android 传感器使用 Compass指南针的实现功能

以下是指南针通过方向传感器而旋转实现。

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>

在这里给大家分享一下指南针图片znz：