我想计算android手机用户的步数(基本上我想实现一个基本的计步器)。我使用的逻辑是,如果 z 方向上的加速度变化大于某个阈值,则必须将其计为一步。
我的应用程序使用以下代码使用加速度计来计算所采取的步数
package com.bhaskar.workout_helper_app;
import android.app.Activity;
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.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class CountActivity extends Activity implements SensorEventListener {
private float mLastZ,mLastY,mLastX;
private int stepcount;
private TextView tv;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
private Boolean mInitialized;
// constants
private final float LEG_THRSHOLD_AMPLITUDE = (float) 5.0;
private static final float NOISE = (float) 2.0;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.countactivity);
// initialise variables
stepcount = 0;
tv = (TextView) findViewById(R.id.textView3);
mInitialized=false;
// initialise sensor manager and check whether accelerometer is present
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager
.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
if (mAccelerometer == null) {
Log.d("HARDWARE", "ACCELEROMETER NOT PRESENT!!!");
startActivity(new Intent(CountActivity.this, workoutdata.class));
} else {
if (mAccelerometer.getMinDelay() != 0) {
Log.d("ACCELEROMETER",
"reports data only when the value of accelerometer is changed!!!");
//tv.setText("at regular interval "+SensorManager.SENSOR_DELAY_NORMAL);
}
mSensorManager.registerListener(this, mAccelerometer,
SensorManager.SENSOR_DELAY_NORMAL);
}
Button b = (Button) findViewById(R.id.button1);
b.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
tv.setText(stepcount);
// TODO Auto-generated method stub
startActivity(new Intent(CountActivity.this, MainActivity.class));
}
});
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// TODO Auto-generated method stub
}
@Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER) {
return;
}
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
if(Math.abs(z) > LEG_THRSHOLD_AMPLITUDE)
stepcount++;
}
@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
if (mAccelerometer != null)
mSensorManager.registerListener(this, mAccelerometer,
SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
if (mAccelerometer != null)
mSensorManager.unregisterListener(this);
}
}
但是每当我在手机上测试它时它就会崩溃,请帮助我该怎么办?