简述建设网站的基本流程,wordpress 自定义字段插件,net网站建设教程,网站优化费用报价明细本文实例讲述了Android开发获取重力加速度和磁场强度的方法。分享给大家供大家参考#xff0c;具体如下#xff1a;Android获取重力加速度和磁场强度主要依靠#xff1a;Sensor.getRotationMatrix (float[] R, float[] I, float[] gravity, float[] geomagnetic)输入数据具体如下Android获取重力加速度和磁场强度主要依靠Sensor.getRotationMatrix (float[] R, float[] I, float[] gravity, float[] geomagnetic)输入数据gravity为重力传感器测得的重力加速度float[3]geomagnetic为罗盘传感器测得的地磁数据float[3]输出数据R为通过这个方法计算得到的从手机的设备到坐标系到真实世界坐标系的转换矩阵I为从将地磁数据转换到重力数据所在坐标的旋转矩阵[0 0 g] R * gravity (g 重力加速度)[0 m 0] I * R * geomagnetic (m 磁场强度)下面是我做的结果图核心部分代码如下public class MainActivity extends AppCompatActivity implements SensorEventListener {private static final String TAG CompassActivity;private SensorManager sensorManager;//记录rotationMatrix矩阵值private float[] r new float[9];private float[] gravity null;private float[] geomagnetic null;private float[] Inew float[9];private Handler handlernew Handler(){Overridepublic void handleMessage(Message msg) {if(gravity!nullgeomagnetic!null){if(SensorManager.getRotationMatrix(r, I, gravity, geomagnetic)) {float gri gravity[0] * r[6] gravity[1] * r[7] gravity[2] * r[8];float h (I[3]*r[0]I[4]*r[3]I[5]*r[6])*geomagnetic[0](I[3]*r[1]I[4]*r[4]I[5]*r[7])*geomagnetic[1](I[3]*r[2]I[4]*r[5]I[5]*r[8])*geomagnetic[2];TextView textView (TextView) findViewById(R.id.textView);textView.setText(重力加速度 gri \n磁场强度 h \n);}}}};Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);sensorManager (SensorManager) getSystemService(SENSOR_SERVICE);}Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.menu_main, menu);return true;}Overridepublic boolean onOptionsItemSelected(MenuItem item) {// Handle action bar item clicks here. The action bar will// automatically handle clicks on the Home/Up button, so long// as you specify a parent activity in AndroidManifest.xml.int id item.getItemId();//noinspection SimplifiableIfStatementif (id R.id.action_settings) {return true;}return super.onOptionsItemSelected(item);}Overridepublic void onSensorChanged(SensorEvent sensorEvent) {switch (sensorEvent.sensor.getType()){case Sensor.TYPE_ACCELEROMETER:gravitysensorEvent.values;handler.sendEmptyMessage(0);break;case Sensor.TYPE_MAGNETIC_FIELD:geomagneticsensorEvent.values;handler.sendEmptyMessage(0);break;default:break;}}Overridepublic void onAccuracyChanged(Sensor sensor, int i) {}private void showMessage(String message){View viewfindViewById(R.id.fab);final Snackbar snackbarSnackbar.make(view, message, Snackbar.LENGTH_INDEFINITE);snackbar.setAction(关闭, new View.OnClickListener() {Overridepublic void onClick(View view) {snackbar.dismiss();}});snackbar.show();}Overrideprotected void onPause() {super.onPause();sensorManager.unregisterListener(this);}Overrideprotected void onResume() {super.onResume();Sensor sensor1sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);sensorManager.registerListener(this,sensor1,SensorManager.SENSOR_DELAY_UI);Sensor sensor2sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);sensorManager.registerListener(this,sensor2,SensorManager.SENSOR_DELAY_UI);}}希望本文所述对大家Android程序设计有所帮助。
