Hi,

I created an app, that prints a label from an Android device on a Zebra Printer using Bluetooth. It works fine when debuging app but when I create a release apk file and install it on the device, the app crashes when trying to get ZebraPrinterLinkOs object, which I need to set the label length. This is the code I use for that:

Connection thePrinterConn = new BluetoothConnectionInsecure(printerMacAddress);

Looper.prepare();

thePrinterConn.open();

ZebraPrinterLinkOs linkOsPrinter = ZebraPrinterFactory.getLinkOsPrinter(thePrinterConn);

linkOsPrinter.setSetting("zpl.label_length", labelLength);

Because the issue occurs only in release build and the app itself is created using Flutter and not native Android, I have very limited logs from the moment of the crash. But what I have is:

E/AndroidRuntime(11406): FATAL EXCEPTION: Thread-6 E/AndroidRuntime(11406): Process: [app_package_name], PID: 11406 E/AndroidRuntime(11406): java.lang.ExceptionInInitializerError E/AndroidRuntime(11406):        at a3.s.<clinit>(SourceFile:16) E/AndroidRuntime(11406):        at com.google.android.gms.internal.mlkit_vision_barcode_bundled.c.b(SourceFile:1) E/AndroidRuntime(11406):        at q6.a.c(SourceFile:81) E/AndroidRuntime(11406):        at n3.o.m(SourceFile:111) E/AndroidRuntime(11406):        at n3.o.i(SourceFile:32) E/AndroidRuntime(11406):        at t2.a.run(SourceFile:27) E/AndroidRuntime(11406):        at java.lang.Thread.run(Thread.java:1012) E/AndroidRuntime(11406): Caused by: java.lang.NullPointerException: Attempt to invoke interface method 'u2.f u2.g.getterVisibility()' on a null object reference E/AndroidRuntime(11406):        at i3.u.<init>(SourceFile:2) E/AndroidRuntime(11406):        at i3.u.<clinit>(SourceFile:1) E/AndroidRuntime(11406):        ... 7 more

Because it works in debug build I cannot think about anything I can do to fix it. Unless there is some configuration that needs to be done specifically for release but it's not mentioned in the official docs.