Updated on 2026-08-14

app/src/main/java/com/tangem/tap/common/text/DecimalDigitsInputFilter.kt

@@ -10,9 +10,9 @@ import java.util.regex.Pattern
 class DecimalDigitsInputFilter(
         digitsBeforeDecimal: Int,
         digitsAfterDecimal: Int,
-        decimalSeparator: String
+        private val decimalSeparator: String
 ) : InputFilter {
-    private val pattern: Pattern = Pattern.compile("(([1-9]{1}[0-9]{0,${digitsBeforeDecimal -1}})?||[0]{1})((\\$decimalSeparator[0-9]{0,$digitsAfterDecimal})?)||(\\$decimalSeparator)?")
+    private val pattern: Pattern = Pattern.compile("(([1-9]{1}[0-9]{0,${digitsBeforeDecimal - 1}})?||[0]{1})((\\$decimalSeparator[0-9]{0,$digitsAfterDecimal})?)||(\\$decimalSeparator)?")
 
     override fun filter(source: CharSequence, sourceStart: Int, sourceEnd: Int, destination: Spanned, destinationStart: Int, destinationEnd: Int): CharSequence? {
         val destString = destination.toString()
@@ -24,7 +24,27 @@ class DecimalDigitsInputFilter(
         val resultSuffix = newDestination.substring(destinationStart, newDestination.length)
         val result = resultPrefix + source.toString() + resultSuffix
 
-        val hasMatches = pattern.matcher(result).matches()
-        return if (hasMatches) null else ""
+        return if (pattern.matcher(result).matches()) {
+            null
+        } else {
+            val replacedWithAppropriateDecimalSeparator = setDecimalSeparator(result, decimalSeparator)
+            if (pattern.matcher(replacedWithAppropriateDecimalSeparator).matches()) {
+                decimalSeparator
+            } else {
+                ""
+            }
+        }
     }
-}
+
+    companion object {
+        fun setDecimalSeparator(value: String, decimalSeparator: String): String {
+            if (value.contains(decimalSeparator)) return value
+
+            return if (decimalSeparator == ".") {
+                value.replace(",", decimalSeparator)
+            } else {
+                value.replace(".", decimalSeparator)
+            }
+        }
+    }
+}

app/src/main/java/com/tangem/tap/features/send/redux/states/SendState.kt

@@ -6,6 +6,7 @@ import com.tangem.blockchain.common.WalletManager
 import com.tangem.common.extensions.isZero
 import com.tangem.tap.common.CurrencyConverter
 import com.tangem.tap.common.entities.TapCurrency
+import com.tangem.tap.common.text.DecimalDigitsInputFilter
 import com.tangem.tap.domain.TapError
 import com.tangem.tap.store
 import org.rekotlin.StateType
@@ -143,13 +144,7 @@ data class AmountState(
     }
 
     fun restoreDecimalSeparator(value: String): String {
-        if (value.contains(decimalSeparator)) return value
-
-        return if (decimalSeparator == ".") {
-            value.replace(",", decimalSeparator)
-        } else {
-            value.replace(".", decimalSeparator)
-        }
+        return DecimalDigitsInputFilter.setDecimalSeparator(value, decimalSeparator)
     }
 }
 

app/src/main/java/com/tangem/tap/features/send/ui/SendFragment.kt

@@ -144,7 +144,7 @@ class SendFragment : BaseStoreFragment(R.layout.fragment_send) {
             }
         }
 
-        etAmountToSend.keyListener = DigitsKeyListener.getInstance("0123456789$decimalSeparator")
+        etAmountToSend.keyListener = DigitsKeyListener.getInstance("0123456789,.")
         etAmountToSend.setOnFocusChangeListener { v, hasFocus ->
             snackbarControlledByChangingFocus = true
             if (hasFocus) {