add map view page

Billing.Shared/Views/AddBillPage.xaml.cs

@@ -60,6 +60,7 @@ namespace Billing.Views
 
         public Command SelectCategory { get; }
         public Command SelectWallet { get; }
+        public Command ViewLocation { get; }
 
         public event EventHandler<Bill> BillChecked;
 
@@ -76,6 +77,7 @@ namespace Billing.Views
             createDate = date;
             SelectCategory = new Command(OnSelectCategory);
             SelectWallet = new Command(OnSelectWallet);
+            ViewLocation = new Command(() => { }, () => false);
             InitializeComponent();
             Title = Resource.AddBill;
 
@@ -86,7 +88,12 @@ namespace Billing.Views
         {
             this.bill = bill;
             SelectCategory = new Command(OnSelectCategory);
-            SelectWallet = new Command(OnSelectWallet);
+            SelectWallet = new Command(OnSelectWallet);
+#if __ANDROID__
+            ViewLocation = new Command(() => { }, () => false);
+#else
+            ViewLocation = new Command(OnViewLocation, () => bill != null && bill.Latitude != null && bill.Longitude != null);
+#endif
             InitializeComponent();
             Title = Resource.EditBill;
 
@@ -129,7 +136,7 @@ namespace Billing.Views
         {
             editorAmount.SetFocus();
 
-            if (App.SaveLocation)
+            if (bill == null && App.SaveLocation)
             {
                 _ = GetCurrentLocation();
             }
@@ -280,5 +287,22 @@ namespace Billing.Views
         {
             SetValue(WalletProperty, account);
         }
+
+        private async void OnViewLocation()
+        {
+            if (bill == null)
+            {
+                return;
+            }
+            if (Tap.IsBusy)
+            {
+                return;
+            }
+            using (Tap.Start())
+            {
+                var page = new ViewLocationPage(bill);
+                await Navigation.PushAsync(page);
+            }
+        }
     }
 }