Implement RadGridView Endless Scrolling

Environment

Product	RadGridView for WPF
Version	2024.3.821

Description

How to implement endless/infinity scrolling in RadGridView, where new data items are added in the ItemsSource when the user scrolls to the bottom of the data view.

Solution

To do this, you can get the GridViewScrollViewer of RadGridView and subscribe to its ScrollChanged event. When the user reaches the ExtentHeight of the scroll viewer, add the new portion of items.

Implement infinity scrolling

public partial class MainWindow : Window 
{ 
    private ObservableCollection<RowInfo> allData = new ObservableCollection<RowInfo>(); 
    private ObservableCollection<RowInfo> source = new ObservableCollection<RowInfo>(); 
 
    public MainWindow() 
    { 
        StyleManager.ApplicationTheme = new FluentTheme(); 
        InitializeComponent(); 
 
        allData = new ObservableCollection<RowInfo>(); 
        for (int i = 0; i < 1000; i++) 
        { 
            allData.Add(new RowInfo() { Name = "Item " + i, Number = i }); 
        } 
 
        for (int i = 0; i < 50; i++) 
        { 
            source.Add(allData[i]); 
        }         
        this.gridView.ItemsSource = source;             
    } 
 
    private void gridView_Loaded(object sender, RoutedEventArgs e) 
    { 
        var scrollViewer = this.gridView.FindChildByType<GridViewScrollViewer>(); 
        scrollViewer.ScrollChanged += ScrollViewer_ScrollChanged; 
    } 
 
    private void ScrollViewer_ScrollChanged(object sender, System.Windows.Controls.ScrollChangedEventArgs e) 
    { 
        if ((e.VerticalOffset + e.ViewportHeight) == e.ExtentHeight) 
        { 
            var startIndex = source.Count - 1; 
            var loadSize = 10; 
 
            var itemsToLoad = allData.Skip(startIndex).Take(loadSize); 
            foreach (var item in itemsToLoad) 
            { 
                source.Add(item); 
            } 
        } 
    } 
}