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: