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androidc++qtqandroidjniobject

Unable to call PowerManager.WakeLock.newWakeLock using QAndroidJniObject


I'm trying to execute this Java code:

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "My Tag");
wl.acquire();

using Qt QAndroidJniObject (I'm deploying a Qt app on Android).

I did that:

QAndroidJniObject activity = QAndroidJniObject::callStaticObjectMethod("org/qtproject/qt5/android/QtNative", "activity", "()Landroid/app/Activity;");
if ( activity.isValid() )
{
    QAndroidJniObject serviceName = QAndroidJniObject::getStaticObjectField<jstring>("android/content/Context","POWER_SERVICE");
    if ( serviceName.isValid() )
    {
        QAndroidJniObject powerMgr = activity.callObjectMethod("getSystemService", "(Ljava/lang/String;)Ljava/lang/Object;",serviceName.object<jobject>());
        if ( powerMgr.isValid() )
        {
            jint levelAndFlags = QAndroidJniObject::getStaticField<jint>("android/os/PowerManager","SCREEN_DIM_WAKE_LOCK");

            QAndroidJniObject tag = QAndroidJniObject::fromString( "My Tag" );

            QAndroidJniObject wakeLock = powerMgr.callObjectMethod("newWakeLock", "(ILjava/lang/String;)Landroid/os/PowerManager/WakeLock;", levelAndFlags,tag.object<jstring>());

            if ( wakeLock.isValid() )
                wakeLock.callMethod<void>("acquire", "()V");
            else
                assert( false );
        }
    }
}

Checked from the debugger: levelAndFlags is correct (6), tag is correct ("My Tag"), but wakeLock.isValid() returns false.

There must be a problem with this line:

QAndroidJniObject wakeLock = powerMgr.callObjectMethod("newWakeLock", "(ILjava/lang/String;)Landroid/os/PowerManager/WakeLock;", levelAndFlags,tag.object<jstring>());

But I can't figure out what...


Solution

  • Nested class names requires a special syntax:

    Landroid/os/PowerManager/WakeLock
    

    Should be:

    Landroid/os/PowerManager$WakeLock
    

    And it works!