android手机计步器功能

在市面上浏览过众多的计步软件，可惜没有开源的代码，而github上的几个开源的计步代码，要么就是记得不准，要么就是功能不完善，不稳定，于是决心自己写一个，分享给大家使用，希望大家一起来完善。

已上传github：https://github.com/xfmax/BasePedo

流程图：

核心代码如下：

package com.base.basepedo.service;    import android.content.Context;  import android.hardware.Sensor;  import android.hardware.SensorEvent;  import android.hardware.SensorEventListener;  import android.util.Log;    import com.base.basepedo.utils.CountDownTimer;    import java.util.Timer;  import java.util.TimerTask;    public class StepDcretor implements SensorEventListener {      private final String TAG = "StepDcretor";      // alpha 由 t / (t + dT)计算得来，其中 t 是低通滤波器的时间常数，dT 是事件报送频率      private final float alpha = 0.8f;      private long perCalTime = 0;      private final float minValue = 8.8f;      private final float maxValue = 10.5f;      private final float verminValue = 9.5f;      private final float vermaxValue = 10.0f;      private final float minTime = 150;      private final float maxTime = 2000;      /**       * 0-准备计时   1-计时中  2-准备为正常计步计时  3-正常计步中       */      private int CountTimeState = 0;      public static int CURRENT_SETP = 0;      public static int TEMP_STEP = 0;      private int lastStep = -1;      // 加速计的三个维度数值      public static float[] gravity = new float[3];      public static float[] linear_acceleration = new float[3];      //用三个维度算出的平均值      public static float average = 0;        private Timer timer;      // 倒计时8秒，8秒内不会显示计步，用于屏蔽细微波动      private long duration = 8000;      private TimeCount time;        OnSensorChangeListener onSensorChangeListener;        public StepDcretor(Context context) {          super();      }        public void onSensorChanged(SensorEvent event) {          Sensor sensor = event.sensor;          synchronized (this) {              if (sensor.getType() == Sensor.TYPE_ACCELEROMETER) {                    // 用低通滤波器分离出重力加速度                  gravity[0] = alpha * gravity[0] + (1 - alpha) * event.values[0];                  gravity[1] = alpha * gravity[1] + (1 - alpha) * event.values[1];                  gravity[2] = alpha * gravity[2] + (1 - alpha) * event.values[2];                    average = (float) Math.sqrt(Math.pow(gravity[0], 2)                          + Math.pow(gravity[1], 2) + Math.pow(gravity[2], 2));                    if (average <= verminValue) {                      if (average <= minValue) {                          perCalTime = System.currentTimeMillis();                      }                  } else if (average >= vermaxValue) {                      if (average >= maxValue) {                          float betweentime = System.currentTimeMillis()                                  - perCalTime;                          if (betweentime >= minTime && betweentime < maxTime) {                              perCalTime = 0;                              if (CountTimeState == 0) {                                  // 开启计时器                                  time = new TimeCount(duration, 1000);                                  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) {                                  timer = new Timer(true);                                  TimerTask task = new TimerTask() {                                      public void run() {                                          if (lastStep == CURRENT_SETP) {                                              timer.cancel();                                              CountTimeState = 0;                                              lastStep = -1;                                              TEMP_STEP = 0;                                              Log.v(TAG, "停止计步：" + CURRENT_SETP);                                          } else {                                              lastStep = CURRENT_SETP;                                          }                                      }                                  };                                  timer.schedule(task, 0, 2000);                                  CountTimeState = 3;                              } else if (CountTimeState == 3) {                                  CURRENT_SETP++;                              }                          }                      }                  }                    if (onSensorChangeListener != null) {                      onSensorChangeListener.onChange();                  }              }          }      }          public void onAccuracyChanged(Sensor arg0, int arg1) {        }        public interface OnSensorChangeListener {          void onChange();      }        public OnSensorChangeListener getOnSensorChangeListener() {          return onSensorChangeListener;      }        public void setOnSensorChangeListener(              OnSensorChangeListener onSensorChangeListener) {          this.onSensorChangeListener = onSensorChangeListener;      }        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();              CURRENT_SETP += TEMP_STEP;              lastStep = -1;              CountTimeState = 2;              Log.v(TAG, "计时正常结束");          }            @Override          public void onTick(long millisUntilFinished) {              if (lastStep == TEMP_STEP) {                  Log.v(TAG, "onTick 计时停止");                  time.cancel();                  CountTimeState = 0;                  lastStep = -1;                  TEMP_STEP = 0;              } else {                  lastStep = TEMP_STEP;              }          }        }  }

来自： http://blog.csdn.net/xf396191344/article/details/50467570