问题
I am writing a android app which is supposed to play back a audio file when a call is in progress coming from a specific number .. I tried many approaches.. but all went in vein
- Separate Thread
- Listener on Telephone service
- starting a service in parallel
can any one please help me how to proceed regarding this ?
Update :
I am able to play a mp3 file on call recieve and i am able to play it load on speaker.. but how ever loud i play the calling party is not able to listen to it.... is there anyway i can push the speaker stream to call stream
回答1:
From the api doc here
Note: You can play back the audio data only to the standard output device. Currently, that is the mobile device speaker or a Bluetooth headset. You cannot play sound files in the conversation audio during a call.
So from this and lots of other so answers we can conclude that we can not play an audio during a call process.
But a long time ago from a personal experience with a handset I got a result where the audiotrack was playing while there was a call established and both the voices were heard at the same time. So I think this depends on handsets if it allows it then you can play.
You can try another thing experimentally. play the audio using a different route ( speakerphone or bluetooth).
Another option is to build your custom android build
来源：https://stackoverflow.com/questions/15588009/background-audio-for-a-call-in-progress-possible