Fixing recursive setting of source and target value when converters are used in both directions.

GalaSoft.MvvmLight/GalaSoft.MvvmLight.Platform (Android)/Helpers/BindingGeneric.cs

@@ -833,7 +833,9 @@ namespace GalaSoft.MvvmLight.Helpers
                     && _propertyTarget.IsAlive
                     && _propertyTarget.Target != null)
                 {
+                    _settingSourceToTarget = true;
                     SetTargetValue(value);
+                    _settingSourceToTarget = false;
                 }
 
                 if (_onSourceUpdate != null
@@ -1128,7 +1130,8 @@ namespace GalaSoft.MvvmLight.Helpers
                 && _propertyTarget.Target != null
                 && _propertySource != null
                 && _propertySource.IsAlive
-                && _propertySource.Target != null)
+                && _propertySource.Target != null
+                && !_settingTargetToSource)
             {
                 var valueLocal = GetSourceValue();
                 var targetValue = _targetProperty.GetValue(_propertyTarget.Target, null);
@@ -1140,7 +1143,9 @@ namespace GalaSoft.MvvmLight.Helpers
 
                 if (_targetProperty != null)
                 {
+                    _settingSourceToTarget = true;
                     SetTargetValue(valueLocal);
+                    _settingSourceToTarget = false;
                 }
             }
 
@@ -1159,7 +1164,8 @@ namespace GalaSoft.MvvmLight.Helpers
                 && _propertyTarget.Target != null
                 && _propertySource != null
                 && _propertySource.IsAlive
-                && _propertySource.Target != null)
+                && _propertySource.Target != null
+                && !_settingSourceToTarget)
             {
                 var valueLocal = GetTargetValue();
                 var sourceValue = _sourceProperty.GetValue(_propertySource.Target, null);
@@ -1169,7 +1175,9 @@ namespace GalaSoft.MvvmLight.Helpers
                     return;
                 }
 
+                _settingTargetToSource = true;
                 SetSourceValue(valueLocal);
+                _settingTargetToSource = false;
             }
 
             RaiseValueChanged();

GalaSoft.MvvmLight/Tests/AndroidTestApp/GalaSoft.MvvmLight.Test (Android).csproj

@@ -92,6 +92,7 @@
     <Compile Include="Binding\BindingTargetTest.cs" />
     <Compile Include="Binding\BindingSourceTest.cs" />
     <Compile Include="Binding\BindingTest.cs" />
+    <Compile Include="Binding\ConverterTest.cs" />
     <Compile Include="Binding\SetCommandTest.cs" />
     <Compile Include="Binding\ObserveEventImplicitTest.cs" />
     <Compile Include="Binding\ObserveEventLostFocusTest.cs" />

GalaSoft.MvvmLight/Tests/AndroidTestApp/ViewModel/TestViewModel.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Windows.Input;
 using GalaSoft.MvvmLight.Command;
 
@@ -6,6 +7,8 @@ namespace GalaSoft.MvvmLight.Test.ViewModel
     public class TestViewModel : ViewModelBase
     {
         public const string ValueForCommand = "Command value";
+
+        private DateTime _date;
         private TestModel _model;
         private TestViewModel _nested;
         private string _propertyValue;
@@ -13,6 +16,18 @@ namespace GalaSoft.MvvmLight.Test.ViewModel
         private RelayCommand _setPropertyWithoutValueCommand;
         private ICommand _testCommandImpl;
 
+        public DateTime Date
+        {
+            get
+            {
+                return _date;
+            }
+            set
+            {
+                Set(ref _date, value);
+            }
+        }
+
         public TestModel Model
         {
             get

GalaSoft.MvvmLight/Tests/AppleTestApp/GalaSoft.MvvmLight.Test (iOS).csproj

@@ -141,6 +141,9 @@
     <Compile Include="..\AndroidTestApp\Binding\BindingTest.cs">
       <Link>Binding\BindingTest.cs</Link>
     </Compile>
+    <Compile Include="..\AndroidTestApp\Binding\ConverterTest.cs">
+      <Link>Binding\ConverterTest.cs</Link>
+    </Compile>
     <Compile Include="..\AndroidTestApp\ViewModel\AccountModel.cs">
       <Link>ViewModel\AccountModel.cs</Link>
     </Compile>