Android Question Unable to record second video on a locked phone

toby · Jan 14, 2021

I want to find out whether I can start/stop video recording repeatedly from a service on a locked phone.

I started with the Camera2 library example(B4XPage version, https://www.b4x.com/android/forum/threads/camera2-still-images-and-videos.83920/) and made following minor modifications:
1. Added DrawOverPermission class
2. Added a service that restarts every 1 minute and that records a 30-second video

B4X:

Sub Service_Start (StartingIntent As Intent)
    'Service.StopAutomaticForeground 'Call this when the background task completes (if there is one)
    Service.AutomaticForegroundMode=Service.AUTOMATIC_FOREGROUND_ALWAYS
    StartServiceAt(Me, DateTime.Now+60000, True)
    StartActivity(Main)
    Dim Mainpage As B4XMainPage
    Mainpage=B4XPages.GetPage("MainPage")
    Mainpage.btnRecord_Click  'start recording
    Sleep(30000)
    Mainpage.btnRecord_Click  'stop recording
End Sub

3. Set VideoMode=True and request RECORD_AUDIO permission in B4XPage_Created()
4. Commented out: cam.stop in B4XPage_Background and openCamera() in B4XPage_Foreground

The results:
1. The first recording, 1.mp4, was recorded and saved correctly
2. It failed while trying to record the second time with the following log entries:

start called in an invalid state: 1
Error: (IllegalStateException) java.lang.IllegalStateException
** Activity (main) Pause event (activity is not paused). **
*** mainpage: B4XPage_Disappear [mainpage]
*** mainpage: B4XPage_Background [mainpage]
*** mainpage: B4XPage_PermissionResult [mainpage]
** Activity (main) Resume **
*** mainpage: B4XPage_Foreground [mainpage]
*** mainpage: B4XPage_Appear [mainpage]
[SurfaceTexture-1-22629-1] cancelBuffer: BufferQueue has been abandoned
uid=10131(com.ddg.camera2) Binder:22629_1 identical 3 lines
[SurfaceTexture-1-22629-1] cancelBuffer: BufferQueue has been abandoned
[SurfaceTexture-1-22629-1] connect: BufferQueue has been abandoned
[SurfaceTexture-1-22629-1] setMaxDequeuedBufferCount: BufferQueue has been abandoned

My question: Is it possible to somehow make the camera in a valid state for each subsequent recording? If so, some guide would be appreciated.

Logger connected to: asus ASUS_X017DA
--------- beginning of main
Not starting debugger since process cannot load the jdwp agent.
Connecting to perf service.
SetAppTypeFace- try to flip, app = com.ddg.camera2
Typeface getFontPathFlipFont - systemFont = default#default
SetAppTypeFace- try to flip, app = com.ddg.camera2
Typeface getFontPathFlipFont - systemFont = default#default
common created.
Starting remote logger. Port: 15174
Skia GL Pipeline
*** Service (starter) Create ***
** Service (starter) Start **
QUALCOMM build : cf57c9c, I1cb5c4d1cc
Build Date : 10/15/18
OpenGL ES Shader Compiler Version: EV031.25.03.01
Local Branch :
Remote Branch : refs/tags/AU_LINUX_ANDROID_LA.UM.7.2.R1.09.00.00.442.049
Remote Branch : NONE
Reconstruct Branch : NOTHING
Build Config : S L 6.0.7 AArch64
Loading /vendor/lib64/hw/gralloc.sdm660.so from current namespace instead of sphal namespace.
** Activity (main) Create, isFirst = true **
type=1400 audit(0.0:891): avc: denied { search } for name="proc" dev="debugfs" ino=11655 scontext=u:r:untrusted_app:s0:c131,c256,c512,c768 tcontext=u

bject_r:qti_debugfs:s0 tclass=dir permissive=0
PFP: 0x005ff110, ME: 0x005ff066
android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasWideColorDisplay retrieved: 0
android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasHDRDisplay retrieved: 0
Initialized EGL, version 1.4
Swap behavior 2
*** : B4XPage_Foreground
*** mainpage: B4XPage_Appear
Call B4XPages.GetManager.LogEvents = True to enable logging B4XPages events.
** Activity (main) Resume **
Loading /vendor/lib64/hw/[email protected] from current namespace instead of sphal namespace.
Loading /vendor/lib64/hw/gralloc.sdm660.so from current namespace instead of sphal namespace.
Permission: true
*** mainpage: B4XPage_PermissionResult [mainpage]
Connecting to camera service
Access denied finding property "vendor.camera.aux.packagelist"
type=1400 audit(0.0:892): avc: denied { read } for name="u