fix(android): transfer flow improvements and message_hash format fix

Transfer Screen improvements:
- Add QR code scanning for recipient address (using zxing library)
- Support EIP-681 URI format (ethereum:0x...) and plain address
- Remove password requirement - TSS wallets don't need passwords
- Remove unused onScanQrCode callback parameter

WalletsScreen changes:
- Simplify onTransfer callback to only pass shareId
- Remove TransferDialog - now navigates directly to TransferScreen
- Remove unused state variables (showTransferDialog, transferWallet)

Bug fix:
- Remove 0x prefix from message_hash before sending to API
- Backend expects pure hex, not 0x-prefixed hex string

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/MainActivity.kt

@@ -170,9 +170,8 @@ fun TssPartyApp(
                     networkType = settings.networkType,
                     onDeleteShare = { viewModel.deleteShare(it) },
                     onRefreshBalance = { address -> viewModel.fetchBalance(address) },
-                    onTransfer = { shareId, toAddress, amount, password ->
+                    onTransfer = { shareId ->
                         transferWalletId = shareId
-                        viewModel.prepareTransfer(shareId, toAddress, amount)
                         navController.navigate("transfer/$shareId")
                     },
                     onCreateWallet = {
@@ -209,9 +208,6 @@ fun TssPartyApp(
                         onConfirmTransaction = {
                             viewModel.initiateSignSession(shareId, "")
                         },
-                        onScanQrCode = {
-                            // TODO: Launch QR scanner for recipient address
-                        },
                         onCopyInviteCode = {
                             signInviteCode?.let { onCopyToClipboard(it) }
                         },

backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/data/repository/TssRepository.kt

@@ -1697,10 +1697,16 @@ class TssRepository @Inject constructor(
                 // Build request body matching account-service API
                 // Note: Android ShareRecordEntity doesn't store wallet_name, use address-based name
                 val walletName = "Wallet ${shareEntity.address.take(8)}...${shareEntity.address.takeLast(4)}"
+                // Remove 0x prefix from messageHash - backend expects pure hex
+                val cleanMessageHash = if (messageHash.startsWith("0x") || messageHash.startsWith("0X")) {
+                    messageHash.substring(2)
+                } else {
+                    messageHash
+                }
                 val requestBody = com.google.gson.JsonObject().apply {
                     addProperty("keygen_session_id", shareEntity.sessionId)
                     addProperty("wallet_name", walletName)
-                    addProperty("message_hash", messageHash)
+                    addProperty("message_hash", cleanMessageHash)
                     add("parties", partiesArray)
                     addProperty("threshold_t", shareEntity.thresholdT)
                     addProperty("initiator_name", initiatorName)

backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/screens/TransferScreen.kt

@@ -27,6 +27,8 @@ import com.durian.tssparty.domain.model.NetworkType
 import com.durian.tssparty.domain.model.SessionStatus
 import com.durian.tssparty.domain.model.ShareRecord
 import com.durian.tssparty.util.TransactionUtils
+import com.journeyapps.barcodescanner.ScanContract
+import com.journeyapps.barcodescanner.ScanOptions
 import kotlinx.coroutines.launch
 import java.math.BigInteger
 
@@ -34,13 +36,15 @@ import java.math.BigInteger
  * Transfer Screen - matches service-party-app Home.tsx transfer flow exactly
  *
  * Flow:
- * 1. input - Enter recipient address, amount, password
+ * 1. input - Enter recipient address and amount (QR scan or manual input)
  * 2. preparing - Preparing transaction (getting nonce, gas, etc.)
  * 3. confirm - Confirm transaction details with gas fees
  * 4. signing - TSS multi-party signing in progress
  * 5. broadcasting - Broadcasting signed transaction
  * 6. completed - Show transaction hash and explorer link
  * 7. error - Show error message
+ *
+ * Note: No password required - TSS wallets don't use passwords
  */
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -65,13 +69,31 @@ fun TransferScreen(
     onCopyInviteCode: () -> Unit,
     onBroadcastTransaction: () -> Unit,
     onCancel: () -> Unit,
-    onBackToWallets: () -> Unit,
+    onBackToWallets: () -> Unit
-    onScanQrCode: () -> Unit = {}
 ) {
     var toAddress by remember { mutableStateOf("") }
     var amount by remember { mutableStateOf("") }
     var validationError by remember { mutableStateOf<String?>(null) }
 
