取得Android平台某设备上所有可用的Sensors

本来要写一个检测手机的温度的小应用，学习一下传感器的api,可结果怎么写不行。经检测，发现取得的Sensor为NULL，这才明白，我手机没有TYPE_AMBIENT_TEMPERATURE传感器。

于是写了一个APP列出所有的可用的Sensors。

(附编译后的APK: http://pan.baidu.com/s/1kToTpTt)

代码如下：

 package kempff.sensors;

 import java.util.List;

 import android.app.Activity;

 import android.hardware.Sensor;

 import android.hardware.SensorManager;

 import android.os.Bundle;

 import android.widget.TextView;

 public class MainActivity extends Activity {

     private String mtext="";

     private TextView tv=null;

     private SensorManager sm=null;

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

         tv=(TextView)findViewById(R.id.msg);

         sm=(SensorManager)this.getSystemService(SENSOR_SERVICE);

         List<Sensor> sensors=sm.getSensorList(Sensor.TYPE_ALL);

         for(Sensor t:sensors){

             log("[Sensors]Name:"+t.getName()+";Vendor:"+t.getVendor());

         }

     }

     private void log(String s){

         mtext+=s+"\n";

         tv.setText(mtext);

     }

 }

编译后在手机上安装，输出结果果然没有AMBIENT_TEMPERATURE。在我手机上有个测温软件竟能检测温度，可能是用的CPU温度之类的方法，还没有弄明白。附上另一段利用温度传感器测温度的代码。

 package kempff.t001;

 import android.os.Bundle;

 import android.widget.TextView;

 import android.app.Activity;

 import android.hardware.*;

 public class MainActivity extends Activity implements SensorEventListener {

     private Sensor mtmp=null;

     private SensorManager msm=null;

     private TextView msg=null;

     private String mtext="";

     @Override

     protected void onCreate(Bundle savedInstanceState) {

         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_main);

         msg=(TextView)findViewById(R.id.msg);

         msm=(SensorManager)this.getSystemService(SENSOR_SERVICE);

         mtmp=msm.getDefaultSensor(Sensor.TYPE_AMBIENT_TEMPERATURE);

         if(mtmp==null){

             log("TYPE_AMBIENT_TEMPERATURE==NULL");

         }else{

             log("TYPE_AMBIENT_TEMPERATURE:"+mtmp.toString());

         }

     }

     @Override

     protected void onPause() {

         // TODO Auto-generated method stub

         super.onPause();

         msm.unregisterListener(this);

     }

     @Override

     protected void onResume() {

         // TODO Auto-generated method stub

         super.onResume();

         msm.registerListener(this, mtmp, SensorManager.SENSOR_DELAY_NORMAL);

     }

     @Override

     public void onAccuracyChanged(Sensor arg0, int arg1) {

         // TODO Auto-generated method stub

     }

     @Override

     public void onSensorChanged(SensorEvent event) {

         // TODO Auto-generated method stub

         for(float t:event.values){

             log(String.valueOf(t)+"\n");

         }

     }

     private void log(String txt){

         mtext+=txt;

         this.msg.setText(mtext);

     }

 }

这是Layout.xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

     xmlns:tools="http://schemas.android.com/tools"

     android:layout_width="match_parent"

     android:layout_height="match_parent"

     android:paddingBottom="@dimen/activity_vertical_margin"

     android:paddingLeft="@dimen/activity_horizontal_margin"

     android:paddingRight="@dimen/activity_horizontal_margin"

     android:paddingTop="@dimen/activity_vertical_margin"

     tools:context="kempff.t001.MainActivity" >

     <TextView

         android:id="@+id/msg"

         android:layout_width="fill_parent"

         android:layout_height="fill_parent"

         android:text="@string/hello_world" />

 </RelativeLayout>