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Qt 5.5.1 Android 5.0.1 Bluetooth Low Energy Example won´t work

  • I`ve encountered a problem with one of the Qt examples (lowenergyscanner) regarding Android 5.0.1 running on a Galaxy S4 Active.

    I`ve previously complied the example with sdk level 26 (the level doesn´t matter in this regard -> just for information) for android 4.4.2 on the same phone mentioned before. The example runs perfectly and I can discover devices, connect to them, discover the services and charateristics. So far so good.

    But under Android 5.0.1:
    The example work´s until the point where QLowEnergyService->discoverDetails() is called. After that the signal QLowEnergyService stateChanged() is emitted one time with the state QLowEnergyService::DiscoveringServices and then the Android Gatt server is reporting this:
    W/QtBluetoothGatt(16138): onCharacteristicRead error: 133

    After that nothing happens. Even the QLowEnergyService error() isn`t emitted!

    I haven`t found anything regarding this problem in this specific combination. Is Qt 5.5.1 not working proberly with Android 5.0.1??

  • I know this question is old, but it seems noone is answering BLE related questions here. (I've just posted such a question myself, and fear noone will anwer it either).

    I developed an app based on the same example, and it worked fine under both android 4.3.2, 5.1.2, and 6.0. However, the customer came with an android 5.01, and sure enough, the app did not work as expected. It seemed to "hang" and tried to connect to two devices at the same time, etc. We did not investigate it further. This was with Qt 5.6, so the issue is not resolved, and may never be, since with newer versions of Android it is working fine.