+    // QR Scanner launcher for recipient address
+    val scanLauncher = rememberLauncherForActivityResult(ScanContract()) { result ->
+        result.contents?.let { scannedContent ->
+            // Handle scanned address - may be plain address or EIP-681 URI
+            val address = if (scannedContent.startsWith("ethereum:")) {
+                // Parse EIP-681 URI: ethereum:0x...[@chainId][/function]?[params]
+                scannedContent.removePrefix("ethereum:").split("@", "/", "?").firstOrNull() ?: scannedContent
+            } else {
+                scannedContent
+            }
+            // Only set if it looks like a valid address
+            if (address.startsWith("0x") && address.length == 42) {
+                toAddress = address
+            } else {
+                validationError = "扫描的不是有效的钱包地址"
+            }
+        }
+    }
+
     // Determine current step
     val step = when {
         txHash != null -> "completed"
@@ -132,7 +154,18 @@ fun TransferScreen(
                     }
                 },
                 onCancel = onCancel,
-                onScanQrCode = onScanQrCode
+                onScanQrCode = {
+                    val options = ScanOptions().apply {
+                        setDesiredBarcodeFormats(ScanOptions.QR_CODE)
+                        setPrompt("扫描收款地址二维码")
+                        setCameraId(0)
+                        setBeepEnabled(true)
+                        setBarcodeImageEnabled(false)
+                        setOrientationLocked(true)
+                        setCaptureActivity(PortraitCaptureActivity::class.java)
+                    }
+                    scanLauncher.launch(options)
+                }
             )
 
             "preparing" -> PreparingScreen()

backend/mpc-system/services/service-party-android/app/src/main/java/com/durian/tssparty/presentation/screens/WalletsScreen.kt

@@ -27,6 +27,7 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.text.input.PasswordVisualTransformation
 import androidx.compose.ui.text.input.VisualTransformation
+// Note: Some unused imports kept for ExportBackupDialog which still uses password
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
@@ -50,13 +51,11 @@ fun WalletsScreen(
     networkType: NetworkType = NetworkType.MAINNET,
     onDeleteShare: (Long) -> Unit,
     onRefreshBalance: ((String) -> Unit)? = null,
-    onTransfer: ((shareId: Long, toAddress: String, amount: String, password: String) -> Unit)? = null,
+    onTransfer: ((shareId: Long) -> Unit)? = null,
     onExportBackup: ((shareId: Long, password: String) -> Unit)? = null,
     onCreateWallet: (() -> Unit)? = null
 ) {
     var selectedWallet by remember { mutableStateOf<ShareRecord?>(null) }
-    var showTransferDialog by remember { mutableStateOf(false) }
-    var transferWallet by remember { mutableStateOf<ShareRecord?>(null) }
 
     Box(modifier = Modifier.fillMaxSize()) {
         Column(
@@ -149,8 +148,7 @@ fun WalletsScreen(
                         balance = balances[share.address],
                         onViewDetails = { selectedWallet = share },
                         onTransfer = {
-                            transferWallet = share
+                            onTransfer?.invoke(share.id)
-                            showTransferDialog = true
                         },
                         onDelete = { onDeleteShare(share.id) }
                     )
@@ -185,30 +183,13 @@ fun WalletsScreen(
             onDismiss = { selectedWallet = null },
             onTransfer = {
                 selectedWallet = null
-                transferWallet = wallet
+                onTransfer?.invoke(wallet.id)
-                showTransferDialog = true
             },
             onExport = onExportBackup?.let { export ->
                 { password -> export(wallet.id, password) }
             }
         )
     }
-
-    // Transfer dialog
-    if (showTransferDialog && transferWallet != null) {
-        TransferDialog(
-            wallet = transferWallet!!,
-            onDismiss = {
-                showTransferDialog = false
-                transferWallet = null
-            },
-            onConfirm = { toAddress, amount, password ->
-                onTransfer?.invoke(transferWallet!!.id, toAddress, amount, password)
-                showTransferDialog = false
-                transferWallet = null
-            }
-        )
-    }
 }
 
 @Composable
@@ -604,178 +585,6 @@ private fun InfoRow(label: String, value: String) {
     }
 }
 
