disable cancel invoice in customer

lib/pages/invoice/invoice_info.dart

@@ -66,6 +66,7 @@ class _InvoiceInfoState extends State<InvoiceInfo> {
   @override
   Widget build(BuildContext context) {
     bool isCanceled = _invoice.status == invoice_cancel_status;
+    bool isPaid = _invoice.status == invoice_paid_status;
     var rateModel = Provider.of<ShipmentRateModel>(context);
     var rate = rateModel.rate;
 
@@ -182,7 +183,9 @@ class _InvoiceInfoState extends State<InvoiceInfo> {
               SizedBox(
                 height: 10,
               ),
-              isCanceled || widget.forCustomer ? Container() : cancelBtn,
+              isCanceled || isPaid || widget.forCustomer
+                  ? Container()
+                  : cancelBtn,
             ],
           ),
         ),

lib/pages/invoice/invoice_list_row.dart

@@ -141,6 +141,28 @@ class InvoiceListRow extends StatelessWidget {
                 builder: (context) =>
                     InvoiceInfo(invoice: invoice, forCustomer: forCustomer)));
           },
+        ),
+        CupertinoActionSheetAction(
+          child: Row(
+            children: <Widget>[
+              Padding(
+                padding: const EdgeInsets.only(left: 8.0),
+                child: Text(
+                  'Payments',
+                  style: TextStyle(fontSize: 16, color: Colors.black),
+                ),
+              ),
+            ],
+          ),
+          onPressed: () async {
+            //to go invoice info page
+            Navigator.pop(context);
+            Navigator.of(context).push(CupertinoPageRoute(
+                builder: (context) => PaymentPage(
+                      invoice: invoice,
+                      forCustomer: forCustomer,
+                    )));
+          },
         )
       ],
     );

lib/pages/invoice/payment/payment_page.dart

@@ -37,11 +37,13 @@ class _PaymentPageState extends State<PaymentPage> {
 
   bool isNew;
   File _file;
+  bool _hasBalance;
 
   @override
   void initState() {
     super.initState();
     _invoice = widget.invoice;
+    _hasBalance = widget.invoice.balance > 0;
     _loadInvoice();
   }
 
@@ -100,16 +102,18 @@ class _PaymentPageState extends State<PaymentPage> {
         body: ListView(
           padding: const EdgeInsets.all(10.0),
           children: <Widget>[
-            amountBox,
+            _hasBalance ? amountBox : Container(),
             SizedBox(height: 10),
-            Align(
+            _hasBalance
-              child: Padding(
+                ? Align(
-                padding: const EdgeInsets.all(8.0),
+                    child: Padding(
-                child: receiptFileBox,
+                      padding: const EdgeInsets.all(8.0),
-              ),
+                      child: receiptFileBox,
-              alignment: Alignment.centerLeft,
+                    ),
-            ),
+                    alignment: Alignment.centerLeft,
-            payBtnBox,
+                  )
+                : Container(),
+            _hasBalance ? payBtnBox : Container(),
             SizedBox(height: 15),
             LocalTitle(textKey: "pm.receipt"),
             Column(