Question

我写了一个简单的android代码，它可以监听加速度和方向传感器，并将加速度x，y，z值和天使写入北方。

在app中我试图将传感器事件发送到onSensorChanged（）函数之间设置30秒的时间间隔，但它仍然每秒更新几次。

这是代码：

package com.example.sensors;

import java.util.List;

import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.app.Activity;
import android.hardware.Sensor;
import android.hardware.SensorEvent;

public class MainActivity extends Activity implements SensorEventListener{

     private SensorManager sensorManager;
       @Override
       protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
          sensorManager = (SensorManager)this.getSystemService(SENSOR_SERVICE);
    }

       @Override
       public boolean onCreateOptionsMenu(Menu menu) {
          // Inflate the menu; this adds items to the action bar if it is present.
          getMenuInflater().inflate(R.menu.main, menu);
          return true;
       }

       @Override
       public void onSensorChanged(SensorEvent event) {
             if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) //
             {
                 float x = event.values[0];
                 float y = event.values[1];
                 float z = event.values[2];
                 Log.i("acceleration:", "x, y, z" + " " + x + " " + y + " " + z + " ");  
             }               
             else if (event.sensor.getType() == Sensor.TYPE_ORIENTATION) //@deprecated. use TYPE_MAGNETIC_FIELD
             {
                 Log.i("orentation: " , "north:" + event.values[0]);
             }
         }

         @Override
         public void onAccuracyChanged(Sensor sensor, int accuracy) {

         }

         @Override
         protected void onResume() {
           super.onResume();
           // register this class as a listener for the accelerometer sensors and orientation
           sensorManager.registerListener(this,
               sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),//This method get the default sensor for a given type
               30000000);//SensorManager.SENSOR_DELAY_NORMAL
           sensorManager.registerListener(this,
                   sensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION),//This method get the default sensor for a given type
                   30000000); 
         }

         @Override
         protected void onPause() {
           // unregister listener
           super.onPause();
           sensorManager.unregisterListener(this);
         }

}

Answer 1

您无法为传感器费率设置自定义间隔。可能的最慢速率是SENSOR_DELAY_UI，每秒的采样取决于设备。您需要通过保存上次打印值来过滤这些值，然后等到该时间与当前时间之间的差异超过30秒并再次打印。

传感器监听器之间的android间隔

1 个答案: