Compass-指南針（主要用到RotateAnimation和SensorEventListener）

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="fill_parent"
	android:layout_height="fill_parent"
	android:background="#fff"
	>
<ImageView
	android:id="@+id/znzImage"
	android:layout_width="150dip"
	android:layout_height="150dip"
	android:scaleType="fitCenter"
	android:src="@drawable/znz"/>
</LinearLayout>

package org.crazyit.sensor;

//import org.openintents.sensorsimulator.hardware.Sensor;
//import org.openintents.sensorsimulator.hardware.SensorEvent;
//import org.openintents.sensorsimulator.hardware.SensorEventListener;
//import org.openintents.sensorsimulator.hardware.SensorManagerSimulator;

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.util.Log;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;

/**
 * Description:
 * <br/>site: <a href="http://www.crazyit.org">crazyit.org</a> 
 * <br/>Copyright (C), 2001-2012, Yeeku.H.Lee0
 * <br/>This program is protected by copyright laws.
 * <br/>Program Name:
 * <br/>Date:
 * @author  Yeeku.H.Lee [email protected]
 * @version  1.0
 */
public class Compass extends Activity
	implements SensorEventListener
{
	// 定義顯示指南針的圖片
	ImageView znzImage;
	// 記錄指南針圖片轉過的角度
	float currentDegree = 0f;
	// 定義模擬器的Sensor管理器
//	private SensorManagerSimulator mSensorManager;

	 // 定義真機的Sensor管理器
	SensorManager mSensorManager;
	@Override
	public void onCreate(Bundle savedInstanceState)
	{
		Log.i("hyz", "Compass->onCreate()");
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		// 獲取界面中顯示指南針的圖片
		znzImage = (ImageView) findViewById(R.id.znzImage);

		 // 獲取真機的傳感器管理服務
		 mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
//		// 獲取傳感器模擬器的傳感器管理服務
//		mSensorManager = SensorManagerSimulator.getSystemService(this,
//			SENSOR_SERVICE);
//		// 連接傳感器模擬器
//		mSensorManager.connectSimulator();
	}

	@Override
	protected void onResume()
	{
		Log.i("hyz", "Compass->onResume()");
		super.onResume();
		// 爲系統的方向傳感器註冊監聽器
		mSensorManager.registerListener(this,
			mSensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION),
			SensorManager.SENSOR_DELAY_GAME);
	}

	@Override
	protected void onPause()
	{
		Log.i("hyz", "Compass->onPause()");
		// 取消註冊
		mSensorManager.unregisterListener(this);
		super.onPause();
	}

	@Override
	protected void onStop()
	{
		Log.i("hyz", "Compass->onStop()");
		// 取消註冊
		mSensorManager.unregisterListener(this);
		super.onStop();
	}

	@Override
	public void onSensorChanged(SensorEvent event)
	{
		//Log.i("hyz", "Compass->onSensorChanged()");
		// 真機上獲取觸發event的傳感器類型
		int sensorType = event.sensor.getType();
//		// 模擬器上獲取觸發event的傳感器類型
//		int sensorType = event.type;
		switch (sensorType)
		{
			case Sensor.TYPE_ORIENTATION:
				// 獲取繞Z軸轉過的角度。
				float degree = event.values[0];
				// 創建旋轉動畫（反向轉過degree度）
				RotateAnimation ra = new RotateAnimation(
						currentDegree,	-degree, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);
				// 設置動畫的持續時間
				ra.setDuration(0);
				// 運行動畫
				znzImage.startAnimation(ra);
				currentDegree = -degree;
				break;
		}
	}

	@Override
	public void onAccuracyChanged(Sensor sensor, int accuracy)
	{
		Log.i("hyz", "Compass->onAccuracyChanged()");
	}
}