Qt Android Services. Documentation and reality.

[KroMignon]

@T-Kloczko I've got a little question to you: how to you know service is started or not?
Your Android Service and Activity runs in different processes, but with Qt Creator you can only debug 1 process, which will be the Activity.

To see if you Service has started, you have to use a tool to monitor android logs, for example with Android Studio or mLogCat.

[T. Kloczko]

@KroMignon Hi, yes we use ncat stuff to trace that the service was started.
Now we gonna try to launch the websocket server through a call to a static c function... we'll see :-/ !
Thib.

[T. Kloczko]

@KroMignon Hi, finally I used logcat stuff from Android and here is the log I obtain:

2020-04-06 11:39:16.713 9577-9577/? I/r.inria.test:q: Not late-enabling -Xcheck:jni (already on)
2020-04-06 11:39:16.743 9577-9577/? E/r.inria.test:q: Unknown bits set in runtime_flags: 0x8000
2020-04-06 11:39:16.744 9577-9577/? W/r.inria.test:q: Unexpected CPU variant for X86 using defaults: x86
2020-04-06 11:39:16.798 9577-9577/fr.inria.test:qt D/SERVICE: ON CREATE CALLED
2020-04-06 11:39:16.798 9577-9577/fr.inria.test:qt I/Service: Created
2020-04-06 11:39:16.800 9577-9577/fr.inria.test:qt E/r.inria.test:q: Invalid ID 0x00000000.
2020-04-06 11:39:16.802 9577-9577/fr.inria.test:qt E/Qt: Can't create main activity
    android.content.res.Resources$NotFoundException: String array resource ID #0x0
        at android.content.res.Resources.getStringArray(Resources.java:604)
        at org.qtproject.qt5.android.bindings.QtLoader.startApp(QtLoader.java:423)
        at org.qtproject.qt5.android.bindings.QtServiceLoader.onCreate(QtServiceLoader.java:60)
        at org.qtproject.qt5.android.bindings.QtService.onCreateHook(QtService.java:54)
        at org.qtproject.qt5.android.bindings.QtService.onCreate(QtService.java:60)
        at fr.inria.test.MyTest.onCreate(MyTest.java:29)
        at android.app.ActivityThread.handleCreateService(ActivityThread.java:3953)
        at android.app.ActivityThread.access$1500(ActivityThread.java:219)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1875)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-04-06 11:39:16.802 9577-9577/fr.inria.test:qt I/Service: Created

It seems that it wants to create another main activity... I am really lost...
Thib

[T. Kloczko]

@KroMignon I FOUND IT !!!!
Thanks to this thread:
https://lists.qt-project.org/pipermail/interest/2020-January/034372.html
In fact, at least for Qt 5.14. x, the part of the manifest that must be used is as follows:

 <service android:process=":in" android:name=".MyTest" android:exported="true">
        <!-- android:process=":qt" is needed to force the service to run on a separate process than the Activity -->

            <!-- Application arguments -->
            <meta-data android:name="android.app.arguments" android:value="-service"/>
            <!-- Application arguments -->

            <!-- If you are using the same application (.so file) for activity and also for service, then you
                 need to use *android.app.arguments* to pass some arguments to your service in order to know which
                 one is which.
            -->

            <!-- Application to launch -->
            <meta-data android:name="android.app.lib_name" android:value="-- %%INSERT_APP_LIB_NAME%% --"/>
            <!-- Application to launch -->

            <!-- Ministro -->
            <meta-data android:name="android.app.qt_sources_resource_id" android:resource="@array/qt_sources"/>
            <meta-data android:name="android.app.repository" android:value="default"/>
            <meta-data android:name="android.app.qt_libs_resource_id" android:resource="@array/qt_libs"/>
            <meta-data android:name="android.app.bundled_libs_resource_id" android:resource="@array/bundled_libs"/>
            <!-- Ministro -->

            <!-- Deploy Qt libs as part of package -->
            <meta-data android:name="android.app.bundle_local_qt_libs" android:value="-- %%BUNDLE_LOCAL_QT_LIBS%% --"/>
            <!-- Deploy Qt libs as part of package -->

            <!-- Run with local libs -->
            <meta-data android:name="android.app.use_local_qt_libs" android:value="-- %%USE_LOCAL_QT_LIBS%% --"/>
            <meta-data android:name="android.app.libs_prefix" android:value="/data/local/tmp/qt/"/>
            <meta-data android:name="android.app.load_local_libs_resource_id" android:resource="@array/load_local_libs"/>
            <meta-data android:name="android.app.load_local_jars" android:value="-- %%INSERT_LOCAL_JARS%% --"/>
            <meta-data android:name="android.app.static_init_classes" android:value="-- %%INSERT_INIT_CLASSES%% --"/>
            <!-- Run with local libs -->

            <!--  Messages maps -->
            <meta-data android:value="@string/ministro_not_found_msg" android:name="android.app.ministro_not_found_msg"/>
            <meta-data android:value="@string/ministro_needed_msg" android:name="android.app.ministro_needed_msg"/>
            <meta-data android:value="@string/fatal_error_msg" android:name="android.app.fatal_error_msg"/>
            <meta-data android:value="@string/unsupported_android_version" android:name="android.app.unsupported_android_version"/>
            <!--  Messages maps -->


            <!-- Background running -->
            <meta-data android:name="android.app.background_running" android:value="true"/>
            <!-- Background running -->
        </service>

Compare to the one given https://wiki.qt.io/AndroidServices, one should remove the following lines:

<meta-data android:name="android.app.bundled_in_lib_resource_id" android:resource="@array/bundled_in_lib"/>
<meta-data android:name="android.app.bundled_in_assets_resource_id" android:resource="@array/bundled_in_assets"/>

One should replace the following line:

<meta-data android:name="android.app.load_local_libs" android:value="-- %%INSERT_LOCAL_LIBS%% --"/>

by this one

<meta-data android:name="android.app.load_local_libs_resource_id" android:resource="@array/load_local_libs"/>

And finally, one has to add the following line:

<meta-data android:value="@string/unsupported_android_version" android:name="android.app.unsupported_android_version"/>

Clearly, the wiki should at least mention this ;-) !

Thanks again for the help,
Sincerely,
Thibaud.

[Pablo J. Rogina]

@T-Kloczko said in Qt Android Services. Documentation and reality.:

I FOUND IT !!!!

It looks like you solved your issue. If so, please don't forget to mark your post as such.

the wiki should at least mention this ;-) !

You're more than welcome to edit/improve the wiki, just login using the same account you use in this forum.

Thanks.

[T. Kloczko]

@Pablo-J-Rogina OK thanks ! I would like to do it but it seems I have not enough privilege.

For the wiki part, I tried to modify it but I realize I was not logged :-/ !

Thanks again for the work the whole team does !

Cheers Thibaud.

[T. Kloczko]

@Pablo-J-Rogina In fact it seems that I do not have enough privilege to mark it as the right answer :-( ...

[SGaist]

Hi,

IIRC, that's an issue of NodeBB. Which answer would you like to mark as the right one ?

[T. Kloczko]

@SGaist Hi, the right answer is the one of 8 hours ago.

[SGaist]

Is it correct ?

[Kanstancin]

@T-Kloczko Hi!
I've faced the same issue, but after I made fixes proposed by you to AndroidManifest, the problem still had not solved.
Please, if you managed to start the service from the application, can you post somewhere a minimal working example of the project?

Thanks in advance,
Kastuś.