GridView's ItemContainerStyle and selection states
- by Roberto Casadei
I'm trying to change the appearance of gridview items when they are selected.
(Before, I used a trick with an IsSelected property in the ViewModel object bound to the containing grid and a bool-to-color converter, but I recognize that it is bad)
To do so, I do:
<GridView ItemContainerStyle="{StaticResource GridViewItemContainerStyle}" ...> ...
and
<Style x:Key="GridViewItemContainerStyle" TargetType="GridViewItem">
<Setter Property="Background" Value="Red" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="GridViewItem">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(Grid.Background)" Storyboard.TargetName="itemGrid">
<DiscreteObjectKeyFrame KeyTime="0" Value="Black"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="SelectionStates">
<VisualState x:Name="UnselectedSwiping"/>
<VisualState x:Name="UnselectedPointerOver"/>
<VisualState x:Name="Selecting"/>
<VisualState x:Name="Selected">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(Grid.Background)" Storyboard.TargetName="itemGrid">
<DiscreteObjectKeyFrame KeyTime="0" Value="White"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedSwiping"/>
<VisualState x:Name="Unselecting"/>
<VisualState x:Name="Unselected"/>
<VisualState x:Name="SelectedUnfocused"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid ... x:Name="itemGrid">
<!-- HERE MY DATA TEMPLATE -->
</Grid>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
When I run the app, the items are Black (as in the "normal" state). But selecting them does not turn them into White. Where am I wrong?
Moreover, it there a way to set "ItemContainerStyle" without having it to "overwrite" the "ItemTemplate" ???
