IEnumerable == and Equals changes - #fixes 309 - MvvmCross#309

Costo · Jul 5, 2013 · ccfc44b · ccfc44b
1 parent 9fc394f
commit ccfc44b
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Showing 2 changed files with 29 additions and 5 deletions.
diff --git a/Cirrious/Cirrious.MvvmCross.Binding.Droid/Target/MvxSpinnerSelectedItemBinding.cs b/Cirrious/Cirrious.MvvmCross.Binding.Droid/Target/MvxSpinnerSelectedItemBinding.cs
@@ -35,11 +35,23 @@ private void SpinnerItemSelected(object sender, AdapterView.ItemSelectedEventArg
 
             var newValue = spinner.Adapter.GetRawItem(e.Position);
 
-            if (!newValue.Equals(_currentValue))
+            bool changed;
+            if (newValue == null)
             {
-                _currentValue = newValue;
-                FireValueChanged(newValue);
+                changed = (_currentValue != null);
             }
+            else
+            {
+                changed = !(newValue.Equals(_currentValue));
+            }
+
+            if (!changed)
+            {
+                return;
+            }
+
+            _currentValue = newValue;
+            FireValueChanged(newValue);            
         }
 
         public override void SetValue(object value)
@@ -48,7 +60,13 @@ public override void SetValue(object value)
             if (spinner == null)
                 return;
 
-            if (value != null && !value.Equals(_currentValue))
+            if (value == null)
+            {
+                MvxBindingTrace.Warning("Null values not permitted in spinner SelectedItem binding currently");
+                return;
+            }
+
+            if (!value.Equals(_currentValue))
             {
                 var index = spinner.Adapter.GetPosition(value);
                 if (index < 0)

diff --git a/Cirrious/Cirrious.MvvmCross.Binding/ExtensionMethods/MvxEnumerableExtensions.cs b/Cirrious/Cirrious.MvvmCross.Binding/ExtensionMethods/MvxEnumerableExtensions.cs
@@ -55,7 +55,13 @@ public static int GetPosition(this IEnumerable items, object item)
                     return -1;
                 }
 
-                if (enumerator.Current == item)
+                if (enumerator.Current == null)
+                {
+                    if (item == null)
+                        return i;
+                }
+                // Note: do *not* use == here - see https://github.com/slodge/MvvmCross/issues/309
+                else if (enumerator.Current.Equals(item))
                 {
                     return i;
                 }