网上比较流行的计步好多都是用第一中方法写，是一套算法：
下边是第一种的代码，个人感觉准确度不是很好，，误差经常在好几十往上，但是也还能用：下载地址：
package com.example.pedometerdemo;import java.util.List;import java.util.Timer;import android.app.ActivityManager;import android.app.ActivityManager.RunningTaskInfo;import android.app.Service;import android.content.Context;import android.content.Intent;import android.hardware.Sensor;import android.hardware.SensorEvent;import android.hardware.SensorEventListener;import android.hardware.SensorManager;import android.os.IBinder;import android.util.Log;public class pedometerService extends Service implements SensorEventListener { public static final String STEP_CHANGE = "step_change"; public static final String ADD_STEPS = "add_Step"; private static final int notifiId = 11; private Intent intent; private ActivityManager activityManager; private SensorManager sensorManager; private Timer timer = new Timer(); private long lastTime;// 上次记步的时间 private float mLimit = 6.44f; private int interval_time; private float mLastValues[] = new float[3 * 2]; private float mScale[] = new float[2]; private float mYOffset; private float mLastDirections[] = new float[3 * 2]; private float mLastExtremes[][] = { new float[3 * 2], new float[3 * 2] }; private float mLastDiff[] = new float[3 * 2]; private int mLastMatch = -1; private int startStep; private Service instance; private float[] xyz=new float[3]; @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null; } @Override public void onCreate() { // TODO Auto-generated method stub super.onCreate(); instance = this; initData(); initStepDetector(); interval_time = 200; } @Override public int onStartCommand(Intent intent, int flags, int startId) { // TODO Auto-generated method stub System.out.println("启动"); return START_REDELIVER_INTENT; } @Override public void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); sensorManager.unregisterListener(this); } @Override public void onSensorChanged(SensorEvent event) { // TODO Auto-generated method stub Sensor sensor = event.sensor; synchronized (this) { if (System.currentTimeMillis() – lastTime < interval_time) { return; } if (sensor.getType() == Sensor.TYPE_ORIENTATION) { } else { int j = (sensor.getType() == Sensor.TYPE_ACCELEROMETER) ? 1 : 0; if (j == 1) { float vSum = 0; for (int i = 0; i < 3; i++) { final float v = mYOffset + event.values[i] * mScale[j]; vSum += v; } int k = 0; float v = vSum / 3; float direction = (v > mLastValues[k] ? 1 : (v < mLastValues[k] ? -1 : 0)); if (direction == -mLastDirections[k]) { // Direction changed int extType = (direction > 0 ? 0 : 1); // minumum or // maximum? mLastExtremes[extType][k] = mLastValues[k]; float diff = Math.abs(mLastExtremes[extType][k] – mLastExtremes[1 – extType][k]); if (diff > mLimit) { boolean isAlmostAsLargeAsPrevious = diff > (mLastDiff[k] * 2 / 3); boolean isPreviousLargeEnough = mLastDiff[k] > (diff / 3); boolean isNotContra = (mLastMatch != 1 – extType); if (isAlmostAsLargeAsPrevious && isPreviousLargeEnough && isNotContra) { long currentTime = System.currentTimeMillis(); if (currentTime – lastTime > 2000) { startStep = 0; } else { Log.e("STEP", startStep+++""); } mLastMatch = extType; lastTime = currentTime; } else { mLastMatch = -1; } } mLastDiff[k] = diff; } mLastDirections[k] = direction; mLastValues[k] = v; } } } } private boolean appIsTop() { if (activityManager == null) { activityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE); } List<RunningTaskInfo> rti = activityManager.getRunningTasks(1); String packagename = rti.get(0).topActivity.getPackageName(); if (packagename.equals(getPackageName())) { return true; } return false; } public void initStepDetector() { int h = 480; // TODO: remove this constant mYOffset = h * 0.5f; mScale[0] = -(h * 0.5f * (1.0f / (SensorManager.STANDARD_GRAVITY * 2))); mScale[1] = -(h * 0.5f * (1.0f / (SensorManager.MAGNETIC_FIELD_EARTH_MAX))); } @Override public void onAccuracyChanged(Sensor arg0, int arg1) { // TODO Auto-generated method stub } private void initData() { sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE); if (sensorManager != null) {// 注册监听器 sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_FASTEST); // 第一个参数是Listener，第二个参数是所得传感器类型，第三个参数值获取传感器信息的频率 } } }
还有第二种，我觉得是误差小点的，自己测试了下，不管别的情况的，就是正常走路的误差在10步左右：看看代码，他是封成了好几个方法，上最主要的逻辑代码：
下载地址：
每天告诉自己一次，『我真的很不错』
