Introduction
In this article we will see how we can group elements in ListBox.
Creating WPF Project
Fire up Visual Studio 2008 and create a new WPF Project. Name it as ListBoxSampleWPF.
Now we will add a ListBox to the application and it will look as following:
Now let's add some sample data to the ListBox.
public class Person
{
public string Name { get; set; }
public int Age { get; set; }
public string Country
{ get; set; }
}
ObservableCollection<Person>
myList;
public Window1()
{
InitializeComponent();
myList = new ObservableCollection<Person>()
{
new Person{ Name="Name 1", Age=24, Country="Japan"},
new Person{ Name="Name 2", Age=24, Country="India"},
new Person{ Name="Name 3", Age=24, Country="China"},
new Person{ Name="Name 4", Age=24, Country="Japan"},
new Person{ Name="Name 5", Age=24, Country="India"},
new Person{ Name="Name
6", Age=24, Country="US"},
new Person{ Name="Name 7", Age=24, Country="US"},
new Person{ Name="Name 8", Age=24, Country="India"},
new Person{ Name="Name 9", Age=24, Country="India"},
new Person{ Name="Name 10", Age=24, Country="India"},
new Person{ Name="Name 11", Age=24, Country="India"},
new Person{ Name="Name 12", Age=24, Country="China"},
new Person{ Name="Name 13", Age=24, Country="India"},
new Person{ Name="Name 14", Age=24, Country="India"},
new Person{ Name="Name 15", Age=24, Country="India"},
new Person{ Name="Name 16", Age=24, Country="China"},
new Person{ Name="Name 17", Age=24, Country="India"},
new Person{ Name="Name 18", Age=24, Country="India"},
new Person{ Name="Name 19", Age=24, Country="India"},
new Person{ Name="Name 20", Age=24, Country="US"},
new Person{ Name="Name 21", Age=24, Country="US"},
new Person{ Name="Name 22", Age=24, Country="India"},
};
lbPersonList.ItemsSource = myList;
}
Now run the application and we can see the list of persons in the ListBox.
Now we would like to see the persons from different countries. Then add the following code.
ICollectionView view = CollectionViewSource.GetDefaultView(myList);
view.GroupDescriptions.Add(new PropertyGroupDescription("Country"));
view.SortDescriptions.Add(new SortDescription("Country",
ListSortDirection.Ascending));
lbPersonList.ItemsSource = view;
And in XAML we need to add the GroupStyle for the ListBox.
<ListBox x:Name="lbPersonList" Margin="19,17,162,25" AlternationCount="2">
<ListBox.GroupStyle>
<GroupStyle
/>
</ListBox.GroupStyle>
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Now run the application and see the Grouped List.
One thing you must have noticed is that, The groups are sorted but the content of the group are not sorted.
It's a matter of writing a line of code and that is add another SortDescription.
ICollectionView view = CollectionViewSource.GetDefaultView(myList);
view.GroupDescriptions.Add(new PropertyGroupDescription("Country"));
view.SortDescriptions.Add(new SortDescription("Country", ListSortDirection.Ascending));
view.SortDescriptions.Add(new SortDescription("Name", ListSortDirection.Ascending));
lbPersonList.ItemsSource = view;
Now run the application and you will see the sorting in the grouped contents too.
Hope you like this article.