Per-Pixel Scrolling

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To enable per-pixel scrolling, use the property corresponding to the current view:

perpixelscrollingperpixelscrolling

To provide visual effect, set the TableView.AllowScrollAnimation property to true. The TableView.ScrollAnimationMode and TableView.ScrollAnimationDuration properties allow you to customize the animation. The first property specifies the scrolling mode, the second property specifies the animation length. The following modes are available:

NOTE

If per-pixel scrolling is enabled and rows have different heights, the last (bottom) visible row may not be displayed entirely. Because of the UI virtualization, the GridControl does not know the total viewport height in advance, and the scrolling speed differs depending on which rows are currently visible.

Example: How to Implement Custom Scroll Animation for Per-Pixel Scrolling

This example shows how to handle the CustomScrollAnimation event to implement custom animation played when grid data is vertically scrolled (per-pixel scrolling). Note the view's AllowPerPixelScrolling and AllowScrollAnimation options must be enabled.

Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Data
Imports System.Windows.Documents
Imports System.Windows.Input
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Windows.Navigation
Imports System.Windows.Shapes
Imports System.Windows.Media.Animation

Namespace DXGrid_CustomScrollAnimation
    ''' <summary>
    ''' Interaction logic for MainWindow.xaml
    ''' </summary>
    Partial Public Class MainWindow
        Inherits Window

        Public Sub New()
            InitializeComponent()
            grid.ItemsSource = GetData()
        End Sub

        Private Sub tableView1_CustomScrollAnimation(ByVal sender As Object, ByVal e As DevExpress.Xpf.Grid.CustomScrollAnimationEventArgs)
            e.Storyboard = New Storyboard()
            Dim animation As New DoubleAnimation()
            animation.From = e.OldOffset
            animation.To = e.NewOffset
            animation.Duration = New Duration(TimeSpan.FromMilliseconds(600))
            animation.EasingFunction = New ExponentialEase() With {.Exponent = 0}
            e.Storyboard.Children.Add(animation)
        End Sub

        Private Function GetData() As List(Of TestDataObject)
            Dim _list As New List(Of TestDataObject)()
            For i As Integer = 0 To 99
                _list.Add(New TestDataObject() With {.ID = i, .Value = String.Format("Value {0}", i)})
            Next i
            Return _list
        End Function
    End Class

    Public Class TestDataObject
        Public Property ID() As Integer
        Public Property Value() As String
    End Class
End Namespace