android 感應器使用 Compass指南針的實現功能

以下是指南針通過方向感應器而旋轉實現。 CompassDemo.java：  

package com.example.activity;    import android.app.Activity;  import android.hardware.Sensor;  import android.hardware.SensorEvent;  import android.hardware.SensorEventListener;  import android.hardware.SensorManager;  import android.os.Bundle;  import android.view.animation.Animation;  import android.view.animation.RotateAnimation;  import android.widget.ImageView;    public class CompassDemo extends Activity implements SensorEventListener {  private ImageView imageView;  SensorManager mSensorManager;  private float currentDegree=0f;      @Override  protected void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);      setContentView(R.layout.compass);      imageView=(ImageView)findViewById(R.id.znzImage);      mSensorManager=(SensorManager)getSystemService(SENSOR_SERVICE);  }              @Override      protected void onResume() {          mSensorManager.registerListener(this,mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION), SensorManager.SENSOR_DELAY_GAME);          super.onResume();      }                  @Override      protected void onPause() {          mSensorManager.unregisterListener(this);          super.onPause();      }                @Override      protected void onStop() {          mSensorManager.unregisterListener(this);          super.onStop();      }          @Override      public void onAccuracyChanged(Sensor arg0, int arg1) {                  }        @Override      public void onSensorChanged(SensorEvent event) {      int sensortype=event.sensor.getType();      switch(sensortype){      case Sensor.TYPE_ORIENTATION:          float degree=event.values[0];          RotateAnimation ra=new RotateAnimation(currentDegree,-degree,Animation.RELATIVE_TO_SELF,0.5f,Animation.RELATIVE_TO_SELF,0.5f);          ra.setDuration(200);          imageView.startAnimation(ra);          currentDegree=-degree;          break;      }        }    }  

 

  compass.xml： 

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"      android:orientation="vertical"      android:layout_width="fill_parent"      android:layout_height="fill_parent"      android:background="#fff"      >  <ImageView      android:id="@+id/znzImage"      android:layout_width="fill_parent"      android:layout_height="fill_parent"      android:scaleType="fitCenter"      android:src="@drawable/znz" />  </LinearLayout>  

 

  在這裡給大家分享一下指南針圖片znz：