Proximity Sensor in Android example

                  

                      Proximity Sensor is used to determine how far the device is closer to an object. For example when user making/receiving a phone call, proximity sensor measures the distance between the device and the user's face.







I am going to implement this Proximity Sensor for playing/pause a music.

Steps to create the project::

• create an android project.
• create a layout xml with one textview (for updating playing/pause status).
• place one music file in raw directory under res directory.
• implement "SensorEventListener" interface and add unimplemented methods.
• register the listener for Proximity Sensor.
• play/pause the music based on the sensor.

activity_main.xml

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

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

    android:layout_width="fill_parent"

    android:layout_height="fill_parent" >

    <TextView

        android:id="@+id/textView2"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerHorizontal="true"

        android:layout_centerVertical="true"

        android:text="@string/hello_world"

        android:textAppearance="?android:attr/textAppearanceMedium"

        tools:context=".MainActivity" />

</RelativeLayout>

MainActivity.java

import java.io.IOException;

import android.hardware.Sensor;

import android.hardware.SensorEvent;

import android.hardware.SensorEventListener;

import android.hardware.SensorManager;

import android.media.MediaPlayer;

import android.os.Bundle;

import android.app.Activity;

import android.content.Context;

import android.view.Menu;

import android.widget.TextView;

import android.widget.Toast;

public class MainActivity extends Activity implements SensorEventListener{

    SensorManager sensorMgr;

    Sensor sensor;

    TextView textView;

    MediaPlayer player;

    boolean flag = false;

   

    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

       

        textView = (TextView)findViewById(R.id.textView2);

        sensorMgr = (SensorManager) getSystemService(Context.SENSOR_SERVICE);

        sensor = sensorMgr.getDefaultSensor(Sensor.TYPE_PROXIMITY);

       

        player = MediaPlayer.create(getApplicationContext(), R.raw.music_file);

        try {

            player.prepare();

        } catch (IllegalStateException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

   

    @Override

    protected void onResume() {

           super.onResume();

           sensorMgr.registerListener(this, sensor,SensorManager.SENSOR_DELAY_NORMAL);

    }

   

    @Override

    protected void onPause() {

        super.onPause();

        sensorMgr.unregisterListener(this);

        player.stop();

    }

   

    public void onAccuracyChanged(Sensor sensor, int accuracy) {       

    }

    public void onSensorChanged(SensorEvent event) {

        if(event.sensor.getType() == sensor.TYPE_PROXIMITY){

            if(event.values[0] == sensor.getMaximumRange()){

                if(flag == true){

                    player.pause();

                    textView.setText("Pause");

                    flag = false;

                }else{

                    player.start();

                    textView.setText("Now Playing..!");

                    flag = true;

                }  

            }

        }

    }

}

AndroidManifest.xml

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

    package="com.sathish.example.proximitysensor"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="7"

        android:targetSdkVersion="15" />

    <application

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name=".MainActivity"

            android:label="@string/title_activity_main" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

</manifest> 

screenshots

click here to download the source code.