9. Error Reference

The table below lists all known errors and symptoms, their most likely cause, and the recommended resolution. Match the exception class or symptom you see in logcat to the appropriate row.

Error Table

Error / Symptom	Likely Cause	Resolution
IllegalStateException	SDK not initialized	Call getInstance(context, config)
InflateException	ConstraintLayout missing	Add constraintlayout dependency
UnsupportedDevice	OEM not recognised	Use supported device (HorizonPay or Topwise)
Print callback: success=false	Printer overheated or out of paper	Check printer hardware
Key exchange: success=false	TMS unreachable or device not registered	Verify network connectivity and device registration on UNISWITCH TMS
SecurityException on location	Runtime location permission not granted	Request ACCESS_FINE_LOCATION and ACCESS_COARSE_LOCATION at runtime

IllegalStateException — SDK Not Initialized

⚠️

Symptom Any SDK method call throws IllegalStateException.

Cause

You called an SDK method before getInstance(), or after destroy() was called, causing the singleton to be null.

Resolution

val pos = OctopusTMS.getInstance(
    context = applicationContext,
    config  = OctopusTMS.Config(
        appName    = "MyApp",
        enableLogs = BuildConfig.DEBUG
    )
)

InflateException — ConstraintLayout Missing

⚠️

Symptom App crashes on startPayment() with android.view.InflateException: Error inflating class androidx.constraintlayout.widget.ConstraintLayout.

Resolution

// build.gradle.kts
dependencies {
    implementation("androidx.constraintlayout:constraintlayout:2.1.4")
}

UnsupportedDevice — OEM Not Recognised

⚠️

Symptom initialize() callback returns InitResult.UnsupportedDevice.

Cause

The SDK could not match the hardware to any supported OEM driver. This occurs when running on a device that is not HorizonPay or Topwise, or on an emulator.

Resolution

Use a supported OEM device. New device drivers are added in SDK updates without API changes — contact UNISWITCH for the latest SDK version if your device model is not yet supported.