fix: stable pairing code cells and numpad focus

Author: ovitrif

app/src/main/java/to/bitkit/ui/components/NumberPad.kt

@@ -38,6 +38,7 @@ import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import kotlinx.coroutines.delay
 import to.bitkit.R
 import to.bitkit.models.BitcoinDisplayUnit
 import to.bitkit.models.PrimaryDisplay
@@ -50,11 +51,14 @@ import to.bitkit.ui.theme.Colors
 import to.bitkit.viewmodels.AmountInputViewModel
 import to.bitkit.viewmodels.previewAmountInputViewModel
 import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
 
 const val KEY_DELETE = "delete"
 const val KEY_000 = "000"
 const val KEY_DECIMAL = "."
 private val defaultHeight = 300.dp
+private const val FOCUS_RETRY_COUNT = 10
+private val FOCUS_RETRY_DELAY = 50.milliseconds
 private val idealButtonHeight = 75.dp
 private val minButtonHeight = 50.dp
 private const val ROWS = 4
@@ -78,7 +82,14 @@ fun NumberPad(
     onDeleteLongPress: (() -> Unit)? = null,
 ) {
     val focusRequester = remember { FocusRequester() }
-    LaunchedEffect(Unit) { focusRequester.requestFocus() }
+    LaunchedEffect(Unit) {
+        // Composing mid sheet/nav transition can drop the initial request, leaving
+        // hardware keyboard input dead; retry briefly until the focus node takes it.
+        repeat(FOCUS_RETRY_COUNT) {
+            if (runCatching { focusRequester.requestFocus() }.isSuccess) return@LaunchedEffect
+            delay(FOCUS_RETRY_DELAY)
+        }
+    }
     val safeAreaModifier = if (includeNavigationBarsPadding) {
         modifier.navigationBarsPadding()
     } else {

app/src/main/java/to/bitkit/ui/sheets/HardwareSheet.kt

@@ -2,6 +2,7 @@ package to.bitkit.ui.sheets
 
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
@@ -11,6 +12,7 @@ import androidx.compose.foundation.layout.navigationBarsPadding
 import androidx.compose.foundation.layout.offset
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.DisposableEffect
 import androidx.compose.runtime.getValue
@@ -22,9 +24,6 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
-import androidx.compose.ui.text.SpanStyle
-import androidx.compose.ui.text.buildAnnotatedString
-import androidx.compose.ui.text.withStyle
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.navigation.compose.NavHost
@@ -173,14 +172,21 @@ private fun HardwarePairing(
         ) {
             BodyM(stringResource(R.string.hardware__pairing_text), color = Colors.White64)
             FillHeight()
-            Display(
-                buildAnnotatedString {
-                    append(code)
-                    withStyle(SpanStyle(color = Colors.White32)) {
-                        repeat(PAIRING_CODE_LENGTH - code.length) { append('•') }
+            // Fixed-width cells so digits replace dots without the row shifting.
+            Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                repeat(PAIRING_CODE_LENGTH) { index ->
+                    val digit = code.getOrNull(index)?.toString()
+                    Box(
+                        contentAlignment = Alignment.Center,
+                        modifier = Modifier.width(PAIRING_CELL_WIDTH)
+                    ) {
+                        Display(
+                            text = digit ?: "•",
+                            color = if (digit != null) Colors.White else Colors.White32,
+                        )
                     }
                 }
-            )
+            }
             FillHeight()
         }
         NumberPad(
@@ -210,6 +216,7 @@ sealed interface HardwareRoute {
 }
 
 private const val PAIRING_CODE_LENGTH = 6
+private val PAIRING_CELL_WIDTH = 32.dp
 
 // Proportions taken from the 375dp-wide Figma frame: 256dp visuals bleeding
 // 84dp off the left edge and 53dp off the right, staggered by 12dp vertically.