.7;    }    return ave;  }  class TimeCount extends CountDownTimer {    public TimeCount(long millisInFuture, long countDownInterval) {      super(millisInFuture, countDownInterval);    }    @Override    public void onFinish() {      // 如果计时器正常结束,则开始计步      time.cancel();      StepSensorBase.CURRENT_SETP += TEMP_STEP;      lastStep = -1;      Log.v(TAG, "计时正常结束");      timer = new Timer(true);      TimerTask task = new TimerTask() {        public void run() {          if (lastStep == StepSensorBase.CURRENT_SETP) {            timer.cancel();            CountTimeState = 0;            lastStep = -1;            TEMP_STEP = 0;            Log.v(TAG, "停止计步:" + StepSensorBase.CURRENT_SETP);          } else {            lastStep = StepSensorBase.CURRENT_SETP;          }        }      };      timer.schedule(task, 0, 2000);      CountTimeState = 2;    }    @Override    public void onTick(long millisUntilFinished) {      if (lastStep == TEMP_STEP) {        Log.v(TAG, "onTick 计时停止:" + TEMP_STEP);        time.cancel();        CountTimeState = 0;        lastStep = -1;        TEMP_STEP = 0;      } else {        lastStep = TEMP_STEP;      }    }  }}

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