openscale crashes when connecting to ES-CS20M

[fbievan]

Open scale crashes when connecting to ES-CS20M Which is listed as a supported scale here: https://github.com/oliexdev/openScale/wiki/Supported-scales-in-openScale

To Reproduce Steps to reproduce the behavior:

1. Connect to scale
2. Step on scale
3. It crashes when finishes

Reproduced with latest dev version: yep

Expected behavior It connects and logs the weight

Build version: 2.5.1 
Build date: 1981-01-01 01:01:02 
Current date: 2023-03-16 10:12:00 
Device: Google Pixel 4a 
OS version: Android 13 (SDK 33) 
 
Stack trace:  
java.lang.NullPointerException: no valid characteristic provided
	at java.util.Objects.requireNonNull(Objects.java:245)
	at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1229)
	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$1.run(BluetoothPeripheral.java:210)
	at android.os.Handler.handleCallback(Handler.java:942)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loopOnce(Looper.java:201)
	at android.os.Looper.loop(Looper.java:288)
	at android.app.ActivityThread.main(ActivityThread.java:7872)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Again in Dev version, no change

[mikeloeven]

Can confirm looks like I am getting the same error. TBH I bought that scale because it was listed as compatible so unsure if there may be a new HW/FW revision being sold under the same model number

[mikeloeven]

Going to post my stack trace here as well

Build version: 2.5.1 Build date: 1981-01-01 01:01:02 Current date: 2023-03-26 18:34:27 Device: Samsung SAMSUNG-SM-G870A OS version: Android 6.0.1 (SDK 23) Stack trace: java.lang.NullPointerException: no valid characteristic provided at java.util.Objects.requireNonNull(Objects.java:109) at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1229) 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$1.run(BluetoothPeripheral.java:210) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:158) at android.app.ActivityThread.main(ActivityThread.java:7224) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

[pravardhanreddy]

Having the same issue. Hopefully gets fixed. Posting my stacktrace incase it helps. Downloaded the app from F-droid

Build version: 2.5.1 
Build date: 1981-01-01 01:01:02 
Current date: 2023-04-06 23:46:05 
Device: Samsung SM-G991U 
OS version: Android 13 (SDK 33) 
 
Stack trace:  
java.lang.NullPointerException: no valid characteristic provided
	at java.util.Objects.requireNonNull(Objects.java:245)
	at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1229)
	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$1.run(BluetoothPeripheral.java:210)
	at android.os.Handler.handleCallback(Handler.java:942)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loopOnce(Looper.java:226)
	at android.os.Looper.loop(Looper.java:313)
	at android.app.ActivityThread.main(ActivityThread.java:8757)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:571)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1067)

[tjdett]

Same issue:

Build version: 2.5.1-pro 
Build date: 1981-01-01 01:01:02 
Current date: 2023-06-11 23:25:31 
Device: Google Pixel 7a 
OS version: Android 13 (SDK 33) 
 
Stack trace:  
java.lang.NullPointerException: no valid characteristic provided
	at java.util.Objects.requireNonNull(Objects.java:245)
	at com.welie.blessed.BluetoothPeripheral.writeCharacteristic(BluetoothPeripheral.java:1229)
	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$1.run(BluetoothPeripheral.java:210)
	at android.os.Handler.handleCallback(Handler.java:942)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loopOnce(Looper.java:201)
	at android.os.Looper.loop(Looper.java:288)
	at android.app.ActivityThread.main(ActivityThread.java:7884)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Like @mikeloeven, bought the scale because it's listed as compatible. It identifies as QN-Scale in Bluetooth.

Here's the hardware info on the back of the scale in case it's useful:

[mikeloeven]

Can we please get some kind of acknowledgment that this issue is being worked on if the scale is no longer compatible then please at least remove it from your compatibility list but this was reported many months ago and there has not been a single comment from the developers Regarding why this is occurring

[MattCairns]

Any updates on this? I also bought your scale specially because it was listed as supported