-@Composable
-private fun TransferDialog(
-    wallet: ShareRecord,
-    onDismiss: () -> Unit,
-    onConfirm: (toAddress: String, amount: String, password: String) -> Unit
-) {
-    var toAddress by remember { mutableStateOf("") }
-    var amount by remember { mutableStateOf("") }
-    var password by remember { mutableStateOf("") }
-    var showPassword by remember { mutableStateOf(false) }
-    var error by remember { mutableStateOf<String?>(null) }
-
-    Dialog(onDismissRequest = onDismiss) {
-        Card(
-            modifier = Modifier
-                .fillMaxWidth()
-                .padding(16.dp),
-            shape = RoundedCornerShape(16.dp)
-        ) {
-            Column(
-                modifier = Modifier
-                    .verticalScroll(rememberScrollState())
-                    .padding(24.dp)
-            ) {
-                Text(
-                    text = "转账",
-                    style = MaterialTheme.typography.headlineSmall,
-                    fontWeight = FontWeight.Bold
-                )
-
-                Spacer(modifier = Modifier.height(8.dp))
-
-                Text(
-                    text = "从 ${wallet.address.take(10)}...${wallet.address.takeLast(8)}",
-                    style = MaterialTheme.typography.bodySmall,
-                    color = MaterialTheme.colorScheme.outline
-                )
-
-                Spacer(modifier = Modifier.height(24.dp))
-
-                // Recipient address
-                OutlinedTextField(
-                    value = toAddress,
-                    onValueChange = { toAddress = it },
-                    label = { Text("收款地址") },
-                    placeholder = { Text("0x...") },
-                    modifier = Modifier.fillMaxWidth(),
-                    singleLine = true,
-                    leadingIcon = {
-                        Icon(Icons.Default.Person, contentDescription = null)
-                    }
-                )
-
-                Spacer(modifier = Modifier.height(16.dp))
-
-                // Amount
-                OutlinedTextField(
-                    value = amount,
-                    onValueChange = { amount = it },
-                    label = { Text("金额 (KAVA)") },
-                    placeholder = { Text("0.0") },
-                    modifier = Modifier.fillMaxWidth(),
-                    singleLine = true,
-                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Decimal),
-                    leadingIcon = {
-                        Icon(Icons.Default.AttachMoney, contentDescription = null)
-                    }
-                )
-
-                Spacer(modifier = Modifier.height(16.dp))
-
-                // Password
-                OutlinedTextField(
-                    value = password,
-                    onValueChange = { password = it },
-                    label = { Text("钱包密码") },
-                    modifier = Modifier.fillMaxWidth(),
-                    singleLine = true,
-                    visualTransformation = if (showPassword) VisualTransformation.None else PasswordVisualTransformation(),
-                    leadingIcon = {
-                        Icon(Icons.Default.Lock, contentDescription = null)
-                    },
-                    trailingIcon = {
-                        IconButton(onClick = { showPassword = !showPassword }) {
-                            Icon(
-                                if (showPassword) Icons.Default.VisibilityOff else Icons.Default.Visibility,
-                                contentDescription = null
-                            )
-                        }
-                    }
-                )
-
-                error?.let {
-                    Spacer(modifier = Modifier.height(8.dp))
-                    Text(
-                        text = it,
-                        color = MaterialTheme.colorScheme.error,
-                        style = MaterialTheme.typography.bodySmall
-                    )
-                }
-
-                Spacer(modifier = Modifier.height(16.dp))
-
-                // Info card
-                Card(
-                    colors = CardDefaults.cardColors(
-                        containerColor = MaterialTheme.colorScheme.secondaryContainer
-                    )
-                ) {
-                    Row(
-                        modifier = Modifier.padding(12.dp),
-                        verticalAlignment = Alignment.Top
-                    ) {
-                        Icon(
-                            Icons.Default.Info,
-                            contentDescription = null,
-                            modifier = Modifier.size(20.dp),
-                            tint = MaterialTheme.colorScheme.onSecondaryContainer
-                        )
-                        Spacer(modifier = Modifier.width(8.dp))
-                        Text(
-                            text = "转账需要 ${wallet.thresholdT} 个参与者共同签名。确认后将创建签名会话。",
-                            style = MaterialTheme.typography.bodySmall,
-                            color = MaterialTheme.colorScheme.onSecondaryContainer
-                        )
-                    }
-                }
-
-                Spacer(modifier = Modifier.height(24.dp))
-
-                // Buttons
-                Row(
-                    modifier = Modifier.fillMaxWidth(),
-                    horizontalArrangement = Arrangement.spacedBy(8.dp)
-                ) {
-                    OutlinedButton(
-                        onClick = onDismiss,
-                        modifier = Modifier.weight(1f)
-                    ) {
-                        Text("取消")
-                    }
-
-                    Button(
-                        onClick = {
-                            when {
-                                toAddress.isBlank() -> error = "请输入收款地址"
-                                !toAddress.startsWith("0x") || toAddress.length != 42 -> error = "地址格式不正确"
-                                amount.isBlank() -> error = "请输入金额"
-                                amount.toDoubleOrNull() == null || amount.toDouble() <= 0 -> error = "金额无效"
-                                password.isBlank() -> error = "请输入密码"
-                                else -> {
-                                    error = null
-                                    onConfirm(toAddress, amount, password)
-                                }
-                            }
-                        },
-                        modifier = Modifier.weight(1f)
-                    ) {
-                        Icon(
-                            Icons.Default.Send,
-                            contentDescription = null,
-                            modifier = Modifier.size(18.dp)
-                        )
-                        Spacer(modifier = Modifier.width(4.dp))
-                        Text("确认转账")
-                    }
-                }
-            }
-        }
-    }
-}
-
 @Composable
 private fun ExportBackupDialog(
     onDismiss: () -> Unit,