App crashing when connecting to QN-Scale (Slimpal)

[rosscullen]

Describe the bug
When I try to connect in OpenScale App to the connected "QN-Scale" Bluetooth broadcast (by turning on the bluetooth icon within the overview page) and then standing on the scales, the app shows the ladybird crash icon and a copy of log is below.

To Reproduce
Reproduced with 2.5.3 (65)

Debug log
Build version: 2.5.3
Build date: 1981-01-01 01:01:02
Current date: 2025-01-11 22:55:44
Device: Samsung SM-G973F
OS version: Android 12 (SDK 31)

Stack trace:
java.lang.NullPointerException: no valid characteristic provided
at j$.util.Objects.requireNonNull(Unknown Source:5)
at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1224)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:303)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:291)
at com.health.openscale.core.bluetooth.BluetoothQNScale.onNextStep(BluetoothQNScale.java:111)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:610)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.resumeMachineState(BluetoothCommunication.java:210)
at com.health.openscale.core.bluetooth.BluetoothCommunication$1.onServicesDiscovered(BluetoothCommunication.java:464)
at com.welie.blessed.BluetoothPeripheral$1$1.run(BluetoothPeripheral.java:213)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:226)
at android.os.Looper.loop(Looper.java:313)
at android.app.ActivityThread.main(ActivityThread.java:8751)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1135)

[0ut1awStar]

Having similar issue with a Renpho ES-CS20M Scale:

Build version: 2.5.3
Build date: 1981-01-01 01:01:02
Current date: 2025-01-15 11:20:37
Device: Motorola moto g stylus 5G - 2023
OS version: Android 14 (SDK 34)

Stack trace:
java.lang.NullPointerException: no valid characteristic provided
at j$.util.Objects.requireNonNull(Unknown Source:5)
at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1224)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:303)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:291)
at com.health.openscale.core.bluetooth.BluetoothQNScale.onNextStep(BluetoothQNScale.java:111)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:610)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.resumeMachineState(BluetoothCommunication.java:210)
at com.health.openscale.core.bluetooth.BluetoothCommunication$1.onServicesDiscovered(BluetoothCommunication.java:464)
at com.welie.blessed.BluetoothPeripheral$1$1.run(BluetoothPeripheral.java:213)
at android.os.Handler.handleCallback(Handler.java:1000)
at android.os.Handler.dispatchMessage(Handler.java:104)
at android.os.Looper.loopOnce(Looper.java:242)
at android.os.Looper.loop(Looper.java:362)
at android.app.ActivityThread.main(ActivityThread.java:8448)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:552)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:992)

[Paanreis]

Hello,

Same issue with a Renpho ES-CS20M.

Build version: 2.5.3
Build date: 1981-01-01 01:01:02
Current date: 2025-01-16 19:42:00
Device: Fairphone FP4
OS version: Android 13 (SDK 33)

Stack trace:
java.lang.NullPointerException: no valid characteristic provided
at j$.util.Objects.requireNonNull(Unknown Source:5)
at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1224)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:303)
at com.health.openscale.core.bluetooth.BluetoothCommunication.writeBytes(BluetoothCommunication.java:291)
at com.health.openscale.core.bluetooth.BluetoothQNScale.onNextStep(BluetoothQNScale.java:111)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:610)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.nextMachineStep(BluetoothCommunication.java:612)
at com.health.openscale.core.bluetooth.BluetoothCommunication.resumeMachineState(BluetoothCommunication.java:210)
at com.health.openscale.core.bluetooth.BluetoothCommunication$1.onServicesDiscovered(BluetoothCommunication.java:464)
at com.welie.blessed.BluetoothPeripheral$1$1.run(BluetoothPeripheral.java:213)
at android.os.Handler.handleCallback(Handler.java:942)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7932)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:942)