2,008 bytes added,
14:16, 18 May 2017 A collection of property-based content sorting criteria can be applied to child object lists. {{Version/WinXSince|2.6.1}} Some common use cases are as follows.
* A user can click on a header to sort a child list based on a certain property's value;
* A customizer can create UI that presents such headers, each applying to a different property.
For example. One can customize the ChildArea template to include the following.
<source lang = "xml">
<Grid>
<Grid.Resources>
<converters:SortDirectionToSymbolConverter x:Key="SDToSymbolConverter" />
</Grid.Resources>
<Border Background="#8000488E" Visibility="{Binding Children.Sorting[SomePropertyName], Converter={StaticResource NullObjOrEmptyStrColConverter}}" />
<Border Background="#90707070" Visibility="{Binding Children.Sorting[SomePropertyName], Converter={StaticResource NullObjOrEmptyStrVisConverter}}" />
<Button FontFamily="Segoe MDL2 Assets"
Content="{Binding Children.Sorting[SomePropertyName], Converter={StaticResource SDToSymbolConverter}}"
Command="{Binding Children.SortByPropertyCommand}" CommandParameter="SomePropertyName" />
</Grid>
</source>
This is shown as a single header/button. The Command binding ([[SortByPropertyCommand]]) allows the child list to be sorted (ascending on the first click, descending on the second) by property "SomePropertyName".
The binding on Content ensures the header displays a proper visual symbol. The ascending/descending/unsorted symbols can also be customized like the following if necessary.
<source lang = "xml">
<converters:SortDirectionToSymbolConverter x:Key="SDToSymbolConverter" Unsorted="◊" Ascending="△" Descending="▽" />
</source>
The codes for different "Segoe MDL2 Assets" symbols can be found [[https://docs.microsoft.com/en-us/windows/uwp/style/segoe-ui-symbol-font|here]].
{{Hint|The Borders in the example are not mandatory. They merely highlight the currently active sorting header/button.}}