Sharing styles between several GridView controls - xaml

Question

I need to style several GridView throughout my application with the same visual styles. This style includes customizing the ItemsPanel property as well as the GroupStyle property.
My problem is that the GroupStyle property of GridView is not a dependency property. So the code I would have liked to write (see below) does not work.
Do you know a clean way to share a style (including GroupStyle) between several GridViews?
The only thing I can think of is using a GroupStyleSelector but it's kind of stupid since there is no selection to make: it's always the same GroupStyle that's being used. Moreover, I suspect it wouldn't be reflected at design time in VS & Blend.
The code I would love to use:
<GridView
ItemsSource="..."
ItemTemplate="..."
Style="{StaticResource MainMenuStyle}"/>
<Style TargetType="GridView" x:Key="MainMenuStyle">
<Setter Property="ItemsPanel">
<Setter.Value>
...
</Setter.Value>
</Setter>
<Setter Property="GroupStyle">
<Setter.Value>
<GroupStyle>
...
</GroupStyle>
</Setter.Value>
</Setter>
</Style>

Answer 1

I've got a magical happy solution.
You can create a custom Attached Property that you set in the Style, and upon setting it internally sets the GroupStyle property on the GridView.
Attached Property:
// Workaround for lack of generics in XAML
public class GroupStyleCollection : Collection<GroupStyle>
{
}
public class GroupStyleHelper
{
public static ICollection<GroupStyle> GetGroupStyle(ItemsControl obj)
{
return (ICollection<GroupStyle>)obj.GetValue(GroupStyleProperty);
}
public static void SetGroupStyle(ItemsControl obj, ICollection<GroupStyle> value)
{
obj.SetValue(GroupStyleProperty, value);
}
public static readonly DependencyProperty GroupStyleProperty =
DependencyProperty.RegisterAttached(
"GroupStyle",
typeof(ICollection<GroupStyle>),
typeof(GroupStyleHelper),
new PropertyMetadata(null, OnGroupStyleChanged));
private static void OnGroupStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ItemsControl itemsControl = d as ItemsControl;
if (itemsControl == null)
return;
RefreshGroupStyle(itemsControl, GetGroupStyle(itemsControl));
}
private static void RefreshGroupStyle(ItemsControl itemsControl, IEnumerable<GroupStyle> groupStyle)
{
itemsControl.GroupStyle.Clear();
if (groupStyle == null)
return;
foreach (var item in groupStyle)
{
itemsControl.GroupStyle.Add(item);
}
}
}
XAML Style:
<Style TargetType="ItemsControl">
<Setter Property="GroupStyleTest:GroupStyleHelper.GroupStyle">
<Setter.Value>
<GroupStyleTest:GroupStyleCollection>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<TextBlock FontWeight="Bold" FontSize="15" Text="{Binding Path=Name}" Foreground="HotPink"/>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</GroupStyleTest:GroupStyleCollection>
</Setter.Value>
</Setter>
</Style>
Disclaimer: I'm testing this in WPF rather than WinRT but it should work the same, as far as I can tell. That's also why I'm using an ItemsControl rather than GridView, but the property is ItemsControl.GroupStyle anyway.

Answer 2

I've a solution and that will definitely work as per your question, but though you should decide whether to use that in your case or not.
If you have to make same style of a control in all over the project, then you should make one common folder and in that folder
create one "Custom User Control" and apply all of your style and
customize it however you want.
After that when you need to apply that same kind of style on same control (any grid control) then simply add that customized user
control instead of predefined control
By doing this you'll also achieve MVC architecture and modularity.
I'm developing Windows 8 Metro app in C# with XAML, and in that whenever i wanted this approach then i always use this solution and it always works...
to create custom user control, you should use visual studio & in that right click on project -> add -> new item -> User Control
(Sorry if you couldn't find your solution here, but i think this might help...)