Android keep screen on

mzafers

Hello, I want to keep my android tablet screen on always. I've tried these lines below, but it doesn't work. How can we do that with Qt 5.5.1?

If I lock tablet screen with button and then unlock screen with button, the codes work and tablet screen always on.
If I wait until screen off automaticly and then unlock screen with button, the codes work and tablet screen always on.
I tried with QTimer and seperated class and called the KeepScreenOn function every 5 secs, it didn't work, screen goes off.
The codes work with Qt 5.4.2.

Any idea?

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QAndroidJniObject>
#include <QtAndroid>
#include <QtAndroidExtras/QAndroidJniObject>
void KeepScreenOn()
{
    QAndroidJniObject activity = QtAndroid::androidActivity();
    if (activity.isValid())
    {
        QAndroidJniObject window = activity.callObjectMethod("getWindow", "()Landroid/view/Window;");
        if (window.isValid())
        {
            const int FLAG_KEEP_SCREEN_ON = 128;
            //window.callObjectMethod("addFlags", "(I)V", FLAG_KEEP_SCREEN_ON); // Method 1
            window.callMethod<void>("addFlags", "(I)V", FLAG_KEEP_SCREEN_ON); // Method 2
        }
    }
}

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    QQmlApplicationEngine engine;
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
    KeepScreenOn();
    return app.exec();
}

GBergamo

Same problem for me. Is this a bug? Are you sure it works for Qt 5.4.2?

Malek_Khlif

You can do this with Androidmanifet.xml

GBergamo

I solved the problem.
It seems that the only way to make it work is to extend the QtActivity.java class and add two methods that will be called from c++ using jni.

This is the java code:

public void disableIdleTimer()
{
    this.runOnUiThread(new Runnable()
    {
        public void run()
        {
            Log.w(QtApplication.QtTAG, "UIActivity::disableIdleTimer");
            getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        }
    } );
}

public void enableIdleTimer()
{
    this.runOnUiThread(new Runnable()
    {
        public void run()
        {
            Log.w(QtApplication.QtTAG, "UIActivity::enableIdleTimer");
            getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        }
    } );
}

mzafers

Yes, definitely it was work with Qt 5.4.2. In fact, I solved it on Java side.
https://forum.qt.io/topic/57625/solved-keep-android-5-screen-on/2

But it does not work with QAndroidJniObject.