Android 利用方向傳感器實現(xiàn)指南針具體步驟

更新時間：2013年06月02日 15:42:57 作者：

Android利用方向傳感器實現(xiàn)指南針功能，聽起來還不錯吧，下面與大家分享下具體的實現(xiàn)步驟，感興趣的朋友可以參考下哈

step1:新建一個項目Compass,并將一張指南針圖片導(dǎo)入到res/drawable-hdpi目錄中

step2:設(shè)計應(yīng)用的UI界面,main.xml

 
<SPAN style="FONT-SIZE: 18px"><STRONG><?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:gravity="center" 
> 
<ImageView 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:src="@drawable/compass" 
android:id="@+id/imageView" 
/> 
</LinearLayout></STRONG></SPAN> 

step3：MainActivity.java

復(fù)制代碼代碼如下:

 
import android.app.Activity; 
import android.content.Context; 
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 MainActivity extends Activity { 
private ImageView imageView; 
/** 傳感器管理器 */ 
private SensorManager manager; 
private SensorListener listener = new SensorListener(); 
@Override 
public void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.main); 
imageView = (ImageView) this.findViewById(R.id.imageView); 
imageView.setKeepScreenOn(true);//屏幕高亮 
//獲取系統(tǒng)服務(wù)（SENSOR_SERVICE)返回一個SensorManager 對象 
manager = (SensorManager) getSystemService(Context.SENSOR_SERVICE); 
} 
@Override 
protected void onResume() { 
/** 
* 獲取方向傳感器 
* 通過SensorManager對象獲取相應(yīng)的Sensor類型的對象 
*/ 
Sensor sensor = manager.getDefaultSensor(Sensor.TYPE_ORIENTATION); 
//應(yīng)用在前臺時候注冊監(jiān)聽器 
manager.registerListener(listener, sensor, 
SensorManager.SENSOR_DELAY_GAME); 
super.onResume(); 
} 
@Override 
protected void onPause() { 
//應(yīng)用不在前臺時候銷毀掉監(jiān)聽器 
manager.unregisterListener(listener); 
super.onPause(); 
} 
private final class SensorListener implements SensorEventListener { 
private float predegree = 0; 
@Override 
public void onSensorChanged(SensorEvent event) { 
/** 
* values[0]: x-axis 方向加速度 
　　 values[1]: y-axis 方向加速度 
　　 values[2]: z-axis 方向加速度 
*/ 
float degree = event.values[0];// 存放了方向值 
/**動畫效果*/ 
RotateAnimation animation = new RotateAnimation(predegree, degree, 
Animation.RELATIVE_TO_SELF,0.5f,Animation.RELATIVE_TO_SELF,0.5f); 
animation.setDuration(200); 
imageView.startAnimation(animation); 
predegree=-degree; 

/** 
float x=event.values[SensorManager.DATA_X]; 
float y=event.values[SensorManager.DATA_Y]; 
float z=event.values[SensorManager.DATA_Z]; 
Log.i("XYZ", "x="+(int)x+",y="+(int)y+",z="+(int)z); 
*/ 
} 
@Override 
public void onAccuracyChanged(Sensor sensor, int accuracy) { 
} 
} 
} 

step4:AndroidManifest.xml

復(fù)制代碼代碼如下:

 
<SPAN style="FONT-SIZE: 18px"><STRONG><?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
package="cn.roco.sensor" 
android:versionCode="1" 
android:versionName="1.0"> 
<uses-sdk android:minSdkVersion="8" /> 
<application android:icon="@drawable/icon" android:label="@string/app_name"> 
<activity android:name="MainActivity" 
android:label="@string/app_name"> 
<intent-filter> 
<action android:name="android.intent.action.MAIN" /> 
<category android:name="android.intent.category.LAUNCHER" /> 
</intent-filter> 
</activity> 
</application> 
</manifest></STRONG></SPAN> 