Updated on 2026-08-14

app/src/main/java/com/tangem/presentation/activity/PinRequestActivity.kt

@@ -173,8 +173,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     override fun onPause() {
         super.onPause()
-        if (fingerprintHelper != null)
-            fingerprintHelper!!.cancel()
+        fingerprintHelper?.cancel()
 
         if (startFingerprintReaderTask != null) {
             startFingerprintReaderTask!!.cancel(true)
@@ -184,8 +183,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     override fun onStop() {
         super.onStop()
-        if (fingerprintHelper != null)
-            fingerprintHelper!!.cancel()
+        fingerprintHelper?.cancel()
 
         if (startFingerprintReaderTask != null) {
             startFingerprintReaderTask!!.cancel(true)
@@ -214,7 +212,7 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
 
     @TargetApi(Build.VERSION_CODES.M)
     override fun authenticationSucceeded(result: FingerprintManager.AuthenticationResult) {
-        LOG.i(TAG,"Authentication succeeded!")
+        LOG.i(TAG, "Authentication succeeded!")
         val cipher = result.cryptoObject.cipher
 
         if (mode == Mode.RequestNewPIN || mode == Mode.ConfirmNewPIN) {
@@ -242,34 +240,33 @@ class PinRequestActivity : AppCompatActivity(), NfcAdapter.ReaderCallback, Finge
         finish()
     }
 
-    @SuppressLint("SetTextI18n")
     private fun buttonClick(button: Button) {
-        tvPin!!.text = tvPin!!.text.toString() + button.text as String
+        tvPin.text = tvPin.text.toString() + button.text.toString()
     }
 
     @SuppressLint("NewApi")
     private fun testFingerPrintSettings(): Boolean {
-        LOG.i(TAG,"Testing Fingerprint Settings")
+        LOG.i(TAG, "Testing Fingerprint Settings")
 
         val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
         fingerprintManager = getSystemService(Context.FINGERPRINT_SERVICE) as FingerprintManager
 
         if (!keyguardManager.isKeyguardSecure) {
-            LOG.i(TAG,"User hasn't enabled Lock Screen")
+            LOG.i(TAG, "User hasn't enabled Lock Screen")
             return false
         }
 
         if (ActivityCompat.checkSelfPermission(this, Manifest.permission.USE_FINGERPRINT) != PackageManager.PERMISSION_GRANTED) {
-            LOG.i(TAG,"User hasn't granted permission to use Fingerprint")
+            LOG.i(TAG, "User hasn't granted permission to use Fingerprint")
             return false
         }
 
         if (!fingerprintManager!!.hasEnrolledFingerprints()) {
-            LOG.i(TAG,"User hasn't registered any fingerprints")
+            LOG.i(TAG, "User hasn't registered any fingerprints")
             return false
         }
 
-        LOG.i(TAG,"Fingerprint authentication is set.\n")
+        LOG.i(TAG, "Fingerprint authentication is set.\n")
 
         return true
     }

app/src/main/java/com/tangem/presentation/activity/PrepareTransactionActivity.kt

@@ -11,6 +11,7 @@ import android.text.Html
 import android.view.View
 import android.view.inputmethod.EditorInfo
 import android.view.inputmethod.InputMethodManager
+import android.widget.Toast
 import androidx.appcompat.app.AppCompatActivity
 import com.tangem.App
 import com.tangem.Constant
@@ -20,6 +21,7 @@ import com.tangem.domain.wallet.CoinEngineFactory
 import com.tangem.domain.wallet.TangemContext
 import com.tangem.tangemcard.android.nfc.NfcLifecycleObserver
 import com.tangem.tangemcard.android.reader.NfcManager
+import com.tangem.util.UtilHelper
 import com.tangem.wallet.R
 import kotlinx.android.synthetic.main.activity_prepare_transaction.*
 import java.io.IOException
@@ -89,8 +91,12 @@ class PrepareTransactionActivity : AppCompatActivity(), NfcAdapter.ReaderCallbac
         }
 
         btnVerify.setOnClickListener {
-            val engine1 = CoinEngineFactory.create(ctx)
+            if (!UtilHelper.isOnline(this)) {
+                Toast.makeText(this, R.string.no_connection, Toast.LENGTH_LONG).show()
+                return@setOnClickListener
+            }
 
+            val engine1 = CoinEngineFactory.create(ctx)
             val strAmount: String = etAmount.text.toString().replace(",", ".")
             val amount = engine1!!.convertToAmount(etAmount.text.toString(), tvCurrency.text.toString())
 

app/src/main/java/com/tangem/presentation/dialog/ShowQRCodeDialog.java

@@ -1,6 +1,5 @@
 package com.tangem.presentation.dialog;
 
-import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.DialogInterface;

app/src/main/java/com/tangem/util/UtilHelper.kt

@@ -1,6 +1,5 @@
 package com.tangem.util
 
-import android.app.Activity
 import android.content.Context
 import android.graphics.Bitmap
 import android.graphics.Color