优化

flutter_monisuo/lib/ui/pages/asset/transfer_page.dart

@@ -140,9 +140,11 @@ class _TransferPageState extends State<TransferPage> {
   void _setQuickAmount(double percent) {
     final available = double.tryParse(_availableBalance) ?? 0;
     final amount = available * percent;
-    _amountController.text = amount
-        .toStringAsFixed(8)
-        .replaceAll(RegExp(r'\.?0+$'), '');
+    // 向下截斷到2位小數，避免四捨五入超出餘額
+    _amountController.text =
+        ((amount * 100).truncateToDouble() / 100).toStringAsFixed(2);
+
+    // Trigger haptic feedback
     HapticFeedback.selectionClick();
   }
 

flutter_monisuo/lib/ui/pages/orders/fund_order_card.dart

@@ -88,6 +88,11 @@ class _FundOrderCard extends StatelessWidget {
     final isDeposit = order.type == 1;
     final statusColor = _getStatusColor(order.status, isDeposit);
 
+    // 已出款的提現訂單顯示到賬金額，其餘顯示應付金額
+    final displayAmount = (!isDeposit && order.status == 2 && order.receivableAmount != null)
+        ? order.receivableAmount
+        : order.amount;
+
     return ShadCard(
       padding: AppSpacing.cardPadding,
       child: Column(
@@ -97,7 +102,7 @@ class _FundOrderCard extends StatelessWidget {
             mainAxisAlignment: MainAxisAlignment.spaceBetween,
             children: [
               Text(
-                '${isDeposit ? '+' : '-'}${order.amount} USDT',
+                '${isDeposit ? '+' : '-'}$displayAmount USDT',
                 style: AppTextStyles.headlineMedium(context).copyWith(
                   color: statusColor,
                   fontWeight: FontWeight.w700,

flutter_monisuo/lib/ui/pages/orders/fund_orders_page.dart

@@ -340,7 +340,7 @@ class _FundOrdersPageState extends State<FundOrdersPage> {
           const SizedBox(height: AppSpacing.sm - AppSpacing.xs),
         ],
         if (order.fee != null && !order.isDeposit) ...[
-          _buildDetailRow('手續費', '${order.fee}%'),
+          _buildDetailRow('手續費', '${order.fee} USDT'),
           const SizedBox(height: AppSpacing.sm - AppSpacing.xs),
         ],
         _buildDetailRow(
@@ -400,7 +400,7 @@ class _FundOrdersPageState extends State<FundOrdersPage> {
       child: Row(
         mainAxisAlignment: MainAxisAlignment.spaceBetween,
         children: [
-          Text('應付金額', style: AppTextStyles.headlineSmall(context).copyWith(color: context.colors.onSurfaceVariant)),
+          Text(order.status == 2 ? '到賬金額' : '應付金額', style: AppTextStyles.headlineSmall(context).copyWith(color: context.colors.onSurfaceVariant)),
           Text('${order.receivableAmount} USDT', style: AppTextStyles.headlineMedium(context).copyWith(color: context.colors.onSurface)),
         ],
       ),

flutter_monisuo/lib/ui/pages/trade/trade_page.dart

@@ -97,19 +97,27 @@ class _TradePageState extends State<TradePage>
     if (_tradeType == 0) {
       return _availableUsdt;
     } else {
+      // 賣出：qty * price 截斷到2位
       final qty = double.tryParse(_availableCoinQty) ?? 0;
-      return (qty * price).toStringAsFixed(2);
+      return ((qty * price * 100).truncateToDouble() / 100).toStringAsFixed(2);
     }
   }
 
-  /// 計算數量
+  /// 計算數量（向下截斷到4位小數，確保 price * quantity <= amount）
   String get _calculatedQuantity {
     final amount = double.tryParse(_amountController.text) ?? 0;
     final price = _selectedCoin?.price ?? 0;
     if (price <= 0 || amount <= 0) return '0';
-    // 向下截斷到4位小數，避免回算超出金額
-    final qty = amount / price;
-    return ((qty * 10000).truncateToDouble() / 10000).toStringAsFixed(4);
+    // 使用與後端一致的截斷邏輯：先算原始數量，截斷到4位，再回算金額確保不超
+    final rawQty = amount / price;
+    final truncatedQty = (rawQty * 10000).truncateToDouble() / 10000;
+    // 回算：roundedPrice * truncatedQty，確保不超過 amount
+    final roundedPrice = (price * 100).truncateToDouble() / 100;
+    if (roundedPrice * truncatedQty > amount) {
+      // 回退一個最小單位（0.0001）
+      return (truncatedQty - 0.0001).toStringAsFixed(4);
+    }
+    return truncatedQty.toStringAsFixed(4);
   }
 
   @override
@@ -208,11 +216,16 @@ class _TradePageState extends State<TradePage>
   void _fillPercent(double pct) {
     final max = double.tryParse(_maxAmount) ?? 0;
     final value = max * pct;
-    // 向下截斷到2位小數，避免四捨五入超出可用餘額
-    // 向下截斷到2位小數，再減0.01作為安全緩衝，避免精度問題導致餘額不足
-    final truncated = ((value * 100).truncateToDouble() / 100);
-    final safe = truncated > 0.01 ? truncated - 0.01 : truncated;
-    _amountController.text = safe.toStringAsFixed(2);
+
+    if (_tradeType == 0) {
+      // 買入：向下截斷到2位小數
+      _amountController.text =
+          ((value * 100).truncateToDouble() / 100).toStringAsFixed(2);
+    } else {
+      // 賣出：_maxAmount 已是 qty*price 的四捨五入值，直接截斷
+      _amountController.text =
+          ((value * 100).truncateToDouble() / 100).toStringAsFixed(2);
+    }
     setState(() {});
   }