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Kevin Su

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语音播放之普通模式和听筒模式

###语音播放之普通模式和听筒模式,含距离传感器[转载]

最近为了实现微信的语音播放听筒模式,上网查阅了一些资料,看到一篇写得很完整的文章,特意转载一下

####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(); }

####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

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
 
}

}

原文链接