Android back button is closing application

account35467

With the following code, pressing the back button on Android closes the application. I can see the "Accepted event" log message getting printed, but the app still closes. This is more important in a stack view where pressing the back button closes the application instead of going to the previous page.

import QtQuick.Controls
import QtQuick
import QtQuick.Layouts

ApplicationWindow {
    id: window
    width: 400
    height: 600
    visible: true
    title: "Test"

    onClosing: {
        close.accepted = false
        console.log("Close cancelled")
    }
    Item {
        focus: true
        anchors.fill: parent

        Keys.onPressed: event => {
                            if (event.key === Qt.Key_Back) {
                                console.log("Accepted event")
                                event.accepted = true
                            }
                        }

        Text {
            anchors.centerIn: parent
            text: "Hello"
        }
    }
}

J.Hilk

Argument injection is no longer supported and my be the problem here use a lambda :
this code works fine in my apps

What version of Qt and android are you targeting/using?

onClosing:(close)=> {
        //Management for Android Back-Button
        if(Qt.platform.os === "android"){
            close.accepted = false
        } else {
                close.accepted = true
         }
    }

account35467

What version of Qt

Qt 6.10.2

android are you targeting/using?

Are you referring to ANDROID_PLATFORM? its set to android-28 and I'm running it on a Pixel 4 simulator.

I created a new project with the following code:

import QtQuick.Controls
import QtQuick
import QtQuick.Layouts

ApplicationWindow {
    width: 640
    height: 480
    visible: true
    title: qsTr("Hello World")
    onClosing: close => {
                   //Management for Android Back-Button
                   if (Qt.platform.os === "android") {
                       console.log("Accepting event")
                       close.accepted = false
                   } else {
                       close.accepted = true
                   }
               }
}

#include <QGuiApplication>
#include <QQmlApplicationEngine>

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    QObject::connect(
        &engine,
        &QQmlApplicationEngine::objectCreationFailed,
        &app,
        []() { QCoreApplication::exit(-1); },
        Qt::QueuedConnection);
    engine.loadFromModule("helloqml", "Main");

    return app.exec();
}

The console.log() message is being printed, but the app still minimizes.

ADB log:

D/qml     : Accepting event
D/VRI[QtActivity]: visibilityChanged oldVisibility=true newVisibility=false
E/Surface : freeAllBuffers: 1 buffers were freed while being dequeued!
E/Surface : freeAllBuffers: 1 buffers were freed while being dequeued!
W/default : QRhiGles2: Failed to make context current. Expect bad things to happen.
W/default : Failed to start frame
W/WindowOnBackDispatcher: sendCancelIfRunning: isInProgress=false callback=android.app.Activity$$ExternalSyntheticLambda0@abe797f
D/qml     : Accepting event

account35467

Looks like this is a bug in 6.10.2. It works with both 6.9.3 and 6.11.0