Mobile and Embedded

@jporcher Can you try to change the scrolling speed? For example: tableWidget->setVerticalScrollMode( QAbstractItemView::ScrollPerPixel ); The default one could be too fast. Qt Widgets do have issues on touch screen(not only on phone screens). It may be hardware or drivers problem as well. Try another brand of phone to see if your app has the same problem.

@OldRoly your selection is not arm64_v8a in the second picture. And what is the Android version in your phone? Find out the compatibility of android version and jdk version.

@ljxiango maybe use qt code to check permissions. https://doc.qt.io/qt-6/qtandroidprivate.html Qt6 has a lot of changes. Do not expect everything is the same.

I solved this deployment issue after following solution from this post: https://forum.qt.io/topic/140996/qt-6-4-1-android-installing-the-app-failed-with-an-unknown-error

Hi and welcome to devnet, Boot2Qt being a commercial product, you should contact the Qt Company. That said, I would check that you have all the required libraries and plugins installed on your device.

Hi and welcome to devnet, Did you already went through the Qt for Androïd Getting Started guide ?

Ah that makes sense. Thanks @patrickkidd

@jsulm Thanks for the feedback. I think that at least Qt5.15 is required to supports Android 13 (see https://medium.com/@shmilysyg/set-android-target-sdk-level-33-in-qt-38bb9049924c). I prefer using Qt5.15.2 since I am using .pro files. Also, I suppose that I need higher JDK and NDK versions. While I do not think that the issue is related to the code (I tested Qt example and did not work), here is my formatted code: void MainWindow::deviceDiscovered(const QBluetoothDeviceInfo &device) { qDebug() << "[BLE] Raw: " << device.name() << device.address().toString(); if(device.coreConfigurations()&QBluetoothDeviceInfo::LowEnergyCoreConfiguration) { qDebug() << "Discovered:" << device.name() << device.address().toString(); if(BLE_liste->findItems(device.name()+"\n"+device.address().toString(),Qt::MatchExactly).count()==0) { BLE_liste->addItem(device.name()+"\n"+device.address().toString()); *dev_info=device; QBluetoothDeviceInfo* temp_info=new QBluetoothDeviceInfo; *temp_info=device; dev_info_list.append(temp_info); } } } void MainWindow::searchCharacteristic() { if(BLE_service){ foreach (QLowEnergyCharacteristic c, BLE_service->characteristics()) { if(c.isValid()){ if (c.properties() & QLowEnergyCharacteristic::WriteNoResponse || c.properties() & QLowEnergyCharacteristic::Write) { m_writeCharacteristic = c; if(c.properties() & QLowEnergyCharacteristic::WriteNoResponse) m_writeMode = QLowEnergyService::WriteWithoutResponse; else m_writeMode = QLowEnergyService::WriteWithResponse; } if (c.properties() & QLowEnergyCharacteristic::Read) m_readCharacteristic = c; if(c.properties() & QLowEnergyCharacteristic::Notify) { m_notificationDesc = c.descriptor( QBluetoothUuid::ClientCharacteristicConfiguration); if (m_notificationDesc.isValid()) { BLE_service->writeDescriptor(m_notificationDesc, QByteArray::fromHex("0100")); } } } } } } void MainWindow::on_listWidget_itemClicked(QListWidgetItem *item) { string = item->text(); string = string.split("\n").at(0); //get the 1st word in string *dev_info=*(dev_info_list.at(BLE_liste->row(item))); BLE_controlleur=new QLowEnergyController(*dev_info,this); connect(BLE_controlleur, SIGNAL(connected()),this,SLOT(device_connected())); connect(BLE_controlleur, SIGNAL(discoveryFinished()),this,SLOT(service_discovered())); BLE_controlleur->connectToDevice(); } void MainWindow::device_connected() { BLE_controlleur->discoverServices(); } void MainWindow::service_discovered() { services_discovered=1; m_servicesUuid = BLE_controlleur->services(); int maxl=m_servicesUuid.length(); for(int i=0;i<maxl;i++) { if(m_servicesUuid.at(i).toString()=="{6e400001-b5a3-f393-e0a9-e50e24dcca9e}") { BLE_service= BLE_controlleur->createServiceObject(m_servicesUuid.at(i), this); connect(BLE_service, SIGNAL(stateChanged(QLowEnergyService::ServiceState)), this, SLOT(onServiceStateChanged(QLowEnergyService::ServiceState))); connect(BLE_service, SIGNAL(characteristicWritten(QLowEnergyCharacteristic,QByteArray)), this, SLOT(update_com_state_(QLowEnergyCharacteristic,QByteArray))); connect(BLE_service, SIGNAL(error(QLowEnergyService::ServiceError)), this, SLOT(error_slot(QLowEnergyService::ServiceError))); connect(Comm_timer, SIGNAL(timeout()),this, SLOT(update_com_state())); if(BLE_service->state() == QLowEnergyService::DiscoveryRequired) { BLE_service->discoverDetails(); } else searchCharacteristic(); BLE_liste->setStyleSheet("QListWidget{background-color: rgba(0,0,0,0);color:rgb(202,233,250);font-weight:bold;font-family:Myriad Pro Regular;font-size:64px;border:4px solid rgb(249,159,65);border-radius:12px;} QListWidget::item:selected{background:rgb(249,159,65);color:rgb(0,0,0);}"); } } } void MainWindow::onServiceStateChanged(QLowEnergyService::ServiceState s) { if (s == QLowEnergyService::ServiceDiscovered) { searchCharacteristic(); } } void MainWindow::BLE_search_slot() { if(agent!=nullptr) { delete agent; } if(ble_widget->isHidden()==false) { if(localDevice.hostMode()==QBluetoothLocalDevice::HostPoweredOff) {localDevice.powerOn(); QTimer::singleShot(2000, this, SLOT(BLE_search_slot())); } BLE_liste->clear(); dev_info_list.clear(); QtAndroid::requestPermissionsSync({ "android.permission.ACCESS_FINE_LOCATION", "android.permission.BLUETOOTH_SCAN", "android.permission.BLUETOOTH_CONNECT" }); agent = new QBluetoothDeviceDiscoveryAgent(); // create an object in ctors connect(agent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),this, SLOT(deviceDiscovered(QBluetoothDeviceInfo))); agent->start(QBluetoothDeviceDiscoveryAgent::LowEnergyMethod); } }

