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ListViewExtensions

The ListViewExtensions class provide a lightweight way to extend every control that inherits the ListViewBase class with attached properties. This means that all the extensions in this class can apply to both ListView, GridView and other controls.

Platform APIs: ListViewExtensions, ItemContainerStretchDirection

ListViewBase Extensions

AlternateColor

The AlternateColor property provides a way to assign a background color to every other item.

Warning

The ContainerContentChanging event used for this extension to work, will not be raised when the ItemsPanel is replaced with another type of panel than ItemsStackPanel or ItemsWrapGrid.

Here is how this property can be used in XAML:

<Page ...
     xmlns:ui="using:Microsoft.Toolkit.Uwp.UI">

<ListView
    ui:ListViewExtensions.AlternateColor="Silver"
    ItemsSource="{x:Bind MainViewModel.Items, Mode=OneWay}" />

AlternateItemTemplate

The AlternateItemTemplate property provides a way to assign an alternate DataTemplate to every other item. It is also possible to combine with the AlternateColor property.

Warning

The ContainerContentChanging event used for this extension to work, will not be raised when the ItemsPanel is replaced with another type of panel than ItemsStackPanel or ItemsWrapGrid.

Here is how this property can be used in XAML:

<Page ...
     xmlns:ui="using:Microsoft.Toolkit.Uwp.UI">

<Page.Resources>
    <DataTemplate x:Name="NormalTemplate">
        <TextBlock Text="{Binding}" Foreground="Green"></TextBlock>
    </DataTemplate>
    
    <DataTemplate x:Name="AlternateTemplate">
        <TextBlock Text="{Binding}" Foreground="Orange"></TextBlock>
    </DataTemplate>
</Page.Resources>

<ListView
    ItemTemplate="{StaticResource NormalTemplate}"
    ui:ListViewExtensions.AlternateItemTemplate="{StaticResource AlternateTemplate}"
    ItemsSource="{x:Bind MainViewModel.Items, Mode=OneWay}" />

Command

ListViewExtensions provides extension method that allow attaching an ICommand to handle ListViewBase item interaction by means of ItemClick event.

Important

ListViewBase IsItemClickEnabled must be set to true.

Here is how this property can be used in XAML:

<Page ...
     xmlns:ui="using:Microsoft.Toolkit.Uwp.UI">
     
<ListView
    ui:ListViewExtensions.Command="{x:Bind MainViewModel.ItemSelectedCommand, Mode=OneWay}"
    IsItemClickEnabled="True"
    ItemsSource="{x:Bind MainViewModel.Items, Mode=OneWay}"
    SelectionMode="None" />

StretchItemContainerDirection

The ItemContainerStretchDirection property provides a way to stretch the ItemContainer in horizontal, vertical or both ways. The allowed values are items from the ItemContainerStretchDirection type.

Warning

The ContainerContentChanging event used for this extension to work, will not be raised when the ItemsPanel is replaced with another type of panel than ItemsStackPanel or ItemsWrapGrid.

Here is how this property can be used from XAML:

<Page ...
     xmlns:ui="using:Microsoft.Toolkit.Uwp.UI">

<ListView
    ui:ListViewExtensions.StretchItemContainerDirection="Horizontal"
    ItemsSource="{x:Bind MainViewModel.Items, Mode=OneWay}" />

SmoothScrollIntoView

Use SmoothScrollIntoView helps to scroll the item into the view with animation. Specify the ItemPosition property to align the item.

Syntax

// Scrolling with index
await MyGridView.SmoothScrollIntoViewWithIndexAsync(index: int, itemPlacement: ItemPlacement, disableAnimation: bool, scrollIfVisibile: bool, additionalHorizontalOffset: int, additionalVerticalOffset: int);

// Scrolling with item
await MyGridView.SmoothScrollIntoViewWithItemAsync(item: object, itemPlacement: ItemPlacement, disableAnimation: bool, scrollIfVisibile: bool, additionalHorizontalOffset: int, additionalVerticalOffset: int);
' Scrolling with index
Await MyGridView.SmoothScrollIntoViewWithItemAsync(index:=Integer, itemPlacement:=ItemPlacement.Bottom, disableAnimation:=Boolean, scrollIfVisibile:=Boolean, additionalHorizontalOffset:=Integer, additionalVerticalOffset:=Integer)

' Scrolling with item
Await MyGridView.SmoothScrollIntoViewWithItemAsync(item:=Object, itemPlacement:=ItemPlacement.Bottom, disableAnimation:=Boolean, scrollIfVisibile:=Boolean, additionalHorizontalOffset:=Integer, additionalVerticalOffset:=Integer)

Sample Output

SmoothScrollIntoView Helper

Methods

Methods Return Type Description
SmoothScrollIntoViewWithIndexAsync(int, ScrollItemPlacement, bool, bool, int, int) Task Smooth scroll item into view With index number
SmoothScrollIntoViewWithItemAsync(object, ScrollItemPlacement, bool, bool, int, int) Task Smooth scroll item into view With item object

Method params

Properties Type Description
intex int Intex of the item to be scrolled. Index can be negative
item int Intex of the item to be scrolled
itemPosition ScrollItemPlacement Specify the position of the Item after scrolling
disableAnimation bool To disable the scrolling animation
scrollIfVisibile bool Set true to scroll even if the scroll to item is visible so that the item will be aligned depend upon itemPosition
additionalHorizontalOffset bool Give addition horizontal offset
additionalVerticalOffset bool Give addition vertical offset

ItemPosition

ScrollItemPlacement Description
Default If visible then it will not scroll, if not then item will be aligned to the nearest edge
Left Aligned left
Top Aligned top
Center Aligned center
Right Aligned right
Bottom Aligned bottom

Examples

  • We can use this extension to make the selected item always centered.

    Sample Code

    <ListView ItemsSource="{x:Bind itemSources}" SelectionChanged="ListView_SelectionChanged">
        <ListView.ItemTemplate>
            <DataTemplate>
                <!-- Your Template -->
            </DataTemplate>
        </ListView.ItemTemplate>
        <ListView.ItemsPanel>
            <ItemsPanelTemplate>
                <StackPanel Orientation="Horizontal"/>
            </ItemsPanelTemplate>
        </ListView.ItemsPanel>
    </ListView>
    
    private async void ListView_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        var listView = (sender as ListView);
        await listView.SmoothScrollIntoViewWithIndexAsync(listView.SelectedIndex, ScrollItemPlacement.Center, false, true);
    }
    
    Private Async Sub ListView_SelectionChanged(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)
        Dim listView = (TryCast(sender, ListView))
        Await listView.SmoothScrollIntoViewWithIndexAsync(listView.SelectedIndex, ScrollItemPlacement.Center, False, True)
    End Sub
    

    Sample Output

    Use Case 1 Output

Requirements

Device family Universal, 10.0.16299.0 or higher
Namespace Microsoft.Toolkit.Uwp.UI.Extensions
NuGet package Microsoft.Toolkit.Uwp.UI

API