tearing down event handlers on page disappears

src/App/Controls/DismissModalToolBarItem.cs

@@ -4,14 +4,13 @@ using Xamarin.Forms;
 
 namespace Bit.App.Controls
 {
-    public class DismissModalToolBarItem : ToolbarItem, IDisposable
+    public class DismissModalToolBarItem : ExtendedToolbarItem, IDisposable
     {
         private readonly ContentPage _page;
-        private readonly Action _cancelClickedAction;
 
         public DismissModalToolBarItem(ContentPage page, string text = null, Action cancelClickedAction = null)
+            : base(cancelClickedAction)
         {
-            _cancelClickedAction = cancelClickedAction;
             _page = page;
             // TODO: init and dispose events from pages
             InitEvents();
@@ -19,20 +18,10 @@ namespace Bit.App.Controls
             Priority = -1;
         }
 
-        private async void ClickedItem(object sender, EventArgs e)
+        protected async override void ClickedItem(object sender, EventArgs e)
         {
-            _cancelClickedAction?.Invoke();
+            base.ClickedItem(sender, e);
             await _page.Navigation.PopModalAsync();
         }
-
-        public void InitEvents()
-        {
-            Clicked += ClickedItem;
-        }
-
-        public void Dispose()
-        {
-            Clicked -= ClickedItem;
-        }
     }
 }

src/App/Controls/ExtendedToolbarItem.cs

@@ -0,0 +1,30 @@
+using System;
+using Xamarin.Forms;
+
+namespace Bit.App.Controls
+{
+    public class ExtendedToolbarItem : ToolbarItem, IDisposable
+    {
+        public ExtendedToolbarItem(Action clickAction = null)
+        {
+            ClickAction = clickAction;
+        }
+
+        public Action ClickAction { get; set; }
+
+        protected virtual void ClickedItem(object sender, EventArgs e)
+        {
+            ClickAction?.Invoke();
+        }
+
+        public void InitEvents()
+        {
+            Clicked += ClickedItem;
+        }
+
+        public void Dispose()
+        {
+            Clicked -= ClickedItem;
+        }
+    }
+}

src/App/Controls/VaultListViewCell.cs

@@ -6,21 +6,17 @@ namespace Bit.App.Controls
 {
     public class VaultListViewCell : LabeledDetailCell
     {
-        private Action<VaultListPageModel.Login> _moreClickedAction;
-
         public static readonly BindableProperty LoginParameterProperty = BindableProperty.Create(nameof(LoginParameter),
             typeof(VaultListPageModel.Login), typeof(VaultListViewCell), null);
 
         public VaultListViewCell(Action<VaultListPageModel.Login> moreClickedAction)
         {
-            _moreClickedAction = moreClickedAction;
-
             SetBinding(LoginParameterProperty, new Binding("."));
             Label.SetBinding<VaultListPageModel.Login>(Label.TextProperty, s => s.Name);
             Detail.SetBinding<VaultListPageModel.Login>(Label.TextProperty, s => s.Username);
 
             Button.Image = "more";
-            Button.Command = new Command(() => ShowMore());
+            Button.Command = new Command(() => moreClickedAction?.Invoke(LoginParameter));
             Button.BackgroundColor = Color.Transparent;
 
             BackgroundColor = Color.White;
@@ -31,10 +27,5 @@ namespace Bit.App.Controls
             get { return GetValue(LoginParameterProperty) as VaultListPageModel.Login; }
             set { SetValue(LoginParameterProperty, value); }
         }
-
-        private void ShowMore()
-        {
-            _moreClickedAction?.Invoke(LoginParameter);
-        }
     }
 }