Update (master): Fix selection pas beau

src/BookApp/Composants/GroupCollection.xaml

@@ -3,6 +3,23 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
              xmlns:composants="clr-namespace:BookApp.Composants"
              x:Class="BookApp.Composants.GroupCollection">
+    <ContentView.Resources>
+        <Style TargetType="StackLayout">
+            <Setter Property="VisualStateManager.VisualStateGroups">
+                <VisualStateGroupList>
+                    <VisualStateGroup x:Name="CommonStates">
+                        <VisualState x:Name="Normal" />
+                        <VisualState x:Name="Selected">
+                            <VisualState.Setters>
+                                <Setter Property="BackgroundColor"
+                                        Value="Transparent" />
+                            </VisualState.Setters>
+                        </VisualState>
+                    </VisualStateGroup>
+                </VisualStateGroupList>
+            </Setter>
+        </Style>
+    </ContentView.Resources>
     <CollectionView ItemsSource="{Binding AuteurGroups}" IsGrouped="True" SelectionMode="Single" SelectionChanged="OnSelectionChanged">
         <CollectionView.GroupHeaderTemplate>
             <DataTemplate>