@LZHD OK, if supportedFeatures says exposure compensation is not supported then it will not work with Qt. What Qt version do you use?

Thanks @jsulm I'll give it a go immediately!

@kkgg said in how to open file ? qt for ios?: I don't need to access the contents of the album You're trying to open a file and for this your app needs permissions. Also consider what @J-Hilk wrote.

hey @Jacob-Chafin ! Did you ever make it work ?

Up! just need 4 more testers ;)

Any one know where this file can be found?

@SGaist Thank you, your answer helped me!

Interesting, I received complaints from some users that this happens with and Android app I developed. They experience a grey screen on Android 15 (Qt 6.8.3) on Pixel phones. I have not experienced this myself on Android 14 on a Samsung Galaxy S22.

Qt is very sensitive to the environment, and releases often contain bugs. The main conditions for successful assembly and debugging in my case: Android build-tool version: should be the latest, i.e. the maximum with which the build is successful. If the build is not successful, then the version should be downgraded. Android build platform SDK: should be the latest, i.e. the maximum, with which the build is successful. If the build is not successful, then you should downgrade the version (https://doc.qt.io/qt-6/android.html + select your Qt release on the page). By the way, on 04/02/2025, the application using API 35 is not built and you should select the previous API version (34). Android NDK must be exactly the one specified in the documentation for the Qt version used (https://doc.qt.io/qt-6/android.html + select your Qt release on the page). For example, for version Qt 6.8.3 and Qt creator version 16.0.0, successful building and debugging were provided by the following set of components: -build-tool version: 35.0.1 -build platform SDK: 34 or 33 -android NDK: 26.1.10909125 [image: 43d9a4f8-0edc-40c9-8c1b-a2ef980b3505.PNG] [image: 10b3d856-52fb-4088-8969-2115ba09579e.PNG]