Android 听筒模式 实现
jopen
11年前
一、利用距离感应器监听听筒靠近耳朵事件
准确的说距离感应器并不能监听到你是否把手机靠近耳朵，也许是你用手挡在了距离感应器前面，但这不是我们关心的，我们关心的是当你的耳朵靠近听筒时，我们要捕获到这个事件step 1，新建实现SensorEventListener接口的类并实现onSensorChanged(SensorEvent event)方法
public class MainActivity extends Activity implements SensorEventListener
step 2，得到距离感应器的实例
audioManager = (AudioManager) this .getSystemService(Context.AUDIO_SERVICE); mSensorManager = (SensorManager) getSystemService (Context.SENSOR_SERVICE); mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY);
step 3，在onSensorChanged方法中判断是否靠近听筒
public void onSensorChanged(SensorEvent event) { // TODO Auto-generated method stub float range = event.values[0]; if (range == mSensor.getMaximumRange()) { Toast.makeText(this, "正常模式", Toast.LENGTH_LONG).show(); } else { Toast.makeText(this, "听筒模式", Toast.LENGTH_LONG).show(); }step 4, 向SensorManager注册监听距离感应器
@Override protected void onResume() { mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_NORMAL); super.onResume(); } @Override protected void onPause() { mSensorManager.unregisterListener(this); super.onPause(); }二、根据距离感应器改变AudioManager播放模式
默认情况下，播放语音都是用外置喇叭或者耳机，我们需要编码实现播放的切换。step 1，在AndroidManifest文件中添加权限声明
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
step 2，切换播放模式
public void onSensorChanged(SensorEvent event) { // TODO Auto-generated method stub float range = event.values[0]; if (range == mSensor.getMaximumRange()) { Toast.makeText(this, "正常模式", Toast.LENGTH_LONG).show(); audioManager.setMode(AudioManager.MODE_NORMAL); } else { Toast.makeText(this, "听筒模式", Toast.LENGTH_LONG).show(); audioManager.setMode(AudioManager.MODE_IN_CALL); }完整代码：
package com.markjoker.sensortest; import java.io.FileInputStream; import java.io.IOException; import android.hardware.Sensor; import android.hardware.SensorEvent; import android.hardware.SensorEventListener; import android.hardware.SensorManager; import android.media.AudioManager; import android.media.MediaPlayer; import android.os.Bundle; import android.app.Activity; import android.content.Context; import android.util.Log; import android.view.Menu; import android.widget.Toast; public class MainActivity extends Activity implements SensorEventListener { private AudioManager audioManager; private SensorManager mSensorManager; private Sensor mSensor; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); init(); } private void init() { audioManager = (AudioManager) this .getSystemService(Context.AUDIO_SERVICE); mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE); mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY); MediaPlayer mPlayer = new MediaPlayer(); try { mPlayer.reset(); mPlayer.setDataSource(new FileInputStream("/sdcard/snow.mp3").getFD()); mPlayer.prepare(); mPlayer.start(); } catch (IllegalArgumentException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (SecurityException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IllegalStateException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } @Override protected void onResume() { mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_NORMAL); super.onResume(); } @Override protected void onPause() { // TODO Auto-generated method stub mSensorManager.unregisterListener(this); super.onPause(); } @Override public void onSensorChanged(SensorEvent event) { // TODO Auto-generated method stub float range = event.values[0]; if (range == mSensor.getMaximumRange()) { Toast.makeText(this, "正常模式", Toast.LENGTH_LONG).show(); audioManager.setMode(AudioManager.MODE_NORMAL); } else { Toast.makeText(this, "听筒模式", Toast.LENGTH_LONG).show(); audioManager.setMode(AudioManager.MODE_IN_CALL); } } @Override public void onAccuracyChanged(Sensor sensor, int accuracy) { // TODO Auto-generated method stub } }