Android Question AudioStreamer & Service

[Midimaster]

I use Erel's code sample "beep" to create code playing audio via the AudioStreamer. It works already, but now I had a crash without any debug feedback, the smartphone hang. So I asked me, whether my way is already correct. On the other side I do not really understand the co-operation of MAIN() and STARTER().

Every second I tranfer new Bytes to the already open AudioStreamer.

that is what I'm doing:

...

Sub SendMoreSamples
    ....
    Private AudioOutBytes() As Byte
    ' fill them
    ....
    CallSub2(Starter, "SendToAudio", AudioOutBytes)
End Sub

#Region  Service Attributes
    #StartAtBoot: False
    #ExcludeFromLibrary: True
#End Region



Sub Process_Globals
    Public AudioOut As AudioStreamer
End Sub



Sub Service_Create
    AudioOut.Initialize("AudioOut",22100,True,16,AudioOut.VOLUME_MUSIC)
    AudioOut.StartPlaying
End Sub



Public Sub SendToAudio(Bytes() As Byte)
    AudioOut.Write(Bytes)
End Sub



Sub Service_Start (StartingIntent As Intent)
    Service.StopAutomaticForeground
End Sub



Sub Service_TaskRemoved
End Sub


Sub Application_Error (Error As Exception, StackTrace As String) As Boolean
    Return True
End Sub



Sub Service_Destroy
End Sub

Now my Questions are:

1. Do I need to stop the AudioStreamer, when I finish the app? For me it is important to keep the player open during app is open. So I cannot add a NULL byte at the end of the transfered Byte()-Array like Erel suggested in his example.

2. And where can I add the code for stopping it?

3. How can I react on Events from the AudioStreamer? Which events are avaiable? Why can I not see the possible Event-related Subs of the AudioStreamer in my code? It looks like the AudioStreamer is unknown in my MAIN.

 

[JohnC]

I don't know what type of sound you are playing, but if you only want to play a simple sound file, I would recommend SoundPool:

B4A - Audio

 

[Midimaster]

I think I did not write anything about a simple sound file.... Its a project where the app plays 20 instrument tracks simultan. Each track is 4-5min and 10-20MB. the user can switch on/off and adjust the volume of each instrument in real time.

It is already working, time consumption and memory are no problems any more. Now I only need to know, what to do with the AudioStreamer object, when leaving or pausing the app.

 

[OliverA]

On the other side I do not really understand the co-operation of MAIN() and STARTER().

Have you read these (and watched the video)?
1) https://www.b4x.com/android/forum/threads/android-process-and-activities-life-cycle.6487/
2) https://www.b4x.com/android/forum/threads/service-modules.7542/#content
3) https://www.b4x.com/android/forum/t...-consistent-single-entry-point.57599/#content
BTW, some of that is in the process of changing because of
1) https://www.b4x.com/android/forum/t...k-for-managing-multiple-pages.118901/#content

For me it is important to keep the player open during app is open

And where can I add the code for stopping it?

Instead of starting the playing in the Starter, you could start playing in Activity_Resume (open) and stop in Activity_Pause (close)

It looks like the AudioStreamer is unknown in my MAIN.

Because you declared it in the Starter?

Which events are avaiable?

To see events available, type

sub

followed by a space and then a tab. A box should box up with the types available (dependent on libraries active/selected in the libraries tab). Pick a type and then the events available list should show up. Might want to read some of the documentation on the B4X IDE found here: https://www.b4x.com/android/documentation.html

BTW, welcome!

 

[Cadenzo]

Not about your problem, but I think, it is better to use AudioStreamer in a Class, not in a Service. So you can reach it from everywhere with .SendToAudio, no need for CallSub.
And yes, you should close the AudioStreamer in Activity_Pause.