Stopping & Starting music on incoming calls

问题

I have implemented an Activity that plays media from a URL in android

In order to add pause functionality when the incoming call is incoming I created a receiver that sets a a variable when the call is coming. The activity reads this variable and then pauses the music in its onPause() method and resets is when the call is done and the activity resumes the music in its onResume() method

This works fine as long the activity has the focus. If I go back to home screen while the music is playing, and then the call comes, the activity\'s onpause is not called & hence i can\' stop & start the music

What is the way out for this? Anybody implemented a media player so that it intercepts incoming & outgoing calls at all the times & stops and starts the music correctly?

回答1:

There are a few things you can do:

First of all, you can listen for changes in the call state using a PhoneStateListener. You can register the listener in the TelephonyManager:

PhoneStateListener phoneStateListener = new PhoneStateListener() {
    @Override
    public void onCallStateChanged(int state, String incomingNumber) {
        if (state == TelephonyManager.CALL_STATE_RINGING) {
            //Incoming call: Pause music
        } else if(state == TelephonyManager.CALL_STATE_IDLE) {
            //Not in call: Play music
        } else if(state == TelephonyManager.CALL_STATE_OFFHOOK) {
            //A call is dialing, active or on hold
        }
        super.onCallStateChanged(state, incomingNumber);
    }
};
TelephonyManager mgr = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
if(mgr != null) {
    mgr.listen(phoneStateListener, PhoneStateListener.LISTEN_CALL_STATE);
}

Remember to unregister the listener when it's no longer needed using the PhoneStateListener.LISTEN_NONE:

TelephonyManager mgr = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
if(mgr != null) {
    mgr.listen(phoneStateListener, PhoneStateListener.LISTEN_NONE);
}

For more information read the documentation.

Another thing you can do is listening for the broadcast android.intent.action.PHONE_STATE. It will contain the extra TelephonyManager.EXTRA_STATE which will give you information about the call. Take a look at the documentation here.

Please note that you'll need the android.permission.READ_PHONE_STATE-permission in both cases.

回答2:

I think that AudioManager is the best and fast solution. Here there is my implementation example:

public class MyActivity extends Activity implements OnAudioFocusChangeListener {

private AudioManager mAudioManager;

@Override
public void onCreate(Bundle savedInstanceState) {
    ...
    mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
    mAudioManager.requestAudioFocus(this, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);
    ...
}

@Override
 public void onDestroy(){
     super.onDestroy();
     ...
     mAudioManager.abandonAudioFocus(this);
     ...
 }


@Override
public void onAudioFocusChange(int focusChange) {
    if(focusChange<=0) {
        //LOSS -> PAUSE
    } else {
        //GAIN -> PLAY
    }
}   

}

I hope it's helpful for you :-)

回答3:

OR - You can try a Receiver Application.

Create a Receiver named CallRecord.java

package com.example.callreceiver;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;

public class CallReceiver extends BroadcastReceiver{
    TelephonyManager telManager;
    Context context;

@Override
public void onReceive(Context context, Intent intent) {


    this.context=context;

    telManager = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
    telManager.listen(phoneListener, PhoneStateListener.LISTEN_CALL_STATE);

}

private final PhoneStateListener phoneListener = new PhoneStateListener() {
    @Override
    public void onCallStateChanged(int state, String incomingNumber) {
        try {
            switch (state) {
            case TelephonyManager.CALL_STATE_RINGING: {
                //PAUSE
            break;
            }
            case TelephonyManager.CALL_STATE_OFFHOOK: {

            break;
            }
            case TelephonyManager.CALL_STATE_IDLE: {
                //PLAY
            break;
            }
            default: { }
            }
            } catch (Exception ex) {

            }
        }
    };
 }

Then Add this line in manifest.xml file to register it on the App

<receiver android:name="CallReceiver" >
        <intent-filter>
            <action android:name="android.intent.action.PHONE_STATE" >
            </action>
        </intent-filter>
    </receiver>

回答4:

I think requestAudioFocus() should be able to handle this case automatically. You don't need to check call state explicitly.

Audio Focus is cooperative in nature. That is, applications are expected (and highly encouraged) to comply with the audio focus guidelines, but the rules are not enforced by the system. If an application wants to play loud music even after losing audio focus, nothing in the system will prevent that. However, the user is more likely to have a bad experience and will be more likely to uninstall the misbehaving application.

To request audio focus, you must call requestAudioFocus() from the AudioManager, as the example below demonstrates:

AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
int result = audioManager.requestAudioFocus(this, AudioManager.STREAM_MUSIC,
AudioManager.AUDIOFOCUS_GAIN);

if (result != AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
    // could not get audio focus.
}

回答5:

IMHO better way is described in off docs: http://developer.android.com/training/managing-audio/audio-focus.html

回答6:

For me idle state was coming while there was incoming call, the quick fix is to check in the broadcast receiver

BroadcastReceiver phonestatereceiver = new BroadcastReceiver() {
  @Override
  public void onReceive(Context context, Intent intent) {
    Bundle extras = intent.getExtras();
    if (extras != null) {
      String state = extras.getString(TelephonyManager.EXTRA_STATE);
      if (state.equals(TelephonyManager.EXTRA_STATE_RINGING)) {
        //pause here
      }
      else if (state.equals(TelephonyManager.EXTRA_STATE_OFFHOOK)) {
        //pause here
      }
      else if (state.equals(TelephonyManager.EXTRA_STATE_IDLE)) {
        //play here
      }
    }
  }
};

来源：https://stackoverflow.com/questions/5610464/stopping-starting-music-on-incoming